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Baker, David Alexander. "A technique for controlled compliant drilling of bone applied to the stapedotomy procedure." Thesis, University of Bristol, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266989.
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LeMoine, Geneviève M. "Use wear analysis on bone and antler tools of Mackensie Inuit /." Oxford : BAR, 1997. http://catalogue.bnf.fr/ark:/12148/cb370277200.
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Griffitts, Janet. "Bone Tools and Technological Choice: Change and Stability on the Northern Plains." Diss., The University of Arizona, 2006. http://hdl.handle.net/10150/195929.
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This study examines decision making concerning tool use and rawmaterial choice through the analysis of bone technology from five sites from the MiddleMissouri subarea of the Northern Plains of North America. The research methods employed include high power optical microwear analysis, experimental replication,and the study of modern bone tool use. At the time of contact with Europeans andEuroamericans, the Mandan, Hidatsa, and Arikara lived in semi sedentary villages along the Missouri River where they practiced a mixed economy centered on both agriculture and bison hunting. The villagers were central in indigenous trade networks and later in the international fur trade, as European and Euroamericans traders and explorers sought to insert themselves into the existing networks. Occasional trade goods are found as early as the seventeenth century, increasing through time as more Europeans and Euroamericans entered the area, indicating that the villagers supplied the newcomers with food, horses, and furs in exchange for those goods. They also were impacted by European diseases, increasing violence, and by accompanying changes in many aspects of their society.Post contact technological change is often modeled as a relatively simple unilinear process in which metal tools quickly replaced older technologies. Analysis of modified bone and antler from historic sites indicates the processes were more complicated. Some tool types were quickly replaced, while others persisted, and there was also variation within tool types. Rather than immediately rendering bone technology obsolete, as has been suggested, there was an initial period of experimentation as people used the new metal cutting and chopping tools to modify the older bone technology. Some tools were made by simply shaping the bone with metal rather than stone, but in other cases the new metal tools were used to create bone tools in completely new forms. Both social and functional factors influence tool choices in raw material, form, and use. This study provides a deeper understanding of many processes involved in technological change in the contact period.
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VanderKolk, Melody Lynn. "Spatial Analysis of Bone Tools at SunWatch (33My57), A Middle Fort Ancient Indian Village." Kent State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=kent1240104365.
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Bryce, Joseph A. "An Investigation of the Manufacture and Use of Bone Awls at Wolf Village (42UT273)." BYU ScholarsArchive, 2016. https://scholarsarchive.byu.edu/etd/6189.
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Wolf Village is a Fremont farming village located at the southern end of Utah Valley where Brigham Young University has conducted six field schools there and recovered 135 awl and awl fragments. The Wolf Village awls, like the awls from many Fremont sites, represent a large range of morphological variability. Because of the ubiquity and diversity of Fremont bone awls, many different approaches have been taken to organize and understand them; focusing more on morphological characteristics than interpretation. In order to better understand the life use of bone awls, experiments were conducted to replicate the manufacture and use of these tools and to create a comparative collection for diagnostic characteristics. Based on the results of analysis and comparison, the craftspeople at Wolf Village used a variety of methods to make tools for use in basket-making, leatherwork, and other activities.
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Moore, Christopher R. "PRODUCTION, EXCHANGE AND SOCIAL INTERACTION IN THE GREEN RIVER REGION OF WESTERN KENTUCKY: A MULTISCALAR APPROACH TO THE ANALYSIS OF TWO SHELL MIDDEN SITES." UKnowledge, 2011. http://uknowledge.uky.edu/gradschool_diss/130.
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The Green River region of western Kentucky has been a focus of Archaic period research since 1915. Currently, the region is playing an important role in discussions of Archaic hunter-gatherer cultural complexity. Unfortunately, many of the larger Green River sites contain several archaeological components ranging from the Early to Late Archaic periods. Understanding culture change requires that these multiple components somehow be sorted and addressed individually.
Detailed re-analyses of Works Progress Administration (WPA) era artifact collections from two archaeological sites in the Green River region – the Baker (15Mu12) and Chiggerville (15Oh1) shell middens – indicate that these sites are relatively isolated Middle and Late Archaic components, respectively. The relatively unmixed character of Baker and Chiggerville makes these sites excellent candidates for evaluating aspects of complexity during the Archaic.
After developing a theoretical basis for evaluating the relative complexity of the social organization of the Baker and Chiggerville site inhabitants on the basis of the material record they left behind, I employ detailed analyses of the bone, antler, and stone tools from these two sites to examine six microscalar aspects of complexity – technological organization, subsistence, specialization, leadership, communication networks, and exchange. These microscalar aspects of complexity all can be linked materially to the archaeological record of the Green River region and can be evaluated as proxies for changes in social organization among the hunter-gatherers who inhabited this region during the Middle and Late Archaic periods. Although the Baker assemblage indicated greater complexity in communication networks and certain proxies for leadership and technological organization, most indicators suggest that the Chiggerville site inhabitants were the more complexly organized group and were in the process of developing a tribal-like social formation. This research, therefore, tentatively supports the hypothesis of increasing complexity through time during the Archaic. However, marked differences in the technological strategies utilized by the Baker and Chiggerville site inhabitants indicates these groups may not have been historically related, thereby violating one of the primary assumptions of the project. If this alternative hypothesis is confirmed through additional research, then no conclusions concerning change through time can be derived from this study.
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O'neal, Lori L. "What’s in Your Toolbox? Examining Tool Choices at Two Middle and Late Woodland-Period Sites on Florida’s Central Gulf Coast." Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6340.
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The examination of the tools that prehistoric people crafted for subsistence and related practices offers distinctive insights into how they lived their lives. Most often, researchers study these practices in isolation, by tool type or by material. However, by using a relational perspective, my research explores the tool assemblage as a whole including bone, stone and shell. This allows me to study the changes in tool industries in relation to one another, something that I could not accomplish by studying only one material or tool type. I use this broader approach to tool manufacture and use for the artifact assemblage from Crystal River (8CI1) and Roberts Island (8CI41), two sequential Middle and Late Woodland Period (A.D. 1-1050) archaeological sites on the central Gulf coast of Florida. The results of my research show that people made different choices, both in the type of material they used and the kind of tools they manufactured during the time they lived at these sites as subsistence practices shifted. Evidence of these trends aligns with discrete changes in strata within our excavations. The timing of depositional events and the artifacts found within each suggest people also used the sites differently through time. These trends exemplify the role of crafting tools in the way people maintain connections with their mutable social and physical world.
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Tolmie, Clare. "Animals for food, animals for tools: fauna as a source of raw material at Abri Cellier, Dordogne, and the Grotte du Renne, Arcy-sur-Cure." Diss., University of Iowa, 2013. https://ir.uiowa.edu/etd/2647.
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The adoption of bone tool technology in the Early Upper Palaeolithic of Europe by Neanderthals and anatomically modern humans has been the focus of considerable debate. In particular this debate has focused on the origins of the technology and the possible implications for the extinction of Neanderthals. This dissertation examines the context of element selection for use as raw material to produce bone tools, related to prey species in the Châtelperronian of the Grotte du Renne, Arcy-sur Cure and the Aurignacian of Abri Cellier, Dordogne.
Current research indicates that there was little difference in the subsistence organization of Neanderthals and modern humans. As a more nuanced view of Neanderthal behavior emerges from recent studies, it is becoming apparent that differences between the two hominins are a matter of degree rather than absolute difference. The faunal analysis of the two assemblages in this dissertation found that both Neanderthals and modern humans were pursuing a foraging strategy to obtain prime age herbivores for food. Locally available taxa were taken. Carcasses were processed for meat, marrow and fat.
Both assemblages show a preference for non-marrow bearing long bones or long bone shaft fragments to make tools. The raw material was chosen with reference to the mechanical properties of the bones, which exhibit elasticity necessary for use as awls or hide scrapers. Raw material was a by-product of the larger subsistence strategy. There is a difference in the use of antler. This is not used by Neanderthals. In the Aurignacian, it appears that the amount of antler represented by the points and tools at Abri Cellier could be obtained as part of a general foraging strategy.
