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Wong, Hoi-leong Xavier, and 王凱亮. "The functional crosstalk between MT1-MMP and ADAMs in craniofacial & vascular development." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/197072.
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Larsson, Emanuel. "Quantitative Analysis of Bone Tissue Engineering Scaffolds and Skull Bones by means of Synchrotron and Conventional X-ray Computed Microtomography." Thesis, Linköpings universitet, Teknisk biologi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-63196.
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The study of internal structure of materials has always been an essential issue in a variety of application fields, from the medical radiology to the materials science. X-ray computed microtomography (with both conventional and synchrotron radiation sources) has a great potential for these purposes because its three-dimensional and non destructive nature as well as the fact that it does not require any sample preparation and it allows to study samples under stress or after consecutive treatments. The recent developments of new X-ray sources with innovative imaging techniques, as well as novel high resolution detectors, allow moving forward the maximum achievable resolution of this technique to a few micrometers or even less. This contributed to increase its application in biomedical purposes, but also to raise the need for quantitative analysis of the reconstructed data. Indeed in most of the cases a quantitative characterization of the samples microstructures is needed to better understand their physical and chemical behavior, the effects of manufacturing process or the response to stress. Dedicated software packages have been developed to perform a geometrical and morphological characterization of the samples texture and to evaluate some typical parameters commonly used to classify porous media such as porosity, cell size distribution, connectivity and anisotropy. In this work two case studies have been considered for the application of a quantitative analysis approach to microtomography datasets: the first concerns the characterization of bone ingrowth within tissue engineering scaffolds, while the second is related to the extraction of morphological descriptors for the architecture of human skull bones. It will be shown how suitable image processing and analysis techniques are able to effectively quantify significant parameters such as the trabecular thickness of the skull bones as well as the porosity and the degree of connectivity of bone tissue engineering scaffolds. Similar quantitative analysis methods applied to microtomography images have to be considered as an effective methodology for a comprehensive characterization of other biomedical samples.
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Eley, Karen A. "Imaging the craniofacial skeleton : is MRI a viable alternative to ionising radiation?" Thesis, University of Oxford, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.711645.
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Cooter, Rodney D. "Craniofacial fracture patterns : a thesis submitted for the degree of Doctor of Medicine /." Title page, contents and abstract only, 1990. http://web4.library.adelaide.edu.au/theses/09MD/09mdc779.pdf.
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Chance, Charles Allen. "Dependence of craniofacial growth on stages of cervical vertebral maturation and stages of mandibular canine mineralization." View the abstract Download the full-text PDF version, 2006. http://etd.utmem.edu/ABSTRACTS/2006-005-chance-index.htm.
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Thesis (M.S.)--University of Tennessee Health Science Center, 2006.<br>Title from title page screen (viewed on October 8, 2007 ). Research advisor: Edward Harris, Ph.D. Document formatted into pages (xiii, 156 p. : ill.) Vita. Abstract. Includes bibliographical references (p. 137-147).
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Yilmaz, Yasemin. "Les pratiques funéraires des populations néolithiques d’Anatolie : le cas de Cayönü." Thesis, Bordeaux 1, 2010. http://www.theses.fr/2010BOR14013/document.
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Cette étude porte sur le «Skull Building» de Çayönü (Sud-Est anatolien, Néolithiqueprécéramique), qui est l’un des plus anciens bâtiments à usage funéraire au Proche-Orient. Les restes humains provenant des différents dépôts osseux (110.460fragments) du «Skull Building» ont été étudiés au travers d’une approche archéoantropologiqueet taphonomique qui n’avait encore jamais été appliquée à un sitepréhistorique anatolien. Nous avons mis au point un logiciel de dénombrement,estimé le nombre minimum d’individus inhumés lors de chacune des deux phasesd’utilisation (NMI = 97 pour le bâtiment ovalaire, NMI = 231 pour le bâtimentrectangulaire) et mis en évidence un changement des pratiques entre le bâtimentovalaire (le plus ancien) et le bâtiment rectangulaire (le plus récent). Les résultatsobtenus permettent de proposer une nouvelle interprétation du fonctionnement de cebâtiment, dans la mesure où les analyses ont montré que les différents dépôts de laseconde phase d’utilisation (bâtiment rectangulaire) étaient liés entre eux<br>This study focuses on the "Skull Building" of Çayönü (Southeast Anatolian PrepotteryNeolithic), which is one of the oldest buildings for burial use in the MiddleEast. Human remains from different bone deposits (110,460 fragments) of the "SkullBuilding" have been studied through an archaeo-anthropological and taphonomicapproach which had never been applied to a prehistoric site in Anatolia. We havedeveloped a software for counting, estimated the minimum number of individualsburied in each of the two phases of use (NMI = 97 for the Oval Building, NMI = 231for the Rectangular Building) and highlighted a change in practices between the ovalbuilding (the oldest) and the rectangular building (most recent). The results obtainedallow proposing a new interpretation for the functions of this building, insofar as theanalysis showed that different deposits of the second phase of use (RectangularBuilding) were interrelated
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Kostíková, Martina. "Návrh testovací figuríny pro nárazové zkoušky." Master's thesis, Vysoké učení technické v Brně. Ústav soudního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-318116.
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The main objective of this thesis is construction of crash test dummy for vehicle-pedestrian crash tests. There is review of nowadays used crash test dummies types in the introduction of this thesis. This is followed by part describing construction itself. Chapter about construction begins by characterizing of used materials features in relation with real human body physiology. Main part of chapter is describing construction of crash test dummy’s skeleton and its individual components including 3D modelling and strength analysis. Thesis is finished by cost assessment.
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Yo, Done Sik. "Imaging and segmentation of bone in neurological magnetic resonance." Thesis, University College London (University of London), 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267575.
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Andersson, Frida. "Finite Element Modeling of Skull Fractures : Material model improvements of the skull bone in theKTH FE head model." Thesis, KTH, Skolan för teknik och hälsa (STH), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-192629.
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The main aim of this project was to develop a model for predicting skull fractures of a 50th percentile male, using a finite element head model developed at the Neuronics department of KTH, Royal Instituteof Technology. The skull bone is modeled as a three layered bone, where the outer and inner tables are modeled as shell elements, while the diploë is modeled by two layers of solid elements. The material model of the tables was changed from the material model MAT_PLASTIC_KINEMATIC to a material model including a damage parameter to soften the damaged material and to enable ploting of the damage of the skull bone. Due to the coarse mesh of the FE head model the material model was not allowed to include any erosion, deleting element as they reach their ultimate strain. With these requests, two materials from the LS-DYNA material library seemed appropriate: material 81,MAT_PLASTICITY_WITH_DAMAGE and material 105, MAT_DAMAGE_2. To evaluate these materials and adjust the input parameters a dog bone FE model was developed and tension tests were simulated with this model, equivalent to tension tests performed on equally shaped skull bone specimens. The material simulating a behavior most similar to the behavior from the tension tests turned out to be material 81. This material model was then implemented in the full FE head model for further input parameter adjustment and validation. Four different cadaver experiments were simulated, with different impacting objects: sphere, box, cylinder and flat cylinder surface, and impacted areas of the head: vertex, temporo-parietal and frontal. The forces obtained in the simulations were compared to the forces of the cadaver experiments. The fracture prediction was based on the damage parameter, which could be plotted to visualize the areas where the ultimate strain was exceeded and thereby the area most likely to be fractured. This parameter was then compared to the documented fractures from the cadaver experiments. The result showed that using material 81 with the input parameter EPPFR=0.05 gave the overall most accurate forces and fracture predictions. The breaking stress, σB, did not affect the fractures significantly but a reduced σB resulted in reduction of the peak forces. The thickness of the diploë did not have any significant impact on the fracture occurrence, but a thinner diploë had a reducing impact on the peak forces as well.
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Karamini, Christina Cooper Lyndon F. "Biopolymer matrix enhances bone regeneration in rat critical size skull defects." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2006. http://dc.lib.unc.edu/u?/etd,538.
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Thesis (M.S.)--University of North Carolina at Chapel Hill, 2006.<br>Title from electronic title page (viewed Oct. 10, 2007). "... in partial fulfillment of the requirements for the degree of Master of Science in the Department of Prosthodontics (School of Dentistry)." Discipline: Prosthodontics; Department/School: Dentistry.
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Ferguson, James. "THE SPATIAL AND TEMPORAL ROLE OF EZH2 IN SKULL BONE FORMATION." Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case1530898825341447.
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Umeda, Hiroo. "In situ Tissue Engineering of Canine Skull with Guided Bone Regeneration." Kyoto University, 2009. http://hdl.handle.net/2433/124318.
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Yamada, Keisuke. "Potentiality of bFGF incorporated in biodegradable hydrogels for skull bone regeneration." Kyoto University, 1997. http://hdl.handle.net/2433/202203.
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Engelke, Katharina. "Intravital Multiphoton Microscopy Analysis of Spatial Relationships in Murine Skull Bone Marrow." Diss., lmu, 2009. http://nbn-resolving.de/urn:nbn:de:bvb:19-105870.
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Zhu, Zimo. "Techniques for Finite Element Modeling and Remodeling of Bones with Applications to Pig Skulls." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1512045879980572.
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Martins, Angélica Cristina de Oliveira. "Avaliação histomorfométrica comparativa do processo de reparo de defeitos ósseos perenes em calvária de ratos tratados com -fosfato tricálcio, hidroxiapatita sintética, hidroxiapatita sintética + -fosfato tricálcio e osso autógeno." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/25/25142/tde-17082010-153553/.
