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Relação da otite média secretora com o crescimento craniofacial e as características oclusais / The relationship of otitis media with effusion to the craniofacial growth and occlusal featuresClaudio de Gois Nery 13 August 2008 (has links)
O objetivo deste estudo foi avaliar a morfologia/crescimento craniofacial e a oclusão dentária em pacientes (ambos sexos), entre 4 e 10 anos e aumento adenoamigdaliano com e sem otite média secretora (OMS). Utilizou-se análise cefalométrica e modelos de estudo dentários. Não foram observadas diferenças significativas entre os grupos estudados, em relação às medidas lineares e angulares adotadas, exceto, a medida correspondente ao comprimento do palato ósseo (ENA-ENP), que mostrou relação com a idade e a OMS. Não houve um tipo facial predominante. Observou-se discreta predominância de mordida profunda, mordida cruzada posterior e desvio da linha média em relação à OMS, porém sem significância estatística. A atresia maxilar pode estar associada à OMS, assim como sua redução pode estar relacionada ao crescimento e desenvolvimento craniofacial / The aim of this study was to evaluate the craniofacial growth/morphology and dental occlusion in 100 patients (male and female) from 4 to 10 years old and tonsils and adenoid enlargement. There were two groups: with and without otitis media with effusion (OME). We used the cephalometric analyses and dental casts. It was not observed significant differences between the two groups, in relationship to the linear and angular measurements adopted, except for the measurement corresponding to the palate bone length, which had shown correlation with age and OME. It was not found a facial pattern predominance. It was observed a discreet predominance of deep bite, posterior cross bite and midline deviation to OME, however without statistical significance. The maxillary narrowing might be associated to OME as well as its reduction may be related to the craniofacial growth and development
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Determinação do melhor método para prever o alcance à junção craniovertebral nas cirurgias endoscópicas transnasais utilizando neuronavegação / Definition of the best method to predict the extent of endoscopic transnasal surgery to the cranio vertebral junction using neuronavigationAurich, Lucas Alves 31 March 2017 (has links)
Espera-se redução das complicações cirúrgicas quando lesões localizadas na junção craniovertebral (JCV) são operadas pelo acesso cirúrgico endoscópico transnasal ao invés do acesso transoral. Entretanto, não se sabe ainda qual seria o maior alcance inferior da abordagem transnasal e também qual seria o melhor método para prever o limite de exposição no planejamento pré-operatório. No presente estudo, o alcance à JCV foi definido no período intraoperatório com neuronavegação em 10 pacientes operados pela via transnasal. O limite anatômico obtido foi comparado com as linhas nasopalatina e palatina. A linha nasopalatina mostrou ser o melhor método para prever o alcance inferior à JCV. / It is expected reduction of surgical complications when craniovertebral junction pathologies are operated using the endoscopic transnasal approach instead of the transoral approach. However, it is yet unclear what is the lower extent of the transnasal approach and which method is better to predict this lower limit in preoperative planning. This study evaluates the inferior exposure of craniocervical junction in 10 patients operated through the transnasal approach using neuronavigation. The intraoperative anatomical limit was compared to nasopalatine and palatine lines. The nasopalatine line predicts more accurately the inferior limit of the transnasal approach.
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Determinação do melhor método para prever o alcance à junção craniovertebral nas cirurgias endoscópicas transnasais utilizando neuronavegação / Definition of the best method to predict the extent of endoscopic transnasal surgery to the cranio vertebral junction using neuronavigationAurich, Lucas Alves 31 March 2017 (has links)
Espera-se redução das complicações cirúrgicas quando lesões localizadas na junção craniovertebral (JCV) são operadas pelo acesso cirúrgico endoscópico transnasal ao invés do acesso transoral. Entretanto, não se sabe ainda qual seria o maior alcance inferior da abordagem transnasal e também qual seria o melhor método para prever o limite de exposição no planejamento pré-operatório. No presente estudo, o alcance à JCV foi definido no período intraoperatório com neuronavegação em 10 pacientes operados pela via transnasal. O limite anatômico obtido foi comparado com as linhas nasopalatina e palatina. A linha nasopalatina mostrou ser o melhor método para prever o alcance inferior à JCV. / It is expected reduction of surgical complications when craniovertebral junction pathologies are operated using the endoscopic transnasal approach instead of the transoral approach. However, it is yet unclear what is the lower extent of the transnasal approach and which method is better to predict this lower limit in preoperative planning. This study evaluates the inferior exposure of craniocervical junction in 10 patients operated through the transnasal approach using neuronavigation. The intraoperative anatomical limit was compared to nasopalatine and palatine lines. The nasopalatine line predicts more accurately the inferior limit of the transnasal approach.