The appearance of bone tools in the Early Upper Palaeolithic has been argued as evidence for `modern' behavior. It might be more profitable to view the adoption of this new technology as a response by two different but related populations to particular ecological problems. It could be argued that the archaeological visibility of bone tools reflects an increasing investment in the production of more effective clothing by both Neanderthals and modern humans.
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Ramme, Austin Jedidiah. "High throughput patient-specific orthopaedic analysis: development of interactive tools and application to graft placement in anterior cruciate ligament reconstruction." Diss., University of Iowa, 2012. https://ir.uiowa.edu/etd/2966.
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Medical imaging technologies have allowed for in vivo evaluation of the human musculoskeletal system. With advances in both medical imaging and computing, patient-specific model development of anatomic structures is becoming a reality. Three-dimensional surface models are useful for patient-specific measurements and finite element studies. Orthopaedics is closely tied to engineering in the analysis of injury mechanisms, design of implantable medical devices, and potentially in the prediction of injury. However, a disconnection exists between medical imaging and orthopaedic analysis; whereby, the ability to generate three-dimensional models from an imaging dataset is difficult, which has restricted its application to large patient populations. We have compiled image processing, image segmentation, and surface generation tools in a single software package catered specifically to image-based orthopaedic analysis. We have also optimized an automated segmentation technique to allow for high-throughput bone segmentation and developed algorithms that help to automate the cumbersome process of mesh generation in finite element analysis. We apply these tools to evaluate graft placement in anterior cruciate ligament reconstruction in a multicenter study that aims to improve the patient outcomes of those that undergo this procedure.
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Fuld, Kristen Ann. "The Technological Role of Bone and Antler Artifacts on the Lower Columbia: A Comparison of Two Contact Period Sites." PDXScholar, 2011. https://pdxscholar.library.pdx.edu/open_access_etds/580.
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This thesis explore the technological role of bone and antler artifacts from two contact period southern Northwest coast archaeological sites, the Cathlapotle site (45CL1) and the Meier site (35CO5). Technological measures of sedentism are based on lithics, and predict residential sedentism promotes technological expediency in hunter-gatherers (Parry and Kelley 1987). Cathlapotle and Meier lithic assemblages consist of expedient and opportunistic assemblages and raw material stockpiles, with the exception of highly curated projectile points and endscrapers (Hamilton 1994). The expectation that residential sedentism promotes technological expediency in hunter-gatherers was tested on the Cathlapotle and Meier bone and antler artifact assemblages in two ways. First, curation and expediency were recorded for each artifact by measuring level of energy investment in manufacture or degree of working. Second, a spatial analysis was used to explore methods of artifact storage and disposal. Results revealed both Cathlapotle and Meier osseous assemblages are highly curated, except for expedient awls and flakers. Specifically, artifact classes related to subsistence procurement, modification including woodworking, and ornamentation were highly curated. Both sites contain stockpiles of unmodified bone and antler. The spatial analysis showed level of curation did not affect artifact disposal method. Despite this, some patterns were evident. At Cathlapotle, curated procurement and modification artifacts, expedient awls as well as worked fragments were concentrated outside the houses, specifically in Sheet Midden. Broken modification artifacts, ornaments, and detritus were randomly distributed. At the Meier site, curated procurement and modification artifacts, as well as expedient awls were randomly distributed. Broken modification artifacts, detritus and worked fragments were concentrated outside the houses. Ornaments were concentrated in the northern segment (elite area) of the house. There were also significantly more curated complete tools recovered from the cellar facility, while significantly fewer curated complete tools were recovered from the midden facility at Meier. In this thesis, the effects of contact on osseous assemblages were examined. It is an assumption of North American archaeologists that European-introduced metals replace and/or change the character of traditional technologies such as lithic and osseous technologies. Few quantitative studies comparing pre and postcontact artifact assemblages exist (Bamforth 1993, Cobb 2003). In some parts of northeast North America, European contact is followed by a proliferation of osseous tool working, and over time osseous artifacts drop out of the archaeological record (Snow 1995, 1996). Cathlapotle and Meier were occupied from AD 1400 to AD 1830, spanning European contact. People at Cathlapotle were in direct contact with Europeans and Euro-Americans since 1792 (Boyd 2011). Previously, it was assumed Cathlapotle was more involved in the fur trade than Meier, because Cathlapotle was mentioned several times in ethnohistoric accounts, while Meier was never mentioned. Also Cathlapotle contains far more historic trade items than Meier (Ames 2011). The assumption that European-introduced metals replace and/or change the character of traditional technologies was tested on the Cathlapotle and Meier assemblages by comparing artifact frequency, density, and assemblage diversity of pre and postcontact assemblages. Results show contact is reflected in the osseous assemblages at both Cathlapotle and Meier. Contact is evident, but is reflected in different ways. At Cathlapotle, artifact frequencies, densities, and assemblage diversity decrease postcontact. In contrast at Meier, artifact frequencies and densities increase postcontact, with some artifact classes tripling or quadrupling in frequency. The introduction of metal could have enabled people to work osseous materials faster and easier, decreasing manufacture time, cost, and overall energy investment. The gain in efficiency promoted the proliferation of bone working and an abundance of osseous tools at the Meier site. These results encourage a reevaluation of Meier's role in the fur trade. At Cathlapotle, metal objects may have replaced osseous tools resulting in the decline of bone and antler working and/or activity patterns shifted away from activities requiring osseous tools. The results of this thesis deviate from typical Northwest Coast bone and antler assemblages, challenge technological models of sedentism that are based on lithics, and contradict assumptions of Lower Columbians involvement in the fur trade.
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Baumann, Malvina. "À l'ombre des feuilles de laurier : les équipements osseux solutréens du sud-ouest de la France : apports et limites des collections anciennes." Thesis, Paris 1, 2014. http://www.theses.fr/2014PA010573.
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Le Solutréen est une chronoculture du Paléolithique supérieur identifiée en France et dans la péninsule ibérique entre 25000 et 23000 cal BP. Son industrie lithique est immédiatement reconnaissable à ses pointes foliacées, souvent retouchées par pression. Son industrie osseuse en revanche, est considérée comme peu spécifique. En réalité, peu de chose étaient jusque là connues de l’importance, de la composition ou de l’évolution de cette industrie, encore moins des procédés de fabrication mis en œuvre ou des activités auxquelles elle était liée.Afin d’en dresser un premier bilan nous avons étudié l’équipement en os, bois de cervidé et ivoire de 4 grands gisements de référence du sud-ouest de la France. L’étude révèle que l’industrie osseuse solutréenne se compose surtout d’outils peu transformés. Parmi eux, les compresseurs, utilisés pour réaliser la retouche par pression, renvoient directement aux productions des pointes lithiques foliacées et deviennent de ce fait un marqueur de la période. Les débitages du bois de renne sont réalisés par fracturation, une modalité considérée jusque là comme spécifiquement Badegoulienne. Son utilisation au Solutréen permet de relancer la question d’une parenté entre les deux chronocultures.Nous avons eu recours à l’expérimentation et mis l’accent sur les traces techniques et fonctionnelles pour palier l’absence de référentiels relatifs à ce mode de production et à ce type d’objet. Dans tous les cas, nos résultats ont été contraints par la nature des collections archéologiques, toutes issues de fouilles menées entre la fin du XIXe et le début du XXe siècle. La révision critique de leur composition nous a conduits à redéfinir les limites du corpus solutréen. Si l’industrie osseuse solutréenne possède de réelles particularités, l’étendue de sa diversité reste à explorerThe Solutrean culture is a stage of the French and Spanish Upper Paleolithic, from between 25000 and 23000 cal BP. Its lithic industry is immediatly recognizable thanks is leaf points often shaped by pressure. Inversely, its bone industry is seen a being poorly specific. Actually little was know about the extent, the composition and the evolution of the Solutrean bone industry and even less about tools making and fuction.In order to take a first stock we have studied bone, antler and ivory equipment from 4 famous Solutrean settlements of South Western France. Our study shows that the Solutrean bone industry mainly consist of little shaped tools. Among them, pressure flaking tools are directly related to the production of the lithic leaf points and therefore can be seen as a cultural marker. Blank production is done by fracturing, a process which was regarded as being specifically Badegoulian. This allows to restart the debate about the relationship between the two cultures.Through an experimental approach we put the emphasis on the technical and the functional traces for palliating the lack of frame of reference related to this mode of production and this kind of object. In all cases, our results were compelled by the makeup of the archeological collections, resulting from excavations of the end of the XIXth and the beginning of the XXth century. A critical review of their composition led us to reconsider the perimeter of the Solutrea assemblage. If he Solutrean bone industry has very distinctve features, the extend of its diversity remains to be explored
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Backwell, Lucinda Ruth. "Early hominid bone tool industries." Bordeaux 1, 2003. http://www.theses.fr/2003BOR12962.