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Os objetivos do trabalho foram caracterizar as biocerâmicas a base de hidroxiapatita (HA), -fosfato tricálcio (TCP) e o compósito HA/TCP na proporção 60:40 pela análise microestrutural e por Espectrometria de Energia Dispersiva de Raios-X (EDS) ao microscópio eletrônico de varredura, e comparar histomorfometricamente o processo de reparo ósseo de defeitos cranianos perenes tratados com essas três diferentes cerâmicas e o enxerto autógeno nos períodos de 0, 30, 90 e 180 dias pós-operatório. Microestruturalmente, a HA apresentou superfície irregular com concavidades, fendas e grande quantidade de microporos; o TCP exibiu superfície irregular e baixa resistência mecânica; a HA/TCP apresentou superfície lisa com raras concavidades e ausência de porosidades. As cerâmicas estavam constituídas pelos elementos O, P e Ca, sendo que a relação Ca/P seguiu a ordem: HA/TCP > HA > TCP. Morfometricamente, o volume inicial enxertado foi aproximadamente de 60 mm3 para todos os tratamentos. Entre 30 e 180 dias, o volume total da região do enxerto (Vtre) e do material enxertado (VM) manteve-se constante nos defeitos tratados com osso autógeno (Vtre = 53,61 mm³, VM =20,11 mm³), HA (Vtre = 60,13mm³, VM = 32,72 mm³), HA/TCP (Vtre = 57,60mm³, VM = 31,61 mm³), TCP (Vtre = 38,27mm3, VM = 10,07 mm³). Aos 30 dias, o volume de tecido ósseo no grupo autógeno foi de 22,06 mm³, ocupando quase a totalidade dos espaços entre as partículas, enquanto que, nos grupos HA e HA/TCP foi de apenas 7,62 mm³, sendo parte dos espaços (19,10 mm3), constituído por tecido conjuntivo fibroso. Entre 30 e 180 dias, o volume de tecido ósseo não apresentou diferenças estatísticas significantes (p>0,05). O número absoluto de osteoblastos e osteócitos no grupo autógeno foi, respectivamente, de 118,57 x102 e 178,57 x102 células, aos 30 dias, diminuindo 40,16% e 29,09% aos 90 dias, decorrente do processo de remodelação óssea. Nos grupos HA e HA/TCP, o número absoluto de osteoblastos e osteócitos foram similares e permaneceram constantes dos 30 aos 180 dias, com uma média de 39,13 x102 e 132,20 x102 células, respectivamente. Com relação ao grupo TCP, o volume de tecido ósseo foi de 4,16mm3 aos 30 dias e aumentou 70,27% aos 90 dias, passando a ocupar 13,93 mm³ do Vtre. Concomitantemente, o número absoluto de osteoblastos e osteócitos passaram, respectivamente, de 5,64 x102 e 37,01 x102 células, aos 30 dias, para 67,46 x102 e 166,13 x102 células, aos 90 dias. Baseados nos resultados aqui obtidos, concluímos que, no modelo experimental de defeitos cranianos em ratos, o enxerto autógeno é ainda, o padrão ouro para reconstrução óssea, enquanto que, dentre as cerâmicas analisadas, o TCP é o melhor biomaterial ósseo-substituto.<br>The aim of the work was to characterize the ceramics: hydroxyapatite (HA), -tricalcium phosphate (TCP) and the composite HA/TCP (60:40) through scaning electron microscope - energy dispersive system (SEM-EDS) analysis and to compare histomorphometrically the repair of perennial skull defects treated with these three different ceramics and autogenous graft at 0, 30, 90 and 180 days post-operatively. Microstructurally, HA showed irregular surface with concavities, cracks and several pores. TCP also presented irregular surface and low mechanical strength. HA/TCP showed smooth surface with rare concavities and pores. The ceramics were constituted by the elements O, P and Ca, and the relation Ca/P follow the order: HA/TCP > HA > TCP. Morphometrically, the initial graft volume was approximately 60 mm3 for all treatments. Between 30 and 180 days, the total volume of the grafted area (Vtga) and of the implanted material (Vim) were constant in the following groups: autogenous (Vtga = 53,61 mm³; Vim = 20,11 mm3), HA (Vtga = 60,13mm³; Vim = 32,72 mm3), HA/TCP (Vtga = 57,60mm³; Vim = 31,61 mm3) and TCP (Vtga = 38,27mm³; Vim = 10,07 mm3). At 30 days, the bone tissue volume was of 22,06 mm3 in the autogenous group, occupying totally the space among the particles, while in the HA and HA/TCP groups was only 7,62 mm3. At 30 and 180 days, the bone tissue volume did not show statistical differences (p>0.05). The total number of osteoblasts and osteocytes in the autogenous group was respectively, 118, 57 x 102 and 178,57 x 102 cells, at 30 days, reducing 40,16% e 29,09%, at 90 days, due to bone remodeling. In the HA and HA/TCP groups, a similar and stable number of osteoblasts and osteocytes were observed during all periods, with mean of 39,13 x 102 and 132,20 x 102 cells, respectively. In the TCP group, the bony tissue volume was of 4,16 mm3, at 30 days, increasing 70,27% at 90 days. Concomitantly, the total number of osteoblasts and osteocytes was respectively, 5,64 x 102 and 37,01 x 102 cells, at 30 days, achieving 67,46 x 102 and 166,13 x 102 cells, at 90 days. Based in the results obtained here, we concluded that in the rat skull defect model the autogenous bone is yet the good standard graft material for bone reconstruction and that among the tested ceramics, the TCP is the best bone graft substitute.
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Fraser, Sheena Mary. "Mammals in Late Neolithic Orkney (with reference to mammal bone recovered from Links of Noltland, Westray)." Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/26007.
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Excavation of thirty skulls, twenty-eight cattle and two sheep from the foundation course of a Late Neolithic structure at Links of Noltland (LON), Structure 9, is the starting point for this thesis, which investigates the economic and socio-cultural relationships of cattle and other mammals on Orkney communities between 3000 and 2500 BC. The LON settlement was located on a machair plain in Westray, the most N-W island within the Orkney archipelago (HY 428 493). Male and female cattle skulls were inter-mixed within the LON foundation course so a “bull cult” is not represented. The sequence from living skulls to skulls “animating the building is (i) breed/acquire (ii) nurture (iii) cull/butcher (iv) consume (v) transform to object (vi) curate (vii) deposit. A skull deposit infilling an internal passageway from another LON, Structure 18, is compared and contrasted with the Structure 9 foundation deposit. Special treatment of cattle skulls from a wide range of European and Near-East sites is also reviewed to emphasise the widespread use of this symbol during the Neolithic period. Orkney was separated from mainland Scotland prior to the establishment of the LON settlement so consideration is given to modes of arrival for mammals and their impact on this depauperate archipelago. Cattle and sheep dominated the domestic mammal remains examined, pig and dog were rare and goat and horse absent. The most abundant non-domestic mammals were red deer and Orkney voles, but otters and sea mammals were also present in low numbers. Genetic studies indicate that one cattle skull carried genetic material from aurochs, wild cattle. To date there is sparse evidence of interbreeding between wild aurochs and Neolithic domesticated cattle in Europe and none in Britain. The alterative explanation that aurochs were already present on Orkney during the Neolithic is explored. Articulated red deer deposits from LON were also examined. Although previous publications explored the possibility that these deposits are “ritual” other possible explanations for these deposits are outlined. No parallels were noted between the cattle skull and articulated red deer deposits, but the importance of antler for practical and symbolic use in Neolithic Orkney may be under-estimated. Stature of cattle remained relatively stable during the Mid to Late Neolithic in Orkney but underwent diminution by the Iron Age. A similar, but less marked reduction was also noted for sheep, but red deer already had small stature compared with early Holocene mainland Scotland red deer. The thesis concludes that cattle, sheep and red deer were of fundamental importance to the Neolithic society of Orkney, providing surplus food, tools and possibly traction, to support an increasingly sophisticated Neolithic society undertaking construction of complex structures and monuments. In addition, cattle fulfilled an important role in their cultural and spiritual life.
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Hong, Liu. "Bone regeneration at rabbit skull defects by TGF-β1 incorporated in hydrogels with different biodegradabilities". Kyoto University, 2000. http://hdl.handle.net/2433/180823.
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Silva, Eduardo de Paula e. "Avaliação da administração intermitente de hormonio paratireoideo no reparo de defeitos na calvaria de ratos." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/290047.