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Ätiologie und Epidemiologie der Erkrankungen des Respirationstraktes im Frühneolithikum Mitteleuropas am Beispiel der linearbandkeramischen Population von Wandersleben: Ätiologie und Epidemiologie der Erkrankungen desRespirationstraktes im Frühneolithikum Mitteleuropasam Beispiel der linearbandkeramischen Population vonWanderslebenKlingner, Susan 18 October 2016 (has links)
Über die Ätiologie und Epidemiologie der Erkrankungen des Respirationstraktes im Frühneolithikum Mitteleuropas gibt es bislang keine umfassenden Studien. Die Häufigkeit, mögliche Geschlechts- und Altersunterschiede, Populationsunterschiede und Erkenntnisse über mögliche Ursachen und auslösende Faktoren der Atemwegserkrankungen zur Zeit der Bandkeramik sind von besonderem Interesse. Zudem soll aufgezeigt werden wie wichtig es ist, alle Strukturen zu untersuchen, die den „knöchernen Respirationstrakt“ repräsentieren. Von den ersten Ackerbauern und Viehzüchtern aus Wandersleben (Thüringen, Kreis Gotha) lagen insgesamt 112 erwachsene Individuen zur Untersuchung vor. Rippen und Schädel wurden mit paläopathologischen Methoden untersucht. Diese waren neben einer makroskopischen Begutachtung der Knochen, röntgenologische, endoskopische, lupenmikroskopische, lichtmikroskopische und rasterelektronenmikroskopische Untersuchungen, um eine verlässliche Diagnosestellung zu gewährleisten. 100 % (n = 71/71) der befundbaren Individuen zeigten Spuren chronischer Erkrankungen im Bereich der knöchernen Strukturen, die die oberen Atemwege umgeben. Bei 76,8% (n = 53/69) der Individuen mit befundbaren Rippen konnten Spuren von chronischen Erkrankungen aufgezeigt werden. Signifikante Geschlechts- oder Altersunterschiede bestehen insgesamt nicht. Bei der linearbandkeramischen Population aus Wandersleben ist davon auszugehen, dass es sich in vielen Fällen um Chronifizierungen von Erkältungskrankheiten und um die Folgen einer vergleichbar schlechten Luftqualität hauptsächlich im Haus handelt. Dazu haben die damaligen Lebensumstände, vor allem aber die sesshafte Lebensweise und Wirtschaftszweige mit Ackerbau und Viehzucht, maßgeblich beigetragen.:1 Einleitung ............................................................................................................................ 1
2 Material ............................................................................................................................... 3
3 Methoden ........................................................................................................................... 18
3.1 Vorarbeiten.............................................................................................................................18
3.2 Alters- und Geschlechtsbestimmung......................................................................................18
3.3 Paläopathologische Untersuchungsmethoden ........................................................................19
3.3.1 Dokumentation der erhaltenen Funde und der Befunde .................................................19
3.3.2 Makroskopische und lupenmikroskopische Untersuchung ............................................19
3.3.3 Röntgenologische Untersuchung ....................................................................................19
3.3.4 Endoskopische Untersuchung ........................................................................................19
3.3.5 Fotografie .......................................................................................................................20
3.3.6 Herstellung von Ab- und Ausgüssen ..............................................................................20
3.3.7 Rasterelektronenmikroskopische Untersuchung ............................................................20
3.3.8 Lichtmikroskopische Untersuchung ...............................................................................21
3.4 Statistik...................................................................................................................................21
3.5 Auswertung ............................................................................................................................22
4 Ergebnisse und Befunde .................................................................................................... 24
4.1 Alters- und Geschlechtsverteilung .........................................................................................24
4.1.1 Altersverteilung und Sterblichkeit ..................................................................................24
4.1.1.1 Altersverteilung der erwachsenen Individuen mit erhaltenen Schädeln ....................28
4.1.1.2 Altersverteilung der erwachsenen Individuen mit erhaltenen Rippen........................32
4.1.1.3 Altersverteilung der erwachsenen Individuen mit erhaltenen Schädeln und Rippen. 36
4.1.2 Geschlechtsverteilung ....................................................................................................41
4.1.2.1 Geschlechtsverteilung der erwachsenen Individuen mit erhaltenen Schädeln ...........47
4.1.2.2 Geschlechtsverteilung der erwachsenen Individuen mit erhaltenen Rippen ..............49