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La présente recherche porte sur l'utilisation d'outils en os par les hominidés qui vivaient il y a un à deux millions d'années. Elle se propose, en caractérisant les modifications produites par des agents humains et non humains, d'établir des critères diagnostiques pour l'identification d'outils en os n'ayant subi qu'une modification minimale et d'appliquer ces critères aux pièces osseuses de Swartkrans, Sterkfontein et Olduvai Gorge, interprétées dans le passée comme des outils en os. Pour accroître la gamme des critères diagnostiques disponibles nous avons mené plusieurs expérimentations. Des nouvelles techniques d'analyse ont été également élaborées. Elles ont permis de quantifier l'état de surface sur les outils potentiels. Une vaste gamme de variables taphonomiques et morphométriques ont été enregistrées. Nos résultats indiquent que les outils en os utilisés par des premiers hominidés reflêtent deux traditions culturelles distinctes et contemporaines. Les outilsidentifiés dans la collection de Olduvai sont réalisés à partir d'os longs à l'état frais appartenant à des mammifères de grande à très grande taille. Plus rarement des os entiers du tarse ou du genoux sont utilisés comme percuteurs. Pour modifier ces pièces les hominidés appliquent à l'os une gestuelle proche de celle qu'ils utilisent pour tailler la pierre. En considerdant le nombre de pièces découvertes par rapport à celui des pièces lithiques, la taille de l'os ne semble par représenter chez les hominidés de Olduvai une activité systématique et il est possible qu'elle se soit cantonnée au traitement des carcasses de grands mammifères. Les outils des sites sud-africains, par contre, sont fabriqués presque exclusivement à partir de fragments de diaphyse d'os longs et de chevilles osseuses de bovidés de petites à moyenne taille, sont occasionnellement façonnés par abrasion et leur fonction est de servir comme outils à fouir. Dans les deux régions, l'apparition d'outils en os ne coi͏̈ncide pas avec l'apparition du genre Homo, et la période qui voit d'adoption de ces techniques se termine avec la disparition d'Australopitecus robustus. Cela suggère, en considérant la quasi-absence d'outils en os à l'Achéuléen et au début du Middle Stone Age, que les premières industries en os ne représentent pas, comme cela a été proposé autrefois, la première étape d'un processus de sophistication progressive, associée à l'apparition de notre genre, mais plutôt le résultat d'adaptations ponctuelles developpées par certaines de nos prédecesseurs.
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Torres, Nogueira Luisa Maria. "Les lésions osseuses tranchantes (par scies) et tranchantes contondantes : analyse des mécanismes lésionnels et des instruments à l'origine de ces lésions." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0272/document.
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Ce travail expérimental s’est intéressé aux lésions osseuses produites par des scies et par une hachette, sur des échantillons humains et animaux. En ce qui concerne les scies, 170 faux départs ont été étudiés au stéréomicroscope en utilisant cinq scies différentes. Les scies universelles se comportent comme les scies à tronçonner, du fait de l’inclinaison vers l’arrière de chaque dent. La largeur minimum du faux départ permet de classer les lésions selon les catégories de Symes. Les profils convexes indiquent l’utilisation d’une scie universelle ou d’une scie à tronçonner. Les profils concaves sont beaucoup plus variés, et indiquent l’utilisation d’une scie à refendre. La forme des murs permet de déterminer le type d’avoyage sauf quand ils sont droits ou difficiles à analyser. Parmi les critères secondaires, l’aspect des stries au fond de la lésion s’est révélé de grande importance pour identifier le type d’avoyage. En ce qui concerne la hachette, nous avons utilisé un protocole standardisé produisant des lésions osseuses de petites dimensions. Le stéréomicroscope a constaté le caractère vertical des stries, qui s’explique par le mouvement vertical effectué par l’instrument au moment de l’impact. Le microscope électronique à balayage a permis de décrire parfaitement les lésions, de comprendre la surélévation des berges (« uprising ») et l’effet exercé à distance (« lateral pushing back »). La présence du latéral pushing back et de stries verticales permet d’affirmer que les lésions osseuses ont été produites par un instrument tranchant contondant. Ces caractères se pérennisent même après carbonisationIn this experimental work bone lesions produced by saws and a hatchet on human and animal samples were analyzed. With regard to the saws, 170 experimental false starts lesions were studied under stereomicroscope produced by five different saws. Universal saws behave like crosscut saws, because each tooth displays a tilt backwards. The minimum width of the kerf makes it possible to classify bone lesions according to Symes’ categories. Convex profiles indicate the use of a universal or crosscut saw. Concave profiles vary a great deal and indicate the use of a rip saw. The shape of the walls allows for determining the type of set except when they are straight or difficult to analyze. Among the secondary criteria, the appearance of the striae on the kerf floor is able to point the type of set. For the study of bone lesions by a hatchet a standardized device was used to produce small bone lesions. The stereomicroscope was able to observe the vertical striae explained by the vertical movement of the instrument at the time of impact. The scanning electron microscope allowed for a detailed analysis of bone lesions and made it possible to understand the uprising and the lateral pushing back. The presence of a lateral pushing back and of vertical striae is sufficient to determine that the bone lesions were achieved by a sharp blunt instrument. These characters are visible even after carbonization
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Ferraro, Joseph Vincent. "Broken bones and shattered stones on the foraging ecology of Oldowan hominins /." Diss., Restricted to subscribing institutions, 2007. http://proquest.umi.com/pqdweb?did=1568044151&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.
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Maggiano, Corey. "CONFOCAL LASER SCANNING MICROSCOPY AS A TOOL FOR THE INVESTIGATION OF TETRACYCLINE FLUORESCENCE IN ARCHAEOLOGICALHUMAN BONE." Master's thesis, University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2752.
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Fluorochromes such as tetracycline have been used to label bone for histomorphometric analysis, measuring bone formation, growth, maintenance, and pathology. More recently, similar fluorescence has been observed in ancient human bone. Attributed to tetracycline (TC) exposure, this phenomenon could affect various aspects of health during life and/or preservation of remains postmortem. Standard epifluorescence microscopy is the most common tool employed in the analysis of these labels. Though valuable, this technique is limited by its inability to penetrate bone three-dimensionally and its inclusion of out-of-focus light, possibly disrupting accurate analysis. Confocal Laser Scanning Microscopy (CLSM) has been demonstrated as a valuable tool for three-dimensional histology. Its application to the study of compact bone fluorescence has been lacking, especially in archaeological and forensic sciences. In the following two papers, modern TC-controlled bone is compared to well preserved archaeological bone recovered from the Dakhleh Oasis, Egypt, using both standard wide-field and more modern confocal techniques for imaging and analysis. Spectral analysis via CLSM shows that both modern and ancient fluorescent labels in bone share the exact same fluorescence emission peak at 525 nm. Differences in the shape of the spectral curve and photobleaching characteristics are discussed. In addition, CLSM's high-resolution two- and three-dimensional imaging capabilities (in polarized light, scattered light, and fluorescence light) are found to increase the flexibility and creativity of investigations into the occurrence of tetracycline labels in archaeological bone and could have added benefits for modern medical and anatomical experimentation.M.S.
Department of Biology
Arts and Sciences
Biology
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Findlay, Caroline M. "Image analysis tool for the characterisation of bone turnover in the appendicular skeleton." Thesis, University of Glasgow, 2012. http://theses.gla.ac.uk/3657/.