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Orientadores: Silvana Pereira Barros, Darcy de Oliveira Tosello<br>Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba<br>Made available in DSpace on 2018-08-06T12:25:34Z (GMT). No. of bitstreams: 1
Silva_EduardodePaulae_M.pdf: 780892 bytes, checksum: 36e3cb799e53830c091d9721116dc937 (MD5)
Previous issue date: 2006<br>Resumo: O hormônio paratireóideo (PTH), quando administrado de maneira intermitente, promove anabolismo ósseo. Modelos experimentais em ratos, utilizando PTH intermitente, demonstraram que o anabolismo ósseo promovido diminui a perda óssea ocasionada por periodontite induzida, e acelera o reparo ósseo ao redor de implantes osseointegrados. Neste trabalho, nosso objetivo foi analisar a reparação óssea de defeitos em calotas cranianas de ratos que receberam PTH de maneira intermitente. Nas calotas cranianas de 32 ratos Wistar foram feitos defeitos de 4 mm de diâmetro. Após a cirurgia, 16 ratos receberam 40µg/kg de PTH três vezes por semana, enquanto 16 ratos (controle) receberam 40µg/kg do veículo do PTH com a mesma freqüência. Os animais foram sacrificados após 4 semanas e suas calotas foram removidas, radiografadas e processadas para análise histomorfométrica. As radiografias foram analisadas por meio de um fotodensitômetro, e os valores obtidos, tanto na morfometria quanto da densidade radiográfica, foram submetidos a teste estatístico (teste t). Os resultados mostraram que no grupo tratado com PTH, o tamanho do defeito residual foi menor ( 1,5 mm± 0,73) em relação ao grupo controle (1,98 mm ± 0,68) (p<0,05), e também que o grupo tratado apresentou uma maior densidade radiográfica do que o controle (p<0,01). A administração intermitente de PTH acelerou o processo de reparação dos defeitos na calota craniana<br>Abstract: The study aimed to investigate the effects ofintermittent parathyroid hormone PTH(1-34) treatment on bone regeneration of critically sized rat calvarial bone defects. A fullthickness bone defect (diameter 4 mm) was trephined in the central part of the parietal bones in ten-week old male Wistar rats. The animaIs were then divided into 2 groups of 16. The PTH group was subcutaneously administered with 40 microg PTH(1-34) /kg 3 times a week and to the control group it was given the vehicle. The rats were sacrificed at 28 days post surgery, the parietal bones were extracted, X- rayed and samples were prepared to obtain decalcified histological sections. The results were evaluated radiodensitometrically and histomorphometrically. The histomorphometric analysis for residual bone defect, using an image analyzer software, showed the mean values of 1.5mm for PTH group and 1.98mm for control group; indicating statistical significant differences among groups p<0.05 (test t). The photodensitometer analysis demonstrated a lower bone density in the group that did not receive PTH treatment (p<0.01). The experiment demonstrated that intermittent PTH (1-34) treatment could acelerate healing of rat calvarial defects<br>Mestrado<br>Histologia e Embriologia<br>Mestre em Biologia Buco-Dental
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Porzel, Alec P. "A Biomechanical Study of Critical Size Cranial Defect Reconstruction Techniques Using Two Bone Substitutes." University of Akron / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=akron1208547531.
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Schäfer, Thomas [Verfasser], and Michael [Akademischer Betreuer] Klintschar. "Xanthochromia of the skull bone associated with HbA1c / Thomas Schäfer ; Akademischer Betreuer: Michael Klintschar ; Institut für Rechtsmedizin." Hannover : Bibliothek der Medizinischen Hochschule Hannover, 2018. http://d-nb.info/1173462570/34.
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Lambi, Alex G. "The Intricate Role of Connective Tissue Growth Factor (CTGF/CCN2) in Prenatal Osteogenesis: A Heretofore Oversimplified Dogma of the CCN Field." Diss., Temple University Libraries, 2015. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/233693.
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Cell Biology<br>Ph.D.<br>Connective tissue growth factor (CTGF/CCN2) is axiomatically necessary for proper skeletal development and function. We need not look further than the studies that have been done to date utilizing mice genetically engineered to lack CTGF production. These CTGF null or knockout (KO) mice fail to form a normal murine skeleton and instead yield one littered with bony dysmorphisms, including incompetent craniofacial development, kinked limb bones, and misshapen ribs that are not conducive to proper respiratory function. As a result, the global lack of CTGF is incompatible with postnatal life. A closer look at several sites demonstrated defects in physiologic processes necessary for bone formation - angiogenesis, chondrogenesis, and osteogenesis. Therefore, the dogma in the CCN protein field to date has been that systemic ablation of CTGF production in vivo results in global defects in bone development. We believe this dogma is an oversimplification of the role of CTGF on skeletal development. Our initial impetus leading us to this belief was the gross identification of the specific skeletal sites malformed in CTGF KO mice, in particular the bones of the limbs. While in the lower limb of CTGF KO mice the tibiae and fibulae are misshapen, the adjacent femora and digits are phenotypically normal. The same is true for the upper limb, in which the radii and ulnae are phenotypically abnormal while the humeri and digits are normal. Therefore, we believe that the role of CTGF in skeletogenesis is site-specific such that its loss affects local skeletal patterning and/or mechanobiological cues resulting in the unique phenotype seen in CTGF KO mice. The research of this dissertation constitutes a comprehensive skeletal analysis of CTGF KO mice and in so doing we determined the extent and location of skeletal abnormalities. We found skeletal site-specific changes in growth plate organization, bone microarchitecture and shape and gene expression levels in CTGF KO compared to wild-type (WT) mice. Growth plate malformations included reduced proliferation zone and increased hypertrophic zone lengths. Appendicular skeletal sites demonstrated decreased metaphyseal trabecular bone, while having increased mid-diaphyseal bone and osteogenic expression markers. Axial skeletal analysis showed decreased bone in caudal vertebral bodies, mandibles, and parietal bones in CTGF KO mice, with decreased expression of osteogenic markers. Analysis of skull phenotypes demonstrated global and regional differences in CTGF KO skull shape resulting from allometric (size-based) and non-allometric shape changes. Localized differences in skull morphology included increased skull width and decreased skull length. We further continued the skeletal characterization of CTGF KO bones with an analysis of bone cell ultrastructure and matrix composition. These studies demonstrated that, while CTGF is not necessary for complete morphologic maturation of bone cells, global ablation results in ultrastructural features not commonly seen in WT bones. Our findings include drastically dilated rough endoplasmic reticulum (RER) in osteoblasts of the tibial diaphyseal region, comprising the phenotypic kink in CTGF KO mice and ultrastructural dysmorphologies of CTGF KO osteoclasts including multi-layered, membranous inclusions, decreased vacuolization and ruffled border extents, and disproportionately large clear zones. Lastly, FT-IR analysis demonstrated heterogeneity in CTGF KO bone composition. The results of this dissertation have revealed a more complex role for CTGF in osteogenesis and have identified potential mechanisms and future research directions to fully understand this intricate story.<br>Temple University--Theses
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Linares, Oscar Alonso Cuadros. "Mandible and Skull Segmentation in Cone Bean Computed Tomography Data." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-24072018-165943/.
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Cone Beam Computed Tomography (CBCT) is a medical imaging technique routinely employed for diagnosis and treatment of patients with cranio-maxillo-facial defects. CBCT 3D reconstruction and segmentation of bones such as mandible or maxilla are essential procedures in orthodontic treatments. However, CBCT images present characteristics that are not desirable for processing, including low contrast, inhomogeneity, noise, and artifacts. Besides, values assigned to voxels are relative Hounsfield Units (HU), unlike traditional Computed Tomography (CT). Such drawbacks render CBCT segmentation a difficult and time-consuming task, usually performed manually with tools designed for medical image processing. We introduce two interactive two-stage methods for 3D segmentation of CBCT data: i) we first reduce the CBCT image resolution by grouping similar voxels into super-voxels defining a graph representation; ii) next, seeds placed by users guide graph clustering algorithms, splitting the bones into mandible and skull. We have evaluated our segmentation methods intensively by comparing the results against ground truth data of the mandible and the skull, in various scenarios. Results show that our methods produce accurate segmentation and are robust to changes in parameter settings. We also compared our approach with a similar segmentation strategy and we showed that it produces more accurate segmentation of the mandible and skull. In addition, we have evaluated our proposal with CT data of patients with deformed or missing bones. We obtained more accurate segmentation in all cases. As for the efficiency of our implementation, a segmentation of a typical CBCT image of the human head takes about five minutes. Finally, we carried out a usability test with orthodontists. Results have shown that our proposal not only produces accurate segmentation, as it also delivers an effortless and intuitive user interaction.<br>Tomografia Computadorizada de Feixe Cônico (TCFC) é uma modalidade para obtenção de imagens médicas 3D do crânio usada para diagnóstico e tratamento de pacientes com defeitos crânio-maxilo-faciais. A segmentação tridimensional de ossos como a mandíbula e a maxila são procedimentos essências em tratamentos ortodônticos. No entanto, a TCFC apresenta características não desejáveis para processamento digital como, por exemplo, baixo contraste, inomogeneidade, ruído e artefatos. Além disso, os valores atribuídos aos voxels são unidades de Hounsfield (HU) relativas, diferentemente da Tomografia Computadorizada (TC) tradicional. Esses inconvenientes tornam a segmentação de TCFC uma tarefa difícil e demorada, a qual é normalmente realizada por meio de ferramentas desenvolvidas para processamento digital de imagens médicas. Esta tese introduz dois métodos interativos para a segmentação 3D de TCFC, os quais são divididos em duas etapas: i) redução da resolução da TCFC por meio da agrupamento de voxels em super-voxels, seguida da criação de um grafo no qual os vértices são super-voxels; ii) posicionamento de sementes pelo usuário e segmentação por algoritmos de agrupamento em grafos, o que permite separar os ossos rotulados. Os métodos foram intensamente avaliados por meio da comparação dos resultados com padrão ouro da mandíbula e do crânio, considerando diversos cenários. Os resultados mostraram que os métodos não apenas produzem segmentações precisas, como também são robustos a mudanças nos parâmetros. Foi ainda realizada uma comparação com um trabalho relacionado, gerando melhores resultados tanto na segmentação da mandíbula quanto a do crânio. Além disso, foram avaliadas TCs de pacientes com ossos faltantes e quebrados. A segmentação de uma TCFC é realizada em cerca de 5 minutos. Por fim, foram realizados testes com usuarios ortodontistas. Os resultados mostraram que nossa proposta não apenas produz segmentações precisas, como também é de fácil interação.