4.1.2.3 Geschlechtsverteilung der erwachsenen Individuen mit erhaltenen Schädeln und
Rippen.........................................................................................................................50
4.2 Knöcherne Schädelstrukturen ................................................................................................54
4.2.1 Begrenzung der Apertura piriformis ..............................................................................54
4.2.1.1 Anatomische Grundlagen...........................................................................................54
4.2.1.2 Veränderte Aperturae piriformes................................................................................55
4.2.1.3 Individuen mit veränderten Aperturae piriformes.....................................................66
4.2.1.4 Zur Klinik der Begrenzung der Apertura piriformis ..................................................72
4.2.1.5 Ausgewählte Fallbeispiele..........................................................................................72
4.2.1.6 Zusammenstellung der morphologischen Veränderungen an der Aperturae
piriformes..... ...............................................................................................................74
4.2.2 Nasenhöhle .....................................................................................................................78
4.2.2.1 Anatomische Grundlagen........................................................................................................ 78
4.2.2.2 Veränderte Nasenhöhlen ............................................................................................80
4.2.2.3 Individuen mit veränderten Nasenhöhlen ...................................................................90
4.2.2.4 Zur Klinik der Nasenhöhle .........................................................................................97
4.2.2.5 Ausgewählte Fallbeispiele..........................................................................................98
4.2.2.6 Zusammenstellung der morphologischen Veränderungen in der Nasenhöhle .........102
4.2.3 Sulcus lacrimalis maxillae............................................................................................106
4.2.3.1 Anatomische Grundlagen.........................................................................................106
4.2.3.2 Veränderte Sulci lacrimales maxillae.......................................................................108
4.2.3.3 Individuen mit veränderten Sulci lacrimales maxillae .............................................118
4.2.3.4 Zur Klinik des Sulcus lacrimalis maxillae ...............................................................125
4.2.3.5 Ausgewählte Fallbeispiele........................................................................................125
4.2.3.6 Zusammenstellung der morphologischen Veränderungen des Sulcus lacrimalis
maxillae.....................................................................................................................128
4.2.4 Nasennebenhöhlen .......................................................................................................133
4.2.4.1 Anatomische Grundlagen.........................................................................................133
4.2.4.2 Veränderte Nasennebenhöhlen.................................................................................137
4.2.4.3 Individuen mit veränderten Nasennebenhöhlen .......................................................159
4.2.4.4 Zur Klinik der Nasennebenhöhlen ...........................................................................171
4.2.4.5 Ausgewählte Fallbeispiele........................................................................................174
4.2.4.6 Zusammenstellung der morphologischen Veränderungen in den
Nasennebenhöhlen.....................................................................................................186
4.3 Pneumatische Räume des Schläfenbeins..............................................................................202
4.3.1 Mittelohr.......................................................................................................................202
4.3.1.1 Anatomische Grundlagen.........................................................................................202
4.3.1.2 Betroffene Mittelohren.............................................................................................204
4.3.1.3 Individuen mit betroffenen Mittelohren...................................................................214
4.3.1.4 Zur Klinik des Mittelohres .......................................................................................220
4.3.1.5 Ausgewählte Fallbeispiele........................................................................................221
4.3.1.6 Zusammenstellung der morphologischen Veränderungen der Mittelohren .............222
4.3.2 Warzenfortsatz .............................................................................................................225
4.3.2.1 Anatomische Grundlagen.........................................................................................225
4.3.2.2 Betroffene Warzenfortsätze......................................................................................226