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Osteoporosis is a disease characterised by reduced bone mass and altered microarchitecture leading to an increased risk of fracture. The consequences of osteoporosis include reduced quality of life and pain, associated with fractures. Its financial burden on health services are significant. Characterisation of osteoporosis using imaging techniques is therefore important. Peripheral Quantitative Computed Tomography (pQCT) is a cross-sectional imaging method which is used to scan bones in the appendicular skeleton. pQCT imaging may be particularly useful in clinical groups where changes in bone mineral density (BMD) and structure are known to occur in the limbs. Two such groups are patients following spinal cord injury (SCI) or anterior cruciate ligament (ACL) injury. Aims. This project aimed to develop analysis techniques to characterise bone in pQCT images. Their purpose was to describe localised changes within pQCT images of the bone, as opposed to the standard global measurements. Methods. Fully automated segmentation and registration software was developed and tested followed by two independent processing algorithms. The first generates spatial maps to characterise local changes in BMD. This is achieved using both quadrant analysis software and a voxel-based approach, the latter comparing pairs of images and generating a voxel-by-voxel ΔBMD map of changes in BMD. The second processing algorithm uses morphological granulometries to investigate the bone microarchitecture. Results. Evaluation of these image analysis methods was carried out using two clinical studies. The first investigates acute longitudinal changes in the distal tibia (DT) and distal femur (DF) post-motor-complete-SCI using pQCT. Images from 15 subjects (13M, 2F) with a mean age of 36y±19y, were acquired at 4-monthly intervals during the first year post-injury. The second comprises of ACL injury subjects, with imaging of the injured and contralateral proximal tibia (PT) and distal femur before (n=19, 18M 1F, 30y±9y of age) and after (n=8, 8M 0F, 31y±9y of age) surgical ACL reconstruction. The software developed to automatically segment bone from surrounding structures was successful: 98% success rate for epiphyseal tibial regions, 67% success rate for the distal femur. Registration of images was then performed and the spatial analysis methods to automatically produce quadrants of trabecular bone were applied, displaying individual results graphically. The voxel based analysis method was developed, tested and applied to produce ΔBMD maps, utilising statistical inference and corrections for multiple comparisons using a false-discovery rate technique. These maps characterised localised changes in BMD between pairs of both longitudinal and contralateral images. Software was also developed to apply morphological granulometries to pQCT images, calculating global and local pattern spectrum moments. On application of the analysis methods to the longitudinal SCI images, the BMD and microarchitecture findings were observed to be disparate amongst subjects, with large variations in bone characteristics both globally and regionally. The quadrant and voxel based analysis methods provided information on longitudinal regional changes in each subject, indicating individual patterns of change. Structural analysis of bone microarchitecture using granulometries was demonstrated to have potential as a useful adjunct to BMD in identifying SCI subjects more susceptible to rapid bone loss. The analysis methods were also successfully applied to the ACL injury subjects. Following segmentation and registration, the total and trabecular BMD in the injured knee was observed to be significantly lower than that of the contralateral control knee pre-operatively for both the PT and DF (p<0.05). Post-operatively the total and trabecular BMD in the injured DF remained significantly low (p<0.05), however the PT demonstrated significantly lower BMD in the injured leg for the trabecular bone only (p<0.05). Reduced BMD in the PT post-operatively in humans is a novel observation, and indicates a benefit afforded by segmenting trabecular from cortical bone. Regional analysis using quadrants indicated some anatomical variation in bone loss within the injured limb, although it is acknowledged that these are preliminary findings which would require to be confirmed in larger studies. The voxel ΔBMD maps generally indicated global losses across the bones of the ACL injured leg both pre-operatively and post-operatively. No consistent patterns were obtained in the ΔBMD maps for these subjects, suggesting individual patterns of response to ACL injury. The structural information provided by granulometric analysis was limited for the ACL study. Conclusions. Automated software has been developed to characterise bone in pQCT images of the appendicular skeleton. It has been successfully applied to two clinical studies, facilitating localised changes in bone density to be demonstrated and descriptions of microarchitecture to be provided. The SCI subjects appear to have individualistic responses to injury, with a wide range of changes in bone density and microarchitecture observed. ACL injury patients all lost bone mass, but patterns of change were variable. The analysis methods developed to permit characterisation of bones in individual subjects, are proposed to be of value in both clinical and research domains exploring bone mass and microarchitecture, with the ultimate goals being the prediction of fracture risk and tailoring therapy for the individual.
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Dewbury, Adam Gordon. "Stones and bones an actualistic approach to understanding cutmark frequency variation /." Diss., Online access via UMI:, 2009.
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Fagg, Rajni. "Evaluation of in vitro bone marrow culture as a tool for assessing mechanisms of haematotoxicity." Thesis, University of Hertfordshire, 2008. http://hdl.handle.net/2299/1980.
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Dose limiting haematotoxicity has been associated with a range of therapeutic agents used for the treatment of a number of different conditions. Haematotoxicity is usually assessed as part of the preclinical safety studies in experimental animals, where changes in peripheral blood cell numbers and bone marrow cellularity are determined at the end of the study. Often no information on the mechanism of the haematotoxicity is revealed. This thesis demonstrates how in vitro bone marrow cultures can be utilized to assist in the assessment of haematotoxicity by two different approaches; firstly, in vitro bone marrow cultures can be used to assess the haematopoietic lineage specificity of vincristine sulphate, vinblastine sulphate, hydroxyurea and anagrelide hydrochloride using clonogenic cultures, enabling ranking of these compounds according to their haematotoxicity. Secondly, using in vitro assays only, elucidate the mechanism(s) of the megakaryocytic lineage specific inhibition of anagrelide hydrochloride. To this end both clonogenic cultures and LTBMC offer the ability to elucidate mechanisms of action on multipotent stem cells, lineage specific cells and effects on the bone marrow microenvironment following single and repeated administration. In addition, the combination of cell identification techniques flow cytometry and light microscopy was shown to provide a more detailed understanding of the different cell populations within the non-adherent cell layer. In vivo AN reduces platelet counts only, however, the mechanism of the megakaryocyte specific toxicity by AN is not understood. In these studies, the mechanism (s) of the megakaryocytic lineage haematotoxicity of AN was examined using the established human clonogenic and LTBMC. The action of AN was shown to be focused at a late stage in megakaryocyte (Mk) colony development. Ranking the potential mechanisms of action of AN by concentration at which they were noted, the inability to organize the microtubules appears to be secondary to 1) alteration in cell cycling, 2) surface receptor expression and 3) inhibition in achieving high (greater than 8N) ploidy number. However, identification of the primary mechanism based solely on concentration seems to be very crude and most probably reflects a limitation of in vitro systems. The inhibition of platelet production by AN is most likely a result from a combination of mechanisms; inhibition of cell cycling, disruption in the expression of cell surface receptors, inhibition of the ability of the cells to increase ploidy number and an associated inability to organize microtubules leading to a reduction in platelet release. This work also demonstrated the importance of the selection of the source of bone marrow used in the cultures. The concentration at which 50 percent of Mk colony growth was inhibited (IC50) by AN for murine cells was markedly (46 fold) different (88.6μM) compared to the IC50 with human cord blood (hCB) (1.92μM). This disparity is indicative of differences in species sensitivity possibly related to AN having a greater affinity towards the human c-mpl chrombopoietin (TPO) receptor than the equivalent murine receptor as suggested by McCarty et al (2006). This work highlights the utility of in vitro bone marrow cultures as a tool for investigating the lineage specific haematotoxicity by evaluating compounds used in the treatment of ET. In addition in vitro haematopoietic cultures can successfully be used as a tool to investigate potential mechanism(s) of haematotoxicity as demonstrated herein by providing an insight to mechanism of platelet count reduction by AN.
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Fingerhut, Raetz Doria Lee. "Bone tool assemblages as an aid to shell mound site typologies on the Northwest coast." PDXScholar, 1989. https://pdxscholar.library.pdx.edu/open_access_etds/3929.