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Jacob, Velander. "Microwave phantoms for Craniotomy and bone defect monitoring." Thesis, Uppsala universitet, Fasta tillståndets elektronik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-256273.
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To facilitate examination for osteogenesis and follow up after craniotomy similar head models called phantoms are made. The head phantom should emulate the tissues from a real head. This requires that the realistic head phantom have the same electrical properties as relative permittivity (dielectric constant) and conductivity. Both must be validated and matched for right frequency spectrum. Validation measurements are performed by a coaxial slim probe connected to an Agilent Technologies E8364B network analyzer. The range of frequency measured is from 1 to 50 GHz, but matching will only be processed for 1 to 10 GHz. The resonance frequency for the antenna or sensor, which later will be used, is 2.4 GHz. The end results of the head phantom consists of three different tissues or layers (skin, bone and brain). Cavities will be created in the bone and will act as different defects or stages of re-growing bone. Phantom cube is done for examining the influence of implant in bone. Insertions of cube samples are made to emulate intermediates between implant and bone. Keywords: agar, BMP, body morphogenetic protein, bone implant, brain phantom, craniosynostosis, craniotomy, cube phantom, phantom, re-growing bone, skin phantom, skull phantom, tissue.
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Ueda, Hiroki. "Use of collagen sponge incorporating transforming growth factor β1 to promote bone repair in skull defects in rabbits". Kyoto University, 2001. http://hdl.handle.net/2433/150189.
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Bighetti, Bruna Barros. "Avaliação do reparo de defeito ósseo em calvária de ratos diabéticos tratados com Matriz Óssea Desmineralizada." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/25/25149/tde-09122011-094237/.
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O objetivo deste trabalho foi avaliar as atividades osteoindutoras e osteocondutoras da matriz alogênica óssea desmineralizada (MAOD) frente à diabetes no reparo de defeito de tamanho crítico em calvárias de ratos diabéticos. Para isso, 100 ratos machos Wistar foram divididos em 2 grupos: no grupo diabético (DIAB, n=50) foi injetado 47 mg/Kg de massa corporal de estreptozotocina, enquanto que no grupo controle (CTL, n=50) foi injetado solução fisiológica a 0,9%. A MAOD foi obtida de 50 ratos, cujo fêmur e tíbia foram retirados, desmineralizados com HCl a 0,6M por 24 horas, particulados em 1-2mm³, neutralizados com soro fisiológico e armazenados em álcool. Após a anestesia, foram realizados defeitos ósseos de 8 mm nas calvárias dos animais, sendo os grupos CTL COAG (n=25) e DIAB COAG (n=25) preenchidos com coágulo e os grupos CTL MAOD (n=25) e DIAB MAOD (n=25) preenchidos com MAOD. Após os períodos de 0, 7, 14, 21 e 42 dias, as calvárias foram coletadas. A análise radiográfica mostrou que houve formação de ilhas radiodensas no interior dos defeitos nos grupos CTL e DIAB tratados com MAOD, enquanto que nos grupos tratados com coágulo houve formação de áreas mais radiodensas somente nas bordas do defeito, corroborando com os resultados morfológicos, que mostraram nos grupos tratados com coágulo que o reparo ósseo teve início nas bordas do defeito, enquanto que nos grupos tratados com MAOD, a neoformação óssea ocorreu também nas áreas de reabsorção nas partículas de MAOD. De acordo com os resultados morfométricos, o volume de tecido ósseo aumentou gradativamente em todos os grupos, porém, esse aumento foi maior nos grupos CTL em relação aos seus respectivos tratamentos nos grupos DIAB (CTL COAG > DIAB COAG e CTL MAOD > DIAB MAOD) e maior quando comparados os grupos tratados com MAOD versus os respectivos grupos tratados com COAG (CTL MAOD > CTL COAG e DIAB MAOD > DIAB COAG). Assim, ao término de 42 dias, o volume de tecido ósseo no grupo CTL MAOD foi em média 3,24 vezes maior em relação aos demais grupos, os grupos CTL COAG e DIAB MAOD não apresentaram diferenças significativas e o grupo DIAB MAOD foi 1,81 vezes maior em relação ao DIAB COAG. Com esses resultados, conclui-se que embora o quadro de diabetes tenha influenciado no atraso do reparo, ainda assim, pode-se afirmar que a MAOD contribuiu com a neoformação óssea e com o reparo do defeito na calvária de animais saudáveis e diabéticos, por terem sido preservadas as suas características osteoindutoras e osteocondutoras.<br>The aim of this work was to evaluate the osteoinductive and osteoconductive activities of demineralized allogeneic bone matrix (DABM) against diabetes in repairing critical size defects in diabetic rats skulls. Therefore, 100 male Wistar rats were shered into two groups: in the diabetic group (DIAB, n=50) was 47 mg/Kg of body weight streptozotocin, while in the control group (CTL, n=50) was injected saline 0.9%. The DABM was obteined using 50 rats which were removed their femur and tibia bones, demineralized in 0.6 N HCl during 24 hours, cut into 1-2mm³ pieces, neutralized in saline and stored in alcohol. After anesthesia, were made 8 mm bone defects on skulls of rats, being the CTL CLOT group (n=25) and DIAB CLOT group (n=25) filled with blood clot and the CTL DABM group (n=25) and DIAB DABM group (n=25) filled with DABM. After 0, 7, 14, 21 and 42 days, the skulls were collected. The radiographic analysis showed radiodense islets inside the defects filled with DABM in CTL and DIAB groups, while groups filled with blood clot showed radiodense areas near the defect border, which is in agreement to the morphologic results, that had showed the begining of bone healing was near the defects border in groups filled with blood clot, while groups filled with DABM showed new bone formation also in resorption DABM areas. According to morphometric results, the volume of bone tissue had increased in all groups, however, this increase was more accentuated in CTL groups when compared to DIAB groups with respected treatments (CTL CLOT > DIAB CLOT and CTL DABM > DIAB DABM) and bigger when groups treated with DABM are compared to respestive groups treated with CLOT (CTL DABM > CTL CLOT e DIAB DABM > DIAB CLOT). Thereby, at the end of 42 days, the CTL DABM bone tissue volume was 3.24 greater than the other groups, the CTL CLOT and DIAB DABM groups didnt show any significant differenceand the DIAB DABM was 1,81 greater than DIAB CLOT. From these results, the conclusion is that although diabetes had delayed the repair, nevertheless, DABM contributed to bone neoformation and to the defect repair in skulls of healthy and diabetic animals, due to the osteoinductive and osteoconductive qualities had been preserved.
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Nwotchouang, Blaise Simplice Talla. "SKULL-BASED MORPHOMETRICS AND BRAIN TISSUE DEFORMATION CHARACTERIZATION OF CHIARI MALFORMATION TYPE I." University of Akron / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=akron1595877233083287.
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Parikh, Anand. "LONG-TERM CRANIAL RECONSTRUCTIONS IN FULL THICKNESS DEFECTS USING CARBONATED CALCIUM PHOSPHATE CEMENT WITH TITANIUM MESH SCAFFOLD IN A SHEEP MODEL: BIOMECHANICAL ANALYSIS." Akron, OH : University of Akron, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=akron1164993505.
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Thesis (M.S.)--University of Akron, Dept. of Biomedical Engineering, 2006.<br>"December, 2006." Title from electronic thesis title page (viewed 06/27/2007) Co-Advisors, Glen O. Njus, Daniel B. Sheffer; Faculty Reader, Mary C. Verstraete; Department Chair, Daniel B. Sheffer; Dean of the College, George K. Haritos; Dean of the Graduate School, George R. Newkome. Includes bibliographical references.
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Carlman, Maria, and Carina Engqvist. "Hur skall patienter med metastaser till skelettet förhålla sig till fysisk aktivitet? : en litteraturstudie." Thesis, Högskolan Väst, Institutionen för omvårdnad, hälsa och kultur, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-5122.
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Background : Many cancer patients who get bone metastases live longer thanks to the successful research and development of medicines during recent years. Many studies show general health benefits from physical activity. For patients with bone metastases the possibility of physical activity perhaps should limit? Nurses at oncological units are often in lifelong contact with this group of patients. It´s therefore important to have knowledge about the bone metastases and how it influence the patient´s possibility of performing physical activity in order to support and encourage the patient to safely physical activity. Aim : To describe the patient´s possibility of physical activity with metastases to the bone. Method : A literature study. Results : The extension of the bone metastases shall be verified through X-ray. Based on the result estimation should be done regarding the risks for fractures. Few metastases allow the patient to perform more physical activity. No study showed that physical activity according to carefully elaborated exercise programmes will be of any risk for patients with bone metastases. Conclusions : The conclusion of this study was that research within nursing of the chosen problem is limited. The nurse is the one who often meets this group of patients in treatment and it is important that he/she has adequate knowledge about the individual patients’ possibilities to perform physical activity. Even if the result was not that big there is still a consensus among the articles included. Nevertheless this area seems to be fairly unexplored and more studies are needed to strengthen the evidence.
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Mackey, Allison Ruth. "Maturation of skull properties with implications for the fitting and verification of the soft band bone-anchored hearing system for infants and young children." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/44058.