4.3.2.3 Individuen mit betroffenen Warzenfortsätzen ..........................................................236
4.3.2.4 Zur Klinik des Warzenfortsatzes..............................................................................243
4.3.2.5 Ausgewählte Fallbeispiele........................................................................................244
4.3.2.6 Zusammenstellung der morphologischen Veränderungen der Warzenfortsätze......248
4.4 Rippen ..................................................................................................................................253
4.4.1 Allgemeine Anatomie des Brustkorbes........................................................................253
4.4.2 Zusammenstellung morphologischer Veränderungen an den Rippen..........................264
4.4.2.1 Impressionen ............................................................................................................265
4.4.2.2 Neubildungen ...........................................................................................................278
4.4.2.3 Differentialdiagnostisch relevante Veränderungen ..................................................314
4.4.2.4 Überblick über die häufigsten Veränderungen an den Rippen.................................339
4.4.2.5 Gruppen von intravitalen Veränderungen an den Rippen ........................................347
4.4.3 Veränderte Rippen........................................................................................................353
4.4.3.1 Krankheitshäufigkeiten der Rippen I bis XII ...........................................................366
4.4.3.2 Durchschnittliche Anzahl kranker Rippen ...............................................................401
4.4.3.3 Am häufigsten erhaltene Brustkorbbereiche ............................................................410
4.4.4 Individuen mit veränderten Rippen..............................................................................413
4.4.4.1 Übersicht über pathologische Veränderungen an den Rippen .................................423
4.5 Knöcherne Strukturen der oberen und unteren Atemwege und knöcherne Strukturen, die
mögliche Komplikationen der Erkrankungen der oberen Atemwege anzeigen...................429
5 Diskussion .......................................................................................................................441
5.1 Diskussion der Alters- und Geschlechtsverteilung und der Sterblichkeit ............................441
5.2 Diskussion der Erkrankungen der oberen Atemwege ..........................................................443
5.2.1 Klinische Diskussion der oberen Atemwegserkrankungen der Erwachsenen von
Wandersleben ...............................................................................................................443
5.2.1.1 Häufigste Erkrankungen der oberen Atemwege.......................................................446
5.2.1.1.1 Sinusitiden..........................................................................................................447
5.2.1.1.2 Pansinusitis.........................................................................................................454
5.2.1.1.3 Chronische Sinusitiden und Osteome ................................................................456
5.2.1.1.4 Chronische Rhinitiden und Sinusitiden..............................................................458
5.2.1.1.5 Fortleitungen der Rhinitiden auf die vordere knöcherne Nasenöffnung und den
knöchernen Tränennasengang.............................................................................463
5.2.1.1.6 Komplikationen der Rhinitis und der Sinusitis (Rhinosinusitis) mit spezieller
Betrachtung des Mittelohres und des Warzenfortsatzes .....................................468
5.2.1.1.7 Spezifische Infektionen der oberen Atemwege mit Tuberkulose als
Schwerpunkt..........................................................................................................472
5.3 Diskussion der Erkrankungen der unteren Atemwege .........................................................476
5.3.1 Klinische Diskussion der unteren Atemwegserkrankungen der Erwachsenen von
Wandersleben ...............................................................................................................476
5.3.1.1 Erkrankungen der unteren Atemwege ......................................................................476
5.3.1.2 Krankhafte Veränderungen an den Rippen der Individuen von Wandersleben .......480
5.4 Zusammenfassende Diskussion der Erkrankungen der oberen und unteren Atemwege ......491
5.4.1 Diskussion der Erkrankungen der oberen und unteren Atemwege ..............................491
5.4.2 Diskussion der Atemwegserkrankungen der Erwachsenen von Wandersleben in
Bezug auf die Lebensumstände im Neolithikum ..........................................................495
5.4.2.1 Außenluftfaktoren ....................................................................................................497
5.4.2.1.1 Klima und Wetter ...............................................................................................497
5.4.2.1.2 Allergene............................................................................................................499