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Fifteen bone tool assemblages from shell midden sites were compared. Three of these are unpublished sites from Prince Rupert Harbor. They were grouped using cluster analysis. Inter and intragroup variation in bone tool assemblage structure was analyzed. One of the objectives of this study was to generate hypotheses about the function of the unpublished sites by comparing their bone tool assemblages with those from sites which are better understood by looking for underlying patterns in the bone tool assemblages. Other objectives were to test the utility of using bone tool assemblages as a diagnostic tool in analyzing sites and to test the utility of the cluster analysis procedure with this data set.
Hypotheses were developed identifying possible site usage at the three Prince Rupert Harbor sites, Boardwalk (GbTo-31), Garden Island (GbTo-23), and Grassy Bay (GbTn-1). Bone tool assemblages were shown to be a useful aid in site analysis and cluster analysis was quite useful in identifying existing patterns in these data.
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Veta, Jacob E. "Analysis and Development of a Lower Extremity Osteological Monitoring Tool Based on Vibration Data." Miami University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=miami1595879294258019.
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McAlpine, Thomas H. "A study of the beamer : a prehistoric hide processing tool." Virtual Press, 2005. http://liblink.bsu.edu/uhtbin/catkey/1313639.
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In archaeology, most studies of artifacts focus on lithics and ceramics, while bone artifacts are often neglected in our intense study of the past. This thesis takes a step in the opposite direction by focusing on a bone tool known as the beamer. This thesis tests the hypothesis that the beamer, used for processing animal hides, is only used during the Late Woodland and Mississippian time periods. If the hypothesis is supported, the beamer would be unique among bone artifacts, acting as a chronological marker similar to projectile points. The thesis also studies how the hypothesized appearance of the beamer at the beginning of the Late Woodland affected the use of lithic scrapers, another tool used for hide processing. Information gathered for this thesis was used to create a large database of Midwestern prehistoric archaeological sites. While the original hypothesis did not hold up, a new hypothesis was created based on the data.Department of Anthropology
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Denk, Eberhard. "Evaluation of ⁴¹Ca as a novel isotopic tool to assess the impact of diet on bone health /." Zürich : ETH, 2006. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=16416.
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Ito, Kouta. "Use of the osteoporosis self-assessment tool : for referring older men for bone densitometry, a decision analysis /." Access full-text from WCMC :, 2008. http://proquest.umi.com/pqdweb?did=1527840081&sid=13&Fmt=2&clientId=8424&RQT=309&VName=PQD.
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King, Maggie Marie. "The vertical jump test as a health promotion screening tool for predicting bone strength in young adults." Thesis, University of Iowa, 2016. https://ir.uiowa.edu/etd/3118.
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Osteoporosis is one of the most common diseases experienced in the older adult population. This condition is not only costly to manage and treat, particularly so when osteoporotic fractures occur, but also negatively impacts functional health and health-related quality of life for many individuals. This indicates the need for more to be done to prevent osteoporosis from developing initially. While bone mineral density (BMD) testing recommendations are in place for women aged 65 and older and men aged 70 and older to diagnose osteoporosis, there currently are no BMD testing recommendations for preventive or screening purposes in the general, healthy, adult population. One potential screening tool for bone strength is a peak vertical jump test. Peak vertical jump height can be used as a proxy for lower body muscle power, which has been identified as an influential factor in determining bone mass and geometry, both of which are critical aspects of bone strength. This study ascertained the relationship between muscle power and bone strength, as well as the capacity of a peak vertical jump test to identify young adults with below-average areal BMD (aBMD).
A total of 303 young adults (18 to 22 years, n=136 males, n=167 females) participated in these cross-sectional analyses. DXA was used to assess aBMD for total hip and femoral neck, and DXA images were used to calculate femoral neck section modulus (FN Z) values. Peripheral quantitative computed tomography (pQCT) was used to assess indices of bone strength at the tibia. Cortical bone area (CoA) and density-weighted polar section modulus strength-strain index (SSIp) were assessed at the 38% midshaft site, and bone strength index (BSI) was assessed at the 4% midshaft site. Lower body muscle power was predicted using peak vertical jump height and the Sayers et al. (1999) equation. Data were analyzed using Pearson bivariate and partial correlations to examine associations among bone strength outcomes and muscle power. Logistic regression was used to examine the probability of below-average bone strength based on muscle power. Receiver Operating Characteristic (ROC) curve analysis was used to show the tradeoff between sensitivity and specificity and to display the accuracy of a peak vertical jump test as an assessment tool for aBMD. Logistic regression indicated the odds ratio of below-average height-adjusted femoral neck aBMD decreased 5.4% for females and 3.6% for males per 50 Watts of power. ROC curve analysis showed the best sensitivity-specificity trade-off for identifying individuals with and without below-average aBMD was 5,038 Watts in males (sensitivity = 73.7%; specificity = 62.4%; AUC = 0.709, 95%CI = 0.572 - 0.847) and 3,261 Watts in females (sensitivity = 71.4%; specificity = 58.9%; AUC = 0.708, 95%CI = 0.586 - 0.829). These cut off values correspond to a vertical jump height of 54.39 cm and 36.16 cm for males and females, respectively. Taken together, the results of these analyses suggest acceptable sensitivity and specificity and moderate discriminate ability for using a measure of muscle power, assessed with a peak vertical jump test, to identify young adults with below-average aBMD.
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Blackbeard, Jill Margaret. "Reticulocyte maturation index: a prediction tool for recovery in post bone marrow and peripheral blood stem cell transplant patients." Thesis, Cape Technikon, 2002. http://hdl.handle.net/20.500.11838/1466.
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Thesis (MTech (Medical Technology))--Cape Technikon, Cape Town, 2002Erythropoietic response is the first indication of bone marrow recovery following bone marrow or peripheral blood stem cell transplantation. Manual reticulocyte counting has not only proven to be outdated but an extremely crude method of analysis, particularly if accurate and reliable means of assessing erythroid response is required to assess bone marrow recovery. Automated methods allow for the quantification of maturation within each reticulocyte, by measuring the amount of RNA present. The method of choice for our reticulocyte analysis was the Reticulocyte Maturation Index (RMI). The RMI was obtained by dividing the number of immature reticulocytes counted by the total number of reticulocytes counted producing a reportable value of International Units (IU). A normal Reticulocyte Maturation Index is 0.20 to 0.50 IU. The aim of the study was multifold. We wanted to prove that the Reticulocyte Maturation Index (RMI) is indeed the fastest means to assess bone marrow recovery in various types of transplants, including Bone Marrow Transplant (BMT) and Peripheral Blood Stem Cell Transplant (PBSCT). We also wanted to draw comparisons between allogeneic and autologous transplants, as well as further assessing different disease types. This was done by measuring the Reticulocyte Maturation Index (RMI), Absolute Neutrophil Count (ANe) and the Platelet Count (PLT) within the various groups. We further wanted to assess the effect of preconditioning treatment, Mononuclear Counts (MNC) and Colony Forming Unit - Granulocyte and Monocyte Counts (CFU-GM) on the early RMI response. These comparisons resulted in a need to establish a working range to determine patients response therein, and final outcome of the transplants. Finally we wanted to establish whether the "day 14" marrow biopsy is necessary, particularly if the three peripheral blood parameters, RMI, ANC and PLT were used as routine procedure following transplantation. The Reticulocyte Maturation Index (RMI) was measured on the Coulter EPICS ProfIle II flow cytometer; the ANC and PLT were measured on the Technicon H2 Haematology System. All other results such as the Mononuclear Counts (MNC), Colony Forming Unit - Granulocyte and Monocyte counts (CFU-GM), "day 14" and "day 28" bone marrow biopsies were retrieved from laboratory records. Forty nine transplant patients were evaluated for RMI over a period of six months, at the Department of Haematology, Groote Schuur Hospital, Cape Town. Four patients failed to engraft; and were not used in the calculations; but were evaluated as an aspect of the study in the final analysis. Forty five patients were analysed to establish the values used in the study, these patients were divided into eleven groups.
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Guo, Lei. "Study of the Influence of Nanosized Filler on the UV-Curable Resin Bonded Diamond Abrasive Tools." University of Toledo / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1461690140.
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Dickinson, Stephen John. "A building heating system simulation and optimisation tool incorporating bond graphs and genetic algorithms." Thesis, Lancaster University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.481623.