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Soft band bone-anchored hearing systems (BAHS) are optimal for individuals with conductive or mixed hearing losses. Although it is understood that bone-conduction hearing is different between infants and adults, few studies have attempted to explain why these differences exist or how they affect the fitting of a soft band BAHS. The main objectives in this study were: (i) to better understand how properties of the developing skull contribute to the maturation of bone-conduction attenuation and sensitivity, and (ii) to determine how future BAHS fitting and verification protocols should be adjusted for infants and young children.
The transcranial attenuation of pure-tone bone-conduction stimuli was measured on infants and young children (age 1 month to 7 years) and adults using sound pressure in the ear canal when the transducer was placed on different positions across the skull. In addition, the mechanical impedance magnitude for the forehead and temporal bone was collected for contact forces of 2, 4, and 5.4 N using an impedance head, a BAHS transducer, and a specially-designed holding device. This study was the first to measure mechanical impedance of the skull, which is an essential component to bone-conduction hearing, on young children and infants.
Transcranial attenuation was greatest for young infants, and decreased throughout maturation. Attenuation was also greater from the forehead compared to the contralateral temporal bone for infants and children over 10 months of age. In addition, mechanical impedance was lowest for the youngest infants and increased throughout maturation for low frequencies, but for high frequencies, these infants had the highest impedance on the temporal bone only. The effect of contact force was significant for low frequencies, and the effect of placement was significant for high frequencies. These results suggest that the properties of the developing skull relate to infant-adult differences in transcranial attenuation, and the mechanical impedance of the skin and subcutaneous tissue may explain the infant-adult differences in bone-conduction sensitivity. The results also provide important implications for fitting and verifying output from the BAHS for infants and young children.
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Fogaça, Walfredo Cherubini. "Análise da integração do aloenxerto ósseo de crânio criopreservado e irradiado, adicionado de medula óssea autógena: estudo experimental em coelhos." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/5/5158/tde-21082007-115356/.
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Buscando alternativas ao enxerto ósseo autógeno para reconstruções craniofaciais, propõe-se a utilização de aloenxerto ósseo de crânio criopreservado, irradiado e enriquecido com medula óssea autógena.Vinte e um coelhos foram sacrificados e tiveram seus ossos parietais retirados, criopreservados e irradiados com irradiação gama em dose de 50kGy. Os aloenxertos foram implantados em defeitos nos crânios de vinte e um receptores. À esquerda implantava-se o aloenxerto ósseo puro e à direita o aloenxerto adicionado de medula óssea autógena. Os coelhos foram sacrificados em duas, cinco e dez semanas e os enxertos submetidos à análise macroscópica e histomorfométrica. Todos os enxertos apresentavam-se fixos ao leito. Os parâmetros histomorfométricos não mostraram diferenças estatisticamente significante.<br>Searching for alternatives to autogenous bone graft in craniofacial reconstructions, it is proposed deep-frozen, irradiated calvarial bone allograft added with autogenous bone marrow utilization. Twenty and one rabbits were sacrificed and their parietal bones harvest, deep-frozen and gamma irradiated with 50kGy. The allografts were implanted in twenty one other rabbits. At left side only allograft were placed, at right side were put allografts added with autogenous bone marrow. The animals were sacrificed in two, five and ten weeks. Macroscopical examination showed all grafts fixed at the host bone, the histomorphometric analysis did not showed significant statistical differences between the left and right sides.
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Borgström, Simon, and Per Emmerberg. "Svek & skam : En socialpsykologisk studie om upplevelsen av att bli bedragen." Thesis, Uppsala universitet, Sociologiska institutionen, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-201143.
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Uppsatsen syftar till att redogöra för den subjektiva upplevelsen av att bli bedragen i en nära relation och är således en fenomenologisk ansats. Undersökningen har baserats på tre kvalitativa intervjuer, där de intervjuade redogjort för sin subjektiva upplevelse av att bli bedragen samt definierat begreppet otrohet. Vi har utgått från teorier om skam, skuld och stigma för att kartlägga hur upplevelsen påverkat självet. Scheffs teorier om sociala band har använts för att beskriva påverkan på individens förhållanden till andra. Vi har upptäckt att en monogam relation inte är ett krav för att otrohet ska uppfattas. Det har även framgått att omgivningens reaktioner spelar roll, på så sätt att de antingen sökte stöd från vänner, eller aktivt undanhöll ämnet från dem. Vidare har vi även upptäckt att intervjupersonerna som blivit bedragna tenderar att skuldbelägga sig själva, känna skam över händelsen samt utveckla en starkare grad av svartsjuka – som en förändring av självet.<br>Based on three qualitative interviews, our research has set out to phenomenologically describe the experience of being cheated on (or in other words, infidelity). The three people we interviewed were to describe their subjective experiences and also provide their own definition of what they considered to be infidelity. Theories on shame, guilt and stigma has been used to describe the experience's implications ”the self”. The theory of ”Social bonds” by Scheff has been used to describe implications on social relationships. We've discovered that infidelity can take place even in a relationship that's not monogamous. We've also discovered that the reaction from others plays a big part - the persons either sought support among friends, or actively withheld information from them. The effects the experience had on the persons' self were the following: they tended to blame themselves, feel shameful about the incident and after the infidelity had occurred, developed stronger feelings of jealousy.
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Reinwald, Michael. "Wave propagation in mammalian skulls and its contribution to acoustic source localization." Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS244.
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La précision avec laquelle le dauphin localise les sources sonores est excellente, que les sources soient situées dans le plan médial ou dans le plan transverse. Cette faculté est contre-intuitive étant donné que les dauphins n’ont pas d’oreille externe (pavillon), qui joue un rôle important chez les autres mammifères pour la localisation de sources en élévation. Dans cette thèse, des simulations tridimensionnelles ont été réalisées pour déterminer l’influence de la conduction osseuse du son dans le crâne d’un dauphin commun à bec court sur la pression acoustique au voisinage de l’oreille. La modalisation n’a pas permis de mettre en évidence d’encoches spectrales telles que celles créées par le pavillon de l’oreille externe des humains et qui codent chez celui-ci l’élévation de la source sonore. Une série d’expériences sur un crâne de dauphin, immergé dans une piscine, a permis de mesurer directement la conduction osseuse dans la mandibule. Les formes d’ondes complètes des sons reçus aux récepteurs fixés sur la mandibule, et particulièrement la coda du signal, a pu être utilisée avec succès pour obtenir la position de sources en utilisant un algorithme de corrélation. Ce résultat, qui devra être conforté par la réalisation d’autres expériences, suggère que le système auditif du dauphin pourrait utiliser la coda des signaux reçus lors de l’écholocation. Enfin, des simulations 2D ont permis de mettre en évidence le potentiel bénéfice du couplage de la conduction osseuse du son avec la propagation dans des structures graisseuses de la tête du dauphin<br>The spatial accuracy of source localization by dolphins has been observed to be equally accurate independent of source azimuth and elevation. This ability is counter-intuitive if one considers that humans and other species have presumably evolved pinnae to help determine the elevation of sound sources, while cetaceans have actually lost them. In this work, 3D numerical simulations are carried out to determine the influence of bone-conducted waves in the skull of a short-beaked common dolphin on sound pressure in the vicinity of the ears. The skull is not found to induce any salient spectral notches, as pinnae do in humans, that the animal could use to differentiate source elevations in the median plane. Experiments are conducted in a water tank by deploying sound sources on the horizontal and median plane around a skull of a dolphin and measuring bone-conducted waves in the mandible. Their full waveforms, and especially the coda, can be used to determine source elevation via a correlation-based source localization algorithm. While further experimental work is needed to substantiate this speculation, the results suggest that the auditory system of dolphins might be able to localize sound sources by analyzing the coda of biosonar echoes. 2D numerical simulations show that this algorithm benefits from the interaction of bone-conducted sound in a dolphin's mandible with the surrounding fats
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Petit, Mikael. "Impacts balistiques crâniens osseux, l'expérimentation au service de l'enquête." Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAD030/document.
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La balistique lésionnelle, carrefour de l’expertise balistique et de la médecine légale, est fréquemment confrontée à l’évaluation et la caractérisation de plaies balistiques crâniennes. De nombreuses recherches ont été effectuées sur les traumatismes de l’extrémité cervico-céphaliques dans une vision d’amélioration de la sécurité mais celles dans le domaine de la balistique sont quasi inexistantesou empreintes de certitudes non démontrées. Le premier objectif de ce travail a été demettre en place un protocole de tirs d’essai sur des voutes crâniennes d’animal dont la structure est comparable à celle de l’homme. Ce setup original, alliant la technologie d’enregistrement vidéo à haute vitesse et l’analyse des dégâts en microtomographie, a permis de mettre en exergue des relations entre vitesse d’impact, vitesse de sortie, énergie dissipée et dommages créés. Ils contredisent souvent certaines théories jusque là proposées et répondant ainsi à notre deuxième objectif. Les nombreuses données acquises par l’expérimentation pourront utilement éclairer l’expert en balistique lésionnelle dans l’argumentation de ses hypothèses quant à l’utilisation d’un couple arme-munition plutôt qu’un autre. Cette étude propose également un nouveau modèle quant à la cinématique complète de l’interaction entre le projectile et la structure osseuse<br>Wound ballistics is at the crossing between ballistics and legal medicine. It frequently has to tackle skull gunshot wounds evaluation and characterization. Many researches have been made around head and skull traumas, aiming at an improvement of security devices, but considering the field of ballistics, researches are either inexistent or marred by undemonstrated certainties. This work first aims at setting a firing protocol out, using animal skull bones that are similar with humans’. This original setup allies high speed video recordings and damage analysis with microtomography. It has shown up relationships between impact speed, exit speed, dissipated energy and observed damages. It comes in contradiction with many models formerly exposed, and hence fulfills our second objective. Important data acquired from experiments can show as very useful for wound ballistics expert to support one of his hypothesis about which firearms and ammunition type were used. This work eventually proposes a new model explaining the interaction between projectile and bone structure during damage creation
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Marchini, Monikelly do Carmo Nascimento 1986. "Influência do grau de rotação do aparelho e do crânio na espessura da cortical óssea em imagens de tomografia de feixe cônico : Evaluation of the influence of the unit and skull rotation on cortical bone thickness in cone beam computed tomography images." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/290162.