5.4.2.1.3 Zoonosen ............................................................................................................503
5.4.2.1.4 Rauch .................................................................................................................505
5.4.2.2 Innenluftfaktoren ......................................................................................................507
5.4.2.2.1 Rauch .................................................................................................................507
5.4.2.2.2 Allergene und Zoonosen ....................................................................................510
5.4.2.2.3 Natürliche Radioaktivität ...................................................................................514
5.4.2.2.4 Ernährungszustand .............................................................................................515
5.4.2.3 Erkrankungen ...........................................................................................................520
5.4.2.4 Nutzung der Zähne als Werkzeug ............................................................................525
5.4.3 Diskussion der Atemwegserkrankungen der Kinder von Wandersleben .....................526
5.4.4 Zusammenfassender Überblick über Atemwegserkrankungen und deren
möglichen Entstehungsursachen in Wandersleben .......................................................528
5.4.5 Vergleich der Atemwegserkrankungen der erwachsenen Individuen von
Wandersleben mit anderen Populationen......................................................................530
5.4.5.1 Vergleich der unspezifischen Erkrankungen der Atemwege ...................................532
5.4.5.2 Vergleich der spezifischen Erkrankungen der unteren Atemwege ..........................538
5.4.6 Abschließende Zusammenfassung für Wandersleben..................................................540
6 Zusammenfassung........................................................................................................... 542
7 Literaturverzeichnis......................................................................................................... 546
Befundkatalog der untersuchten Cranien und Costae aus der Skeletserie Wandersleben
(geordnet nach Fundnummern)
Im Katalog angewandte Methoden zur Befunderhebung und Erklärungen zum Katalog ....... I
Literatur ................................................................................................................................. X
Curriculum Vitae
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Srovnání zátiší typu vanitas v italském, francouzském a holandském prostředí 17. století a dohledání případných vlivů na českou školu / A Comparison of Vanitas Still Life in Italian, French and Dutch 17th Century Environment and Searching for Influences on Czech SchoolPourová, Kristina January 2020 (has links)
My diploma thesis concerns itself with the depiction of the still life, in particular the type known as "vanitas", symbolizing the transience of human life. I focus on several artists working in Italy, France and Netherlands during the 17th century - Salvator Rosa, Simon Renard de Saint Andre, Jan Davidsz de Heem, and Nicolaes van Verendael - and explore their influence on the Czech artists Johann Adalbert Angermeyer, Jan Kaspar Hirschely, and Vaclav Vavrinec Reiner, who dealt with the same topic.
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Chirurgie endoscopique des sinus pour le traitement de la rhinosinusite chronique : évaluation des résultats opératoires et définition du succèsSaydy, Nadim 04 1900 (has links)
La rhinosinusite chronique (RSC) est une maladie avec une haute prévalence au Canada et des impacts économiques et individuels importants. Une des options thérapeutiques dans l’algorithme complexe de traitement est la chirurgie endoscopique des sinus (CES), qui est préconisée chez les patients qui ont une réponse insatisfaisante à la thérapie médicale. Le présent mémoire porte sur les critères minimaux nécessaires à l’atteinte du succès en matière de CES. Dans un premier temps, une consultation d’experts en RSC Canadiens provenant de 12 institutions nous a permis d’offrir des définitions du succès acceptable ainsi que du succès optimal du point de vue des prestataires de santé. Dans un deuxième temps, une étude auprès de 22 patients souffrant de RSC nous a permis d’identifier les thèmes importants qui doivent guider le processus décisionnel collaboratif. La première étude a permis de conclure qu’une définition du succès post-opératoire en CES se doit de comporter 2 composantes : un aspect objectif (endoscopie nasale) et un aspect subjectif (test d’issues mesurées par le patient ou questionnaire spécifique). Selon les experts, pour parler de succès optimal il faut une résolution complète des symptômes ainsi qu’un résultat endoscopique parfait. La deuxième étude a permis de démontrer que les patients accordent beaucoup plus d’importance à la résolution du symptôme cardinal qui les a amenés à consulter. Cette dernière étude a également permis une exploration plus large des objectifs et attentes, ainsi que de l’expérience patient en ce qui a trait à la RSC et à la CES.