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Kuo, Jer-Lai. "Graph invariants a tool to analyze hydrogen bonding in ice and water clusters /." Columbus, OH : Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1039030658.
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Thesis (Ph. D)--Ohio State University, 2003.Title from first page of PDF file. Document formatted into pages; contains xiv, 108 p.: ill. (some col.). Includes abstract and vita. Advisor: Sherwin J. Singer, Dept. of Chemistry. Includes bibliographical references (p. 100-108).
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Sánchez, Ferrero Aitor. "Biomimetic hydrogels for in situ bone tissue engineering : nature-inspired crosslinking methods as a tool to tune scaffold physical properties." Doctoral thesis, Universitat Politècnica de Catalunya, 2015. http://hdl.handle.net/10803/373909.
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The global incidence of bone fractures, and subsequently that of non-healing ones, is expected to rise in the coming decades, mostly due to an increased risk of age-related conditions. Currently, the biomaterials field is moving towards the design of scaffolds mimicking the cell microenvironment to guide stem cells differentiation and recapitulate the development of target tissues. Biomimicry is a wide concept and several approaches have been adopted to produce cellinstructive scaffolds. Herein, we have explored the use of citric acid and lysyl oxidase, both of them related to bone nanostructure and mechanical performance, to develop scaffolds resembling the extracellular matrix of developing bone.
First, elastin-like recombinamers (ELRs) hydrogels were achieved through a one-step chemical crosslinking reaction with citric acid, a molecule currently considered to be essential for the proper performance of bone tissue. By systematically studying the crosslinking reaction and its contribution to hydrogel properties, we were able to control the architecture and stiffness of citric acid-crosslinked hydrogels while preserving the integrity of adhesion sequences in ELRs.
Interestingly, the use of citric acid conferred so-produced hydrogels the ability to nucleate calcium phosphate. Mechanically-tailored citric acid-crosslinked hydrogels were shown to be able to support the growth of human mesenchymal stem cells and to lead to seemingly biocompatible degradation products. Despite in vitro differentiation studies weren¿t conclusive as to their osteogenic potential, both mechanically-tailored and non-tailored citric acid-crosslinked hydrogels were shown to integrate into bone and to be partially degraded upon implantation in critical size defects in mouse calvaria. Despite cell invasion in mechanically-tailored scaffolds was seemingly lower than in non-tailored counterparts, both types of matrices allowed the formation of bone tissue, by intramembranous ossification, to a similar extent by the end of the study. At the time points selected for the in vivo study, both tailored and non-tailored hydrogels were found to be osteoconductive; osteoinduction was not observed in any of the cases. Mechanically-tailored hydrogels not being seemingly superior to control matrices at selected time points could to be due to (i) a high surface polymer density hindering cell invasion and thus delaying osteoinduction, or to (ii) a non-osteoinductive combination of properties (chemical + physical) despite hydrogels possessing theoretically osteoinductive stiffness.
These results point out that scaffolds must be seen as a whole given the high complexity of the in vivo cell niche, whose signals act synergistically to define cell behavior. Thus, more complex designs are required if recapitulation of bone development is to be targeted.
Additionally, recombinant lysyl oxidase (LOX) from human aorta was successfully produced in Escherichia coli to high purity. Despite achieving LOX with copper cofactor amounts and activity higher than those found in the literature, overall activity was low and the insolubilization of ELRs was not achieved, suggesting that novel expression and purification systems not compromising enzymatic activity are required if LOX is to be used to produce scaffolds.S'espera que la incidència global de fractures òssies, i per extensió la d'aquelles que no són capaces de consolidar per si soles, augmenti en les pròximes dècades, principalment degut a l'increment del risc de patologies associades a l'envelliment. Actualment, el camp dels biomaterials es mou cap al disseny de bastides que mimetitzen el microambient cel·lular per tal de guiar la diferenciació de cèl·lules mare i recapitular el desenvolupament de teixits diana. El biomimetisme és un concepte ampli i diverses aproximacions han sigut dutes a terme per tal de produir bastides capaces de guiar el comportament cel·lular. En aquesta tesi hem explorat l'ús d'àcid cítric i l'enzim lisil oxidasa, ambdós relacionats amb la nanoestructura i propietats mecàniques del teixit ossi, per desenvolupar bastides que mimetitzin la matriu extracel·lular de l'os en desenvolupament. En primer lloc, es va produir hidrogels basats en polímers recombinants de tipus elastina (Elastin-like recombinamers; ELRs) mitjançant una reacció d'entrecreuament en un pas amb àcid cítric, una molècula actualment considerada una peça essencial per l'adequat funcionament mecànic del teixit ossi. Havent fet un estudi sistemàtic de la reacció d'entrecreuament i de la seva contribució a les propietats dels hidrogels, vam ser capaços de controlar l'arquitectura i la rigidesa de les bastides entrecreuades amb àcid cítric, tot preservant la integritat de les seqüències d'adhesió cel·lular contingudes als ELRs. És interessant remarcar que l'ús d'àcid cítric com agent entrecreuant conferí als hidrogels capacitat de nucleació de fosfats de calci. Es va demostrar que els hidrogels entrecreuats amb àcid cítric i amb propietats mecàniques diana permeten el creixement de cèl·lules mare mesenquimals humanes i donen lloc a productes de degradació aparentment biocompatibles. Tot i que els estudis de diferenciació in vitro no van ser concloents pel que fa al potencial osteogènic d'aquestes bastides, tant les matrius amb propietats mecàniques diana com aquelles control van ser capaces d'integrar-se amb l'os natiu i van ser parcialment degradades un cop implantades en defectes de mida crítica en calotes de ratolí. Tot i que la invasió cel·lular en hidrogels amb propietats mecàniques diana va ser inferior en comparació amb l'observada en bastides control, ambdós tipus de matrius van permetre la formació d'os nou, mitjançant ossificació intramembranosa, en quantitats similars al final de l'estudi. Als punts temporals seleccionats, ambdós tipus de bastides van demostrar ser osteoconductives, però no es va observar evidències d'osteoconducció en cap cas. El fet que les bastides amb propietats mecàniques diana no fossin superiors a les matrius control pel que fa a formació òssia, podria ser degut a (i) a una elevada densitat superficial que hauria dificultat la invasió cel·lular i retrassat l'osteoinducció, o (ii) a una combinació de propietats (químiques + físiques) no osteoinductiva tot i que les bastides posseïen una rigidesa teòricament osteoinductiva. Aquests resultats demostren que les bastides han de ser vistes com un tot donada l'elevada complexitat del nínxol de cèl·lules mare in vivo, les senyals del qual actuen de forma sinèrgica per definir el comportament cel·lular. Així, és necessari assolir bastides amb un nivell de complexitat més elevat per tal de recapitular el desenvolupament ossi. Addicionalment, es va produir lisil oxidasa (LOX) d'aorta humana en forma recombinant a elevada puresa a partir de cultius d'Escherichia coli. Tot i que es va aconseguir produir LOX amb un contingut del cofactor coure i una activitat superiors a aquells trobats en la literatura, l'activitat de l'enzim va ser generalment baixa i no es va assolir la insolubilització d'ELRs. Això evidencia la necessitat de desenvolupar nous sistemes d'expressió i purificació de l'enzim per tal que aquest pugui ser aplicat a la producció de bastides.
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Zeevaart, Jan Rijn. "Metal-ion speciation in blood plasma as a tool in predicting the in vivo behaviour of potential bone-seeking radiopharmaceuticals /." Delft : Delft Univ. Press, 2001. http://www.gbv.de/dms/bs/toc/363844619.pdf.
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Yeager, Monica M. "Artificial Intelligence Algorithm to Classify Patient Specific Bone Density from DICOM Images and the Development of an Osteoporosis Screening Tool." University of Dayton / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1575913132552859.
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Schmidberger, Wolfgang. "Conceptual design, development and evaluation of an interactive exercise software tool for household technology courses in tertiary education." Aachen Shaker, 2009. http://d-nb.info/100104844X/04.