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Orientador: Solange Maria de Almeida Bóscolo<br>Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba<br>Made available in DSpace on 2018-08-24T18:23:38Z (GMT). No. of bitstreams: 1
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Previous issue date: 2014<br>Resumo: A tomografia computadorizada de feixe cônico (TCFC) tem sido uma ferramenta de auxílio no diagnóstico, com várias aplicações clínicas. Devido ao aumento das diversas possibilidades de aquisição da imagem, há uma grande necessidade de um constante ajuste da imagem para cada proposta de diagnóstico. A avaliação da cortical óssea é importante para os casos de planejamento de implante imediato e para os casos em que há a necessidade de movimentação ortodôntica extensa. Entretanto, alguns fatores de qualidade de imagem devem ser considerados para uma acurada visualização da cortical óssea. Assim, com o presente estudo avaliou a influência do grau de rotação do aparelho, 3600 e 1800, bem como a influência de diferentes posições do crânio na avaliação da espessura da cortical óssea em imagens de TCFC. Para tanto, foram utilizados 11 crânios de humanos nos quais foram selecionados 59 dentes da maxila e mandíbula para avaliação de suas corticais ósseas. As imagens foram adquiridas no aparelho de TCFC Accuitomo 170, com voxel de 0,16mm, em quatro diferentes aspectos com relação à rotação do aparelho e posição do crânio respectivamente (protocolo 1: 3600/00; protocolo 2: 1800/00; protocolo 3: 1800/900; protocolo 4: 1800/1800). Para a avaliação das imagens, a cortical óssea foi classificada em três grupos de acordo com a condição ou espessura (cortical ausente, cortical fina e cortical espessa). No total 472 imagens bidimensionais (2D), referentes a cortes sagitais, foram avaliadas por três radiologistas previamente calibrados. Para concordância intra e interobservador foi utilizado o teste kappa e para avaliação das espessuras das corticais ósseas em relação ao real e entre os diferentes tipos de imagem foi utilizado o teste de Wilcoxon Signed Ranks. O teste de Kappa ponderado foi utilizado para comparar as diferentes condições da espessura óssea nos quatro protocolos de imagem. O nível de significância estabelecido foi de 95% (?=0,05). Os resultados obtidos mostraram que a concordância intraobservador variou de quase perfeita (k=0,87) a moderada (k=0,50) e a concordância interobservador variou de substancial (k=0,79) a moderada (k=0,56). De acordo com os resultados obtidos, observou-se que apenas para o protocolo 1 na região da cortical lingual, não houve diferença estatística entre as imagens e o padrão-ouro. Quando avaliando a cortical lingual, os maiores valores de concordância foram observados no protocolo 3, quando esta era ausente (k=0,80) e fina (k=0,47), já para cortical lingual espessa, o mais concordante foi o protocolo 2 (k=0,60). Avaliando-se somente a cortical vestibular, quando esta era ausente, o protocolo 3 exibiu o maior valor de concordância (k=0,61), enquanto que o protocolo 4 foi o mais concordante para cortical vestibular fina (k=0,38) e o protocolo 2 para a cortical vestibular espessa (k=0,40). Concluiu-se que o diagnóstico da espessura da cortical óssea não apresenta concordância perfeita com as imagens de TCFC, exceto para a região da cortical lingual no protocolo 1. Houve uma maior dificuldade de diagnóstico para a cortical vestibular em relação a lingual. Além disso, quando a espessura é mais fina, mais difícil é o diagnóstico<br>Abstract: The cone beam computed tomography (CBCT) has been a complement tool in diagnosis of many clinical applications. Due to the increase of the various possibilities of imaging, there is a great need for an image adjustment for each proposal to be diagnosed. The evaluation of cortical bone is important for implants pos-extraction placement and in cases requiring extensive orthodontic movement. However, some factors of image quality should be considered for accurate visualization of cortical bone. Thus, this study aimed to evaluate the influence of the arc rotation (3600 and 1800), and the influence of different positions of the skull to assess the thickness of buccal and lingual cortical bone in CBCT images. For this, 59 teeth of 11 human skulls in both arcs were selected. Images were made on Accuitomo 170 CBCT. The voxel size used was 0.16 mm. Four different aspects of image regarding the rotation of the device and position of the skull were made respectively (protocol 1: 3600/00; protocol 2: 1800/00; protocol 3: 1800/900; protocol 4: 1800/1800). For evaluation of the images, the cortical bone was classified into three groups according to the condition or the thickness (absent cortical, thin cortical, and thick cortical). A total of 472 two-dimensional images (2D) in sagittal sections were evaluated by three radiologists previously calibrated. For intra- and interobserver agreement kappa test was used. Wilcoxon Signed Ranks test was used to assess the cortical bone thickness compared to the gold standard and among different protocols. Ponderate Kappa test was used to compare conditions of cortical bone among protocols. The significance level was set at 95% (?=0.05). The results showed that the intraobserver agreement ranged from almost perfect (k=0.87) to moderate (k=0.50) and interobserver agreement ranged from substantial (k=0.79) to moderate (k=0.56). According to the results obtained, the protocol 1 showed that no statistical difference between the images and the gold standard was found only in lingual cortical bone region. When evaluating lingual cortical, higher reliability values was found with protocol 3 for absent (k=0.80) and thin (k=0.47), while for thick cortical in lingual side, the more consistent was the protocol 2 (k=0.60). Evaluating only buccal cortical side, the protocol 3 obtained the best agreement value for absent, (k=0.61), while the protocol 4 was better for thin cortical in buccal side (k=0.38), and protocol 2 for thick cortical in buccal side (k=0.40). It was concluded that the diagnosis of cortical bone thickness do not show agreement with CBCT images, except for lingual cortical bone in the protocol 1. There was more difficult diagnosis in buccal cortical compared to lingual cortical side. In addition, when the thickness is thinner more difficult the diagnosis is<br>Doutorado<br>Radiologia Odontologica<br>Doutora em Radiologia Odontológica
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Eklund, Magdalena, and Lisa Hansson. "Det dubbla straffet : Mödrar på anstalt." Thesis, Högskolan i Halmstad, Sektionen för hälsa och samhälle (HOS), 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-14658.
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Vi möter i denna uppsats kvinnor som successivt förändrar vår bild av det dubbla straffet, som komplicerar vår uppfattning om ett liv i missbruksberoende och livet på kvinnoanstalt, men som också förenklar föreställningen om den djupa kärleken de hyser för sina barn. Eftersom dessa mödrar har arbetat en hel del med sig själva och tagit sig ur långa perioder av beroende har vi fått känna av den kraft som lösgörs då en människa verkar inom någonting hon brinner för. Att hjälpa andra och att tillåta sig själv att ta emot hjälp har guidat denna berättelse kring människans förmåga att resa sig och gå vidare. Det faktum att kärleken tycks verka sida vid sida med den skuldtyngda problematiken har väckt vårt intresse och diskuteras genom texten som en löpande röd tråd. Genom att låta de individuella känslorna möta sociologiska teorier vidgas perspektivet till en vinkel som berör såväl makro som mikronivå i samhället. Den här uppsatsen försöker förklara sambanden såväl som de inkompatibla rollerna och dess konsekvenser för mödrar i fängelse. Thomas J Scheffs teori om sociala band leder diskussionen och är avgörande för att förstå behovet av hänsynstagande liksom den förödande skammens inverkan på individ och samhälle. Mänsklig mångfald och flerfaldiga verklighetsuppfattningar finner mening i en socialpsykologisk tolkning och analys sprungen ur en innovativ undersökning.<br>In this study we meet women who gradually change our picture of the "double penalty", which complicates our view of a life of abuse and drug dependence, and the life in a women’s prison, but also simplifies the notion of the deep love they have for their children. Since these mothers have worked a lot with themselves and emerging from long periods of drug dependence, we have experienced the force which is released when someone is working with something she is passionate about. To help others and to allow the individual to accept help has guided this story about the human beings ability to get up and move on. The fact that the love seems to work side by side with the indebted problem has aroused our interest and is discussed in the text as a running theme. By allowing the individual emotions to meet sociological theories widens the perspective to an angle involving both macro- and micro-levels of society. This essay tries to explain the relationships as well as the incompatible roles and its impact on mothers in prison. Thomas J. Scheff's theory of social bonds is leading the discussion and is critical to understanding the need for consideration as well as the devastating impact of shame on the individual and society. Human diversity and multiple views of reality will find meaning in a social psychological interpretation and analysis originated from an innovative study.