En conclusion, l’évaluation des aspects subjectifs devrait être l’aspect le plus important que les cliniciens évaluent pour parler de succès. Une évaluation de la cavité nasale et des sinus devrait complémenter cette évaluation environ 3 mois après la chirurgie. Ce mémoire inclus des algorithmes pour aider les cliniciens dans l’évaluation du succès opératoire après une CES. / Chronic rhinosinusitis (CRS) is a prevalent, complex disease with important economic and individual impacts. Functional endoscopic sinus surgery (FESS) is widely used treatment for CRS, which is considered in patients with an unsatisfactory response to maximal medical therapy. This thesis examines the different ways clinicians may obtain feedback with regards to post-operative success and aims to offer definitions of acceptable success and optimal success. First, a consultation of Canadian experts in CRS from 12 institutions permitted us to construct definitions of acceptable and optimal success from healthcare providers’ viewpoint. Second, a study in collaboration with 22 patients suffering from CRS allowed us to identify key themes which will facilitate the inclusion of primary stakeholders in shared decision-making. The first study allowed us to conclude that a definition of postoperative success must be based on 2 components: an objective aspect (nasal endoscopy) and a subjective aspect (patient-reported outcome measure or specific questionnaire). According to experts, optimal success requires a complete resolution of symptoms as well as a perfect endoscopic result. With the second study, we demonstrated that patients tend to focus on the resolution of their cardinal symptom. This last study also allowed us to widely explore patients’ objectives and expectations, as well as their experience with CRS and FESS.
In conclusion, subjective aspects should be the most important determinants of success after FESS. In addition, an evaluation of the nasal cavity and sinuses should complement the subjective evaluation approximately 3 months after surgery. This thesis includes algorithms to aid clinicians in evaluating the outcome of FESS for patients with CRS.
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Biology and conservation of the Cape (South African) fur seal Arctocephalus pusillus pusillus (Pinnipedia: Otariidae) from the Eastern Cape Coast of South AfricaStewardson, Carolyn Louise, carolyn.stewardson@anu.edu.au January 2002 (has links)
[For the Abstract, please see the PDF files below, namely "front.pdf"] CONTENTS. Chapter 1 Introduction. Chapter 2 Gross and microscopic visceral anatomy of the male Cape fur seal with reference to organ size and growth. Chapter 3 Age determination and growth in the male Cape fur seal: part one, external body. Chapter 4 Age determination and growth in the male Cape fur seal: part two, skull. Chapter 5 Age determination and growth in the male Cape fur seal: part three, baculum. Chapter 6 Suture age as an indicator of physiological age in the male Cape fur seal. Chapter 7 Sexual dimorphism in the adult Cape fur seal: standard body length and skull morphology. Chapter 8 Reproduction in the male Cape fur seal: age at puberty and annual cycle of the testis. Chapter 9 Diet and foraging behaviour of the Cape fur seal. Chapter 10(a) The Impact of the fur seal industry on the distribution and abundance of Cape fur seals. Chapter 10(b) South African Airforce wildlife rescue: Cape fur seal pups washed from Black Rocks, Algoa Bay, during heavy seas, December 1976. Chapter 11(a) Operational interactions between Cape fur seals and fisheries: part one, trawl fishing. Chapter 11(b) Operational interactions between Cape fur seals and fisheries: part two, squid jigging and line fishing. Chapter 11(c) Operational interactions between Cape fur seals and fisheries: part three, entanglement in man-made debris. Chapter 12 Concentrations of heavy metals (Cd, Cu, Pb, Ni & Zn) and organochlorine contaminants (PCBs, DDT, DDE & DDD) in the blubber of Cape fur seals. Chapter 13 Endoparasites of the Cape fur seal. Chapter 14(a) Preliminary investigations of shark predation on Cape fur seals. Chapter 14(b) Aggressive behaviour of an adult male Cape fur seal towards a great white shark Carcharodon carcharias. Chapter 15 Conclusions and future directions.
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MECHANICAL BEHAVIORS OF BIOMATERIALS OVER A WIDE RANGE OF LOADING RATESXuedong Zhai (8102429) 10 December 2019 (has links)
<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>
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