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Mooney, Barbara Logan. "An Integrated Graph-Theoretic Approach to Understanding Solvation Using a Novel Data Mining Tool, moleculaRnetworks." Diss., The University of Arizona, 2012. http://hdl.handle.net/10150/243096.
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An integrated graph-theoretic and geometric approach to the analysis of aqueous solvation of atomic ions is presented. This analysis makes use of a novel data-mining tool, moleculaRnetworks, to process data from molecular dynamics simulations. The workings and structure of this tool are discussed, along with the development and testing of its PageRank algorithm-based rapid solvation polyhedra classifier. The ability to classify instantaneous solvation polyhedra enables a finely detailed understanding of shell structure-behavior relationships, as water molecules simultaneously rearrange about ions, exchange with the bulk, and rearrange their hydrogen-bond network. The application of the tool to cation systems, including lithium, sodium, potassium, magnesium, calcium, and lanthanum, yields new insight into the mechanisms of water exchange about these ions. It is shown that in order for exchange events to occur, the solvation shell must "preorganize" to admit or expel a molecule of water: this preorganization is reflected in the mechanistic preference for each ion. The application of the tool to anion systems, including fluoride, chloride, and bromide, reveals that these ions have an extended effect on the reorientation ability of water molecules beyond their first solvation shell. Finally, when both ions are present, as in the potential of mean force simulation between lanthanum and chloride, structural rearrangements can be seen as the ions break through the barrier to form the contact ion pair. Taken together, these results show the utility of the moleculaRnetworks tool in broadening our understanding of aqueous ion solvation.
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Dixon, Toinette-Lee. "Implementation and evaluation of a bony structure suppression software tool for chest X-ray imaging." Master's thesis, University of Cape Town, 2012. http://hdl.handle.net/11427/11993.
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Includes abstract.Includes bibliographical references.
This project proposed to implement a bony structure suppression tool and analyse its effects on a texture-based classification algorithm in order to assist in the analysis of chest X-ray images. The diagnosis of pulmonary tuberculosis (TB) often includes the evaluation of chest X-ray images, and the reliability of image interpretation depends upon the experience of the radiologist. Computer-aided diagnosis (CAD) may be used to increase the accuracy of diagnosis. Overlapping structures in chest X-ray images hinder the ability of lung texture analysis for CAD to detect abnormalities. This dissertation examines whether the performance of texturebased CAD tools may be improved by the suppression of bony structures, particularly of the ribs, in the chest region.
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Ferreira, Costa Maria Cristiana. "Prediction of the risk of vertebral fracture in patients with metastatic bone lesions as a tool for more effective patients' management." Thesis, University of Sheffield, 2018. http://etheses.whiterose.ac.uk/22877/.
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Smith, Daniel L. "Selective incorporation of the C-F bond as a conformational tool in quadruplex DNA ligand design." Thesis, University of St Andrews, 2012. http://hdl.handle.net/10023/3169.
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Chapter 1 provides a general introduction to organofluorine chemistry and focuses on recent developments in fluorination techniques. It also details how the C–F bond influences conformational and physiochemical properties of organic molecules. Chapter 2 highlights the biological role of the telomere, telomerase and quadruplex DNA in cells. It discusses the inhibition of telomerase with small molecules that stabilise quadruplex DNA as a treatment for cancer. An overview of the development of structurally related telomerase inhibitors and recent X-ray crystallographic structural data with BSU6039 and BRACO-19 telomeric DNA is presented. Chapter 3 discusses the synthesis of fluorinated BSU6039 analogues for the investigation of the conformational effects of fluorine in 5-membered rings and its influence on binding with quadruplex DNA. These compounds have been successfully co-crystallised with telomeric DNA and their relative stabilisation of telomeric DNA has been assessed. The latter half of this chapter focuses on the co-crystal structures between (S,S)- and (R,R)-144 with Oxytricha nova telomeric DNA, discussing the key differences between the two stereoisomers. Chapter 4 details the synthesis of fluorinated BRACO-19 analogues. The syntheses of such fluorinated analogues were achieved through a base mediated coupling between 3,6-diaminoacridone and an α-fluorinated-β-amino ester. The α-fluorinated-β-amino ester was synthesised through a deoxyfluorination-mediated approach, using the stereochemistry of natural amino acids. Chapter 5 describes the stereo- and regio- selectivity of deoxyfluorination reactions with dipeptides bearing the β-amino alcohol functionality. Understanding this selectivity enabled the development of a method towards α-fluorination of tertiary amides. The application of this fluorination method with an orthogonally protected tertiary amide is described.
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Clément-Demange, Lise. "Établissement précoce des cellules métastatiques dans la moelle osseuse : implication d’une forme non glycosylée du récepteur de guidage axonal ROBO4." Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10077/document.
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Les métastases osseuses sont des complications de nombreux cancers tels que le cancer du poumon, du sein et de la prostate. Chez la femme, 70% des patientes présentant un cancer du sein avancé développent des métastases principalement ostéolytiques. Ce type de métastases est associé à une destruction importante de l'os causant chez les patientes des douleurs osseuses et des fractures pathologiques. Les traitements actuellement dispensés tels que les bisphosphonates et le denosumab ne sont pas curatifs mais seulement palliatifs, il est donc indispensable d'identifier de nouveaux facteurs impliqués dans la progression métastatique afin d'améliorer le pronostic et d'imaginer de nouvelles approches thérapeutiques. Dans ce contexte, une analyse transcriptomique comparative a montré que les gènes codant les récepteurs de guidage axonal ROBO1 et ROBO4 étaient surexprimés dans une sous-population de cellules de cancer du sein MDA-MB-231 qui métastasent spécifiquement à l'os (nommée B02). De manière intéressante, une expression élevée de ROBO4 dans les tumeurs primaires de patientes atteintes d'un cancer du sein corrèle avec un mauvais pronostic et un risque accru de rechute à l'os. Chez la souris, une réduction de 50% de la charge tumorale a été observée lorsque les cellules B02 déplétées en ROBO4 ont été inoculées dans la glande mammaire de souris ; et le ciblage des cellules parentales B02 avec un anticorps anti-ROBO4 avant l'injection intra-tibiale diminue l'incidence de la formation de colonies de cellules tumorales. In vitro, la co-culture des cellules B02 avec des cellules ostéoblastiques murines MC3T3-E1 a entraîné une augmentation de la production de SLIT2, le ligand naturel des récepteurs ROBO, par les cellules MC3T3-E1. De plus, le traitement avec un anticorps anti-ROBO4 réduit considérablement l'adhésion des cellules B02 sur les cellules MC3T3-E1. Par ailleurs, la surexpression de ROBO4 dans d'autres modèles cellulaires de cancer du sein a conduit à mettre en évidence la présence d'une glycoforme de ROBO4. L'étude des deux isoformes de ROBO4 (glycosylée et non glycosylée) a révélé le caractère agressif de la forme non glycosylée comparée à la forme glycosyléeBone metastasis is a complication of many cancers such as lung, breast and prostate. In women, 70% of patients with advanced breast cancer predominantly develop osteolytic metastases. This type of metastasis is associated with significant bone destruction in patients causing bone pain and pathological fractures. The current treatments, such as bisphosphonates and denosumab, are not curative but only palliative, so it is essential to identify new factors involved in the metastatic progression to improve prognosis and to devise new therapeutic approaches. In this context, a comparative transcriptomic analysis demonstrated that axon guidance ROBO1 and ROBO4 receptors were overexpressed in a subpopulation of MDA-MB-231 breast cancer cells that only metastasize to bone (referred to as B02). Interestingly, high ROBO4 expression in primary tumors from patients with breast cancer correlated with poor prognosis and increased risk of relapse to bone. In mice, a 50% reduction in tumor burden was observed when ROBO4-depleted B02 cells were inoculated in the mammary fat pad of mice; and targeting of parental B02 cells with an anti-ROBO4 antibody before intra-tibia inoculation decreased the incidence of tumor cell colony formation. In vitro, the co-culture of B02 cells with murine MC3T3-E1 osteoblastic cells increased SLIT2 production, the primary ligand of ROBO receptors, by MC3T3 cells. Further, the treatment with an anti-ROBO4 antibody dramatically reduced B02 cell adhesion to MC3T3-E1 cells. Moreover, over-expression of ROBO4 in other models of breast cancer led to the discovery of a glycoform of ROBO4. The study of the two ROBO4 isoforms (glycosylated and non-glycosylated) revealed the aggressive nature of the non-glycosylated form compared to the glycosylated form. These results provide strong evidence that the axon guidance receptor ROBO4 is involved in bone metastasis formation and that the use of an antibody directed against the non-glycosylated form of this receptor could lead to the development of innovative therapies to prevent metastasis formation in the bone marrow
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Oestreich, Henrik Stefan, and Karimi Nima Marandi. "A study of the dynamics of the Swedish Green Bond Market : From a niched to a mainstream tool for sustainable development." Thesis, KTH, Industriell Management, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-254245.
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The phenomenon of climate change is widely recognized and declared as the single most threatening issue of the 21st century (UN Environment, 2018). In this context, the presented study is aligned with scientific research on the domain of sustainable development and sustainability transitions aiming to counterbalance climate change and its impact on this planet as much as possible. This research focuses on Green Bonds as a financial tool to promote this kind of climate-resilient transition. Professionals from the financial sectors of the Swedish Green Bond market were interviewed, reflecting current opinions and strategies of one of the most developed and progressive nations in the world. The goal is to understand the dynamics behind the development of the Green Bond market using the Multi-Level Perspective framework and to find out to what extent these experts view Green Bonds as a tool in the process of sustainability transitions. The findings firstly point out the role of the different actors of the Green Bond market, describing the interactions between investors, issuers banks, politics and advisors. In addition, the results show that the opinions on drivers and barriers amongst the interviewees and between the interviewees and literature differ somewhat. In particular, greenwashing, lacking transparency and missing standardization are seen by some of the different interviewed stakeholders to be less barriers but rather as opportunities. In conclusion, this study points out the particular influence that politics, as representant of the strongly environmentally aware people of Sweden, occupy in steering the market’s development and describes its importance as regulatory drivers of Green Bonds as a tool for sustainability transitions and sustainable development.Mänskligheten står inför en global utmaning; att kollektivt bekämpa den mänskligt orsakade klimatförändringen (UN Environment, 2018). Det är från detta sammanhang som denna studie ursprungar, där teorier inom vetenskaplig forskning för området hållbarhetsutveckling och hållbarhet förändringar används för att bekämpa klimatförändringens inverkan. Denna forskning fokuserar särskilt på gröna obligationens roll för en hållbar klimatrelaterad utveckling i det svenska samhället. För att utvärdera den svenska marknaden för gröna obligationer intervjuades experter inom området utvalda på basis av post och sektor. Målet med en kvalitativ forskningsmetod är att förstå de bakomliggande faktorerna för den progressiva utvecklingen i Sverige. Detta görs ytterligare genom ”The Multi-Level Perspective framework” för att kontextualisera experternas insyn på hur gröna obligationer kan användas som verktyg för hållbarhetsutveckling. Kartläggningen användes för att beskriva dynamiken mellan obligations utfärdaren, investerare, banker samt rådgivare i Sverige. Intervjuerna visade på nyanser inom dagens teori och praktik avseende hur man utvärderar tillväxten på den gröna obligationsmarknaden och framförallt gällande integritet faktorer som standardisering och transparens. Ett bristande ramverk kan ses som en möjlighet för tillväxt istället för ett hinder. Sammanfattningsvis understryker undersökningen politikernas inflytande för att kunna omvandla gröna obligationer från en nisch till en standardprodukt i samhället. Detta påvisar effektiviteten inom den svenska gröna obligationsmarknaden, där hög grad av miljömedvetenhet hos befolkningen blivit representerad i politiken.
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Vu, Hai Vinh. "Salivary antigenic proteins from Ixodidae and Anopheles : a novel tool for vector-borne diseases monitoring." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM5052/document.
Full textAbstract:
Les MVs sont un problème majeur de santé publique. L'émergence des MVs nécessite de nouveaux outils pour la surveillance de ces maladies. Ce projet s’intéresse aux deux familles de vecteurs: Ixodidae (R. sanguineus, D. reticulatus et I. ricinus) et Anophèles (An. gambiae s.l. et An. funestus). Une revue synthétise les données actuelles des MTTs et leur vectors, avant de présenter des méthodes de surveillance de ces maladies. La partie expérimentale s'est concentré sur l'élaboration de méthodes pour la sélection des utiles protéines salivaires pour l'évaluation du contact hôte-vecteur. Pour Ixodidae, la stratégie antigénique utilisée a permis d’identifier des protéines salivaires antigéniques communes et spécifiques d’espèce de ces tiques. Ces protéines pourraient servir pour l’évaluation de l’exposition de l’hôte aux Ixodidae. Pour Anophèles, la stratégie candidate utilisée a révélé une protéine salivaire antigénique d’Anopheles (f-5’nuc) pouvant être marqueur prometteur distinguant l'exposition aux Anophèles au niveau de l'espèce. Pour conforter ces résultats, l’établissement d’une relation entre la cinétique des réponses d'anticorps de l’hôte contre ces candidats salivaires, la faune Culicidienne et la variation de densité des populations de moustiques est en cours. Ce projet a souligné que tous les deux vectors peuvent induire une réponse immunitaire chez leur hôte contre des protéines salivaires antigéniques injectées. Il a permis également d’identifier des protéines salivaires permettant la discrimination de l'exposition d'hôte aux vecteurs au niveau du genre ou de l’espèce, offrant de nouvelles stratégies pour la surveillance des MVsVector-borne diseases (VBD) are a major health problem worldwide. The emergence of VBD requires novel monitoring tools. The present project focused on two vector families: Ixodidae (R. sanguineus, D. reticulatus and I. ricinus) and Anopheles (An. gambiae s.l. and An. funestus). A review updates the repartition of TBD, their vectors in Europe, prior to present the different tools for monitoring of TBD transmission. The experimental part focused on establishing methods for selection of useful vector salivary proteins for host-vector contact assessment. Concerning Ixodidae, the studied antigenic strategy successfully identified the shared and discriminant tick salivary antigenic proteins. These identified proteins could be an useful tool to measure host exposition to Ixodidae bites. Concerning Anopheles, the studied candidate strategy revealed an salivary antigenic protein ( f-5’nuc) that could be a promising antigenic marker to distinguish malaria vector exposure at the species level. To comfort these results, the relationship between the kinetic host antibody response against anopheline salivary candidates and the Anopheles fauna population and density variations is under progress. The present work underlined that both two studied vector families following blood meal can elicit a host antibody response against injected vector salivary antigenic proteins. This project proposed for the first time some vector salivary proteins allowing discriminating host exposure to vector bites from genus to species level, opening new strategies for VBD monitoring at the individual and population levels
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Birkhold, Annette Isabell [Verfasser], Georg N. [Akademischer Betreuer] Duda, Peter [Akademischer Betreuer] Fratzl, Marc [Gutachter] Kraft, Georg N. [Gutachter] Duda, and Peter [Gutachter] Fratzl. "A 4D imaging approach to monitor bone remodeling : development, design, validation and first applications of a tomography-based medical image processing method and tool for enhanced visualization and quantification of patho-physiological dynamic structural processes in bone / Annette Isabell Birkhold ; Gutachter: Marc Kraft, Georg N. Duda, Peter Fratzl ; Georg N. Duda, Peter Fratzl." Berlin : Technische Universität Berlin, 2016. http://d-nb.info/1156180007/34.
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Burns, Zackory T. "Quantifying the sociality of wild tool-using New Caledonian crows through an animal-borne technology." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:16db8026-53e4-4fb0-aa69-80d7cc34e183.
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New Caledonian crows (NC crows; Corvus moneduloides) are the most prolific avian tool-users and crafters, using up to three unique tool types derived from numerous plant materials. Since the discovery that wild populations of NC crows use and manufacture different tools in different locations with no measured environmental correlates to these distributions, the process by which NC crows acquire their tool-oriented behavior has been investigated. Two major findings were discovered in 2005: NC crows have a genetic predisposition to manipulate stick like objects, and they increase their rate of manipulation when exposed to social influences. Since then