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Gros, Catherine-Isabelle. "Dysplasie ectodermique hypohidrotique : mise en évidence de nouveaux marqueurs phenotypiques crâniens et post-crâniens chez le mutant Tabby." Thesis, Strasbourg, 2013. http://www.theses.fr/2013STRAJ101/document.
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La Dysplasie Ectodermique Hypohidrotique liée à l'X (DEX) est une maladie génétique liée à une mutation du gène EDA. Le phénotype exprimé par le modèle murin Tabby est l'équivalent de celui observé dans l'espèce humaine et présente des anomalies dentaires, cranio-faciales, vertébrales et des défauts de trabéculation osseuse. Dans ce contexte, une cartographie de ces anomalies chez le mutant Tabby était nécessaire et l'analyse de l’impact de la mutation Eda/Ta sur la croissance du squelette crânien et post-crânien a été étudiée. Un suivi longitudinal d'une cohorte d'individus murin Tabby (5 mâles hémizygotes EdaTa/Y, 6 femelles hétérozygotes EdaTa/+) et sauvages (n=12) a été réalisé à partir d’une succession d’acquisitions TDM pendant plus de 2 ans. L'observation des profils de croissance et de leurs paramètres a montré des anomalies de croissance du complexe crânio-facial, de la base du crâne (hypo-développement crânien) et un déficit de croissance relatif des os longs (fémur et humérus) chez les souris hémizygotes EdaTa/Y. Ces résultats mettent pour la première fois en évidence des anomalies de développement des os longs et confirment le rôle d’EDA-A dans la formation normale du squelette. Ces données constituent un pré-requis essentiel pour tester l’efficacité de tentatives de réversion phénotypique à partir de protéines recombinantes<br>X-linked Hypohidrotic Ectodermal Dysplasia (XLHED) is a genetic disorder due to a mutation of the EDA gene. The phenotype expressed by Tabby mice, murine model of XLHED, is equivalent to that observed in humans including dental anomalies, craniofacial and vertebral trabecular bone defects. In this context, a mapping of these anomalies in Tabby mice was necessary and the impact of the EdaTa mutation on cranial and post -cranial skeletal growth was studied. A 2 years (112 weeks) μCT follow-up of Tabby mice (5 hemizygous males EdaTa/Y, 6 heterozygous females EdaTa/+) and Wild Type group (n = 12) hasbeen performed. The observation of growth patterns and parameters showed a relative cranial hypodevelopment, abnormal growth of the craniofacial complex and a relative hypo-development of appendicular skeleton (femur and humerus) in Tabby mice. These results allowed for the first time to highlight appendicular developmental abnormalities, confirming the role of EDA-A in the normal formation of the skeleton. While enriching the phenotypic picture of this syndrome, in a therapeuticperspective, all of these data are an essential prerequisite to test the effectiveness of attempts to phenotypic reversion from recombinant proteins
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Yosef, Sonia, and Julia Sommer. "High Yield – A Late Bloomer’s Time To Shine?" Thesis, KTH, Fastigheter och byggande, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-191509.
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Real estate companies are capital intense and bank loans represent the most common source of funding. However, the years following the latest financial crisis resulted in difficult terms and expensive bank loans, which cleared a path for alternative sources of funding. Small and me-dium-sized real estate companies displayed a particular interest in corporate bonds and ever since then the real estate sector have been overrepresented on the Swedish corporate bond mar-ket. Despite the growth during the past years, the Swedish market still appears to be underde-veloped compared to other countries. However, several trends are now indicating that High Yield is on the rise. New regulations that are currently being implemented will increase the costs for banks further and consequently make bank loans even more expensive. Simultane-ously, the current low interest-rate environment and volatile stock markets are increasing de-mand for High Yield alternatives among retail and institutional investors. This study investi-gates the High Yield market for small and medium-sized real estate companies and is built upon eleven interviews with professionals. It concludes that the market is underdeveloped because there has been no previous demand for it. Swedish banks and companies have traditionally had a synergetic relationship while investors relied on saving accounts and equities. The situation today is different; investors are demanding High Yield investments and the segment will most probably increase in the future. Real estate companies are positive to bonds and wish to increase the current ratio of their debt portfolio. There are however several barriers for continued growth, such as lack of knowledge, transparency, liquidity as well as fair pricing in the market. In the current state, corporate bond investments are suitable only for professional investors. The ex-emption is High Net Worth Individuals, who buy and hold, which are particularly suited for smaller corporate bonds.<br>Fastighetsföretag bedriver kapitalintensiv verksamhet och den vanligaste finansieringsformen för svenska fastighetsföretag är idag banklån. Efter den senaste finanskrisen har dock bankut-låningen blivit mer restriktiv vilket särskilt har drabbat mindre företag. Till följd av detta har alternativa finansieringsformer blivit allt vanligare där företagsobligationer blivit särskilt in-tressanta för små och medelstora fastighetsföretag. Sedan finanskrisen har specifikt fastighets-företagen varit överrepresenterade på den svenska företagsobligationsmarknaden. Faktum är ändock att företagsobligationsmarknaden i Sverige, trots tillväxt de senaste åren, framstår som underutvecklad i jämförelse med andra länder. Flertalet trender pekar emellertid på att den kom-mer att fortsätta blomma ut. För närvarande implementeras nya regelverk som ökar kostnaderna för bankerna och potentiellt kommer att leda till större restriktioner och dyrare banklån. Vidare bidrar dagens låga ränteläge i kombination med volatila aktiemarknader till att efterfrågan på företagsobligationer bland investerare, privata såväl som institutionella, ökar. Studien undersö-ker företagsobligationsmarknaden inom High Yield segmentet för små och medelstora fastig-hetsföretag och bygger på elva intervjuer med yrkesverksamma. Det konkluderas att marknaden är underutvecklad då den ej har efterfrågats tidigare. De svenska bankerna och fastighetsföre-tagen har sedan länge en symbiotisk relation samtidigt som investerare har förlitat sig på spar-konton och aktier. Idag är situationen annorlunda där fler investerare efterfrågar High Yield produkter. Fastighetsföretagen är positiva till obligationer och önskar öka nuvarande andel i sina skuldportföljer. Det finns dock barriärer för den fortsatta tillväxten på marknaden, där-ibland brist på kunskap, transparens och likviditet samt ifrågasatt prissättning. Direktinveste-ringar i företagsobligationer idag lämpar sig därför för professionella investerare. Undantaget är kapitalstarka privatpersoner som ämnar att hålla instrumentet till förfall vilka lämpar sig sär-skilt bra som investerare i mindre företagsobligationer.
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LIU, YU-CIH, and 劉于慈. "Scenes with Bones：“Imagery of Skull” Applied in the New Media Arts through the Digital Moving Image Creations." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/e6hvbw.
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碩士<br>國立臺灣藝術大學<br>視覺傳達設計學系<br>103<br>As a visual symbol inseparable from human society, the form of “the image of a skull” has a history of thousands of years and across different regions in the world. With the development of civilization and the changing of society, the cultural meaning of the “imagery of skull” has always been expanding. Connecting the two extremes - “life” and “death”, “the imagery of skull ” becomes an important metaphor and visualized symbol in the field of art. People often use skull images as a medium to discuss the issues surrounding life. The differences of the skull image in history show the change in people’s understanding of life and being, as well as in the core values of society.
Image technologies and new media arts are flourishing in the 21st century, which have great effects on modern life and contemporary art. Because of its five characteristics, such as “numerical representation, modularity, automation, variability, transcoding”, digital images become the dominant form of images in the modern era. The reproductability of contemporary images leads to the hyperreal scenes of modern society where images are produced, copied and stimulated in a way that mimetic cannot be told apart from the original.
My study focuses on the traditional art theme of “the imagery of skull”, as it is applied in new media art and digital moving images. I intend to use different techniques and materials to create five digital moving images. The five pieces of artwork together seek to accomplish the semiotic analysis of the skull image. Theoretically this study is influenced by Roland Barthes’s denotation and connotation theories. In this study I emphasize the socio-historical context of art and the artist’s point of view in a conventional theme of art, in the hope to find new angles of interpretation of the “imagery of skull” in modern times.
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Dufton, Megan. "EARLY LENS ABLATION CAUSES DRAMATIC LONG TERM EFFECTS ON THE BONES OF THE CRANIOFACIAL SKELETON OF THE MEXICAN TETRA, ASTYANAX MEXICANUS." 2013. http://hdl.handle.net/10222/21844.
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The Mexican tetra, Astyanax mexicanus, exists as two morphs of a single species, a sighted surface morph and a blind cavefish. In addition to eye regression, cavefish have an increased number of taste buds, maxillary teeth and have an altered craniofacial skeleton. I investigated the effect the lens has on the development of the surrounding skull by ablating the lens over early ontogeny. This unique long-term study sheds light on how early embryonic manipulations on the eye can affect the shape of the adult skull. The effects of lens ablation were analyzed using landmark based morphometric analyzes. Morphometric analyzes indicate that there is a significant difference in the shape of the supraorbital bone and suborbital bones four through six. These bones expand into the eye orbit exhibiting variability in their shape. Interestingly, the number of caudal teeth on the lower jaw is also affected by lens ablation. I compared these findings between morphs and across two teleost species. I conducted lens removal in the surface fish to determine if it would produce a cavefish phenotype. Lens removal in the surface fish only partially results in a cavefish phenotype, indicating that lens loss is not solely responsible for the phenotypic differences between the two morphs. The effects of lens removal were then compared in the Mexican tetra and zebrafish. Surprisingly, the results indicate that the same bones are variable in shape in both species, indicating that the variability of these bones is conserved across species. Finally, I compared laser lens damage and full lens removal, to investigate the capacity for both lens regeneration and healing in the Mexican tetra.
Together, the lens healing and regeneration studies indicate that lens absence in early development does not influence the shape of the skull. Lens absence during later development influences the mechanical forces in the skull resulting in the bones of the orbital region changing in size and shape. This study highlights the dynamic nature of the skull and sheds light on the influence the eyes (a soft tissue) have on the surrounding skull (a hard tissue) a topic which has been overlooked in the literature.
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Kim, Heawon Ludia. "Anthropometric patterns of craniofacial growth in cleft lip and palate human prenates a thesis submitted in partial fulfillment ... for the degree of Master of Science (Orthodontics) /." 1997. http://catalog.hathitrust.org/api/volumes/oclc/68799444.html.
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Castanhinha, Rui Alexandre Ferreira. "Developmental and paleontological insights into skull bone homology and evolution." Doctoral thesis, 2014. http://hdl.handle.net/10362/17382.
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The Gallus gallus (chicken) embryo is a central model organism
in evolutionary developmental biology. Its anatomy and developmental
genetics have been extensively studied and many relevant evolutionary
implications have been made so far. However, important questions
regarding the developmental origin of the chicken skull bones are still
unresolved such that no solid homology can be established across
organisms. This precludes evolutionary comparisons between this and
other avian model systems in which skull anatomy has evolved
significantly over the last millions of years.(...)
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Matos, Paula Catarina Silva de. "Testing macroevolutionary skull patterns using tetrapod cranial networks." Master's thesis, 2018. http://hdl.handle.net/10773/25776.
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The vertebrates’ skull houses the brain and important sensory organs. This anatomic structure has suffered various changes and specializations that recapitulate the evolutionary process. This variability, its complexity and easy preservation makes it one of the standard characteristics used in comparative anatomy and evolutive biology for instance in the classification of vertebrates and phylogenetic reconstruction.
A total of 25 species were considered: Acanthostega gunnari; 14 species within Mammalia including the groups Sirenia, Hyracoidea, Carnivora, Cetartiodactyla and Primates and 10 Reptilia from Crocodylia, Neotheropoda, Rhynchocephalia, Squamata and Testudines.
All the collected data was analyzed through three different softwares: PAUP, for phylogenetic analysis, Gephi to build networks of contacts from the skull and Rstudio for statistics.
In this study we show how phylogeny of an animal can be inferred to Class level using exclusively information regarding skull bone contacts but there is not enough information contained on the skull alone to recreate phylogenetic paths to build complete phylogeny.<br>No corpo dos vertebrados o crânio aloja o cérebro e diversos órgãos sensoriais importantes. Esta estrutura anatómica passou por várias modificações e especializações que recapitulam o processo evolutivo. O facto de ser muito variável, complexo e de fácil preservação torna-o uma estrutura comummente utilizada em anatomia comparada e em estudos de biologia evolutiva, nomeadamente para a classificação de vertebrados e reconstruções filogenéticas.
Na análise aqui apresentada consideramos um total de 25 espécies: Acanthostega gunnari; 14 espécies dos Mammalia incluindo os grupos Sirenia, Hyracoidea, Carnivora, Cetartiodactyla e Primatas e 10 Reptilia distribuídos entre Crocodylia, Neotheropoda, Squamata, Rhynchocephalia e Testudines.
Todos os dados recolhidos foram analisados em três softwares diferentes: PAUP, para uma análise filogenética, Gephi para construir redes de contactos dos ossos do crânio e Rstudio para aferir dados estatísticos.
No presente trabalho mostramos que a filogenia de um animal pode ser inferida até ao nível da classe usando somente dados de contactos cranianos, no entanto, não é suficiente para reconstruir árvores filogenéticas.<br>Mestrado em Ecologia Aplicada
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Yi-ChingWang and 王怡晴. "Effect of BM matrix on repairing a skull bone defect in rabbits." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/uy27ze.
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Engelke, Katharina [Verfasser]. "Intravital multiphoton microscopy analysis of spatial relationships in murine skull bone marrow / vorgelegt von Katharina Engelke." 2009. http://d-nb.info/997421991/34.
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Büster, Lindsey S., Karina T. Croucher, Jennifer E. Dayes, Laura I. Green, and C. Faull. "From Plastered Skulls to Palliative Care: What the Past Can Teach Us About Dealing with Death." 2018. http://hdl.handle.net/10454/16695.
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Yes<br>Modern, advanced healthcare detects and monitors long-term
and life-limiting illness more comprehensively than ever before.
However, death is now often considered medical failure, and is a
virtually taboo topic of conversation in daily life. At a time when the
societal relevance of archaeology is under scrutiny more than ever
before, the AHRC-funded Continuing Bonds Project – a collaboration
between archaeology and palliative care – explores the potential
of the past to promote discussion. Not only does archaeology
illuminate the diversity of practice surrounding death, the past
provides a safe, distanced platform for considering death, dying
and bereavement today. Through archaeological and ethnographic
case studies, health and social care professionals and students
consider topics such as place, choice and identity, in both personal
and professional life. This article examines participant responses
to a variety of archaeological material and presents post-workshop
reflections which demonstrate the success of archaeology in
opening up conversations and increasing confidence in discussing
this most enduring and problematic of life events.<br>Arts and Humanities Research Council
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(8102429), Xuedong Zhai. "MECHANICAL BEHAVIORS OF BIOMATERIALS OVER A WIDE RANGE OF LOADING RATES." Thesis, 2019.
Find full textAbstract:
<div>The mechanical behaviors of different kinds of biological tissues, including muscle tissues, cortical bones, cancellous bones and skulls, were studied under various loading conditions to investigate their strain-rate sensitivities and loading-direction dependencies. Specifically, the compressive mechanical behaviors of porcine muscle were studied at quasi-static (<1/s) and intermediate (1/s─10^2/s) strain rates. Both the compressive and tensile mechanical behaviors of human muscle were investigated at quasi-static and intermediate strain rates. The effect of strain-rate and loading-direction on the compressive mechanical behaviors of human frontal skulls, with its entire sandwich structure intact, were also studied at quasi-static, intermediate and high (10^2/s─10^3/s) strain rates. The fracture behaviors of porcine cortical bone and cancellous bone were investigated at both quasi-static (0.01mm/s) and dynamic (~6.1 m/s) loading rates, with the entire failure process visualized, in real-time, using the phase contrast imaging technique. Research effort was also focused on studying the dynamic fracture behaviors, in terms of fracture initiation toughness and crack-growth resistance curve (R-curve), of porcine cortical bone in three loading directions: in-plane transverse, out-of-plane transverse and in-plane longitudinal. A hydraulic material testing system (MTS) was used to load all the biological tissues at quasi-static and intermediate loading rates. Experiments at high loading rates were performed on regular or modified Kolsky bars. Tomography of bone specimens was also performed to help understand their microstructures and obtain the basic material properties before mechanical characterizations. Experimental results found that both porcine muscle and human muscle exhibited non-linear and strain-rate dependent mechanical behaviors in the range from quasi-static (10^(-2)/s─1/s) to intermediate (1/s─10^2/s) loading rates. The porcine muscle showed no significant difference in the stress-strain curve between the along-fiber and transverse-to-fiber orientation, while it was found the human muscle was stiffer and stronger along fiber direction in tension than transverse-to fiber direction in compression. The human frontal skulls exhibited a highly loading-direction dependent mechanical behavior: higher ultimate strength, with an increasing ratio of 2, and higher elastic modulus, with an increasing ratio of 3, were found in tangential loading direction when compared with those in the radial direction. A transition from quasi-ductile to brittle compressive mechanical behaviors of human frontal skulls was also observed as loading rate increased from quasi-static to dynamic, as the elastic modulus was increased by factors of 4 and 2.5 in the radial and tangential loading directions, respectively. Experimental results also suggested that the strength in the radial direction was mainly depended on the diploë porosity while the diploë layer ratio played the predominant role in the tangential direction. For the fracture behaviors of bones, straight-through crack paths were observed in both the in-plane longitudinal cortical bone specimens and cancellous bone specimens, while the cracks were highly tortuous in the in-plane transverse cortical bone specimens. Although the extent of toughening mechanisms at dynamic loading rate was comparatively diminished, crack deflections and twists at osteon cement lines were still observed in the transversely oriented cortical bone specimens at not only quasi-static loading rate but also dynamic loading rate. The locations of fracture initiations were found statistical independent on the bone type, while the propagation direction of incipient crack was significantly dependent on the loading direction in cortical bone and largely varied among different types of bones (cortical bone and cancellous bone). In addition, the crack propagation velocities were dependent on crack extension over the entire crack path for all the three loading directions while the initial velocity for in-plane direction was lower than the other two directions. Both the cortical bone and cancellous bone exhibited higher fracture initiation toughness and steeper R-curves at the quasi-static loading rate than the dynamic loading rate. For cortical bone at a dynamic loading rate (5.4 m/s), the R-curves were steepest, and the crack surfaces were most tortuous in the in-plane transverse direction while highly smooth crack paths and slowly growing R-curves were found in the in-plane longitudinal direction, suggesting an overall transition from brittle to ductile-like fracture behaviors as the osteon orientation varies from in-plane longitudinal to out-of-plane transverse, and to in-plane transverse eventually.</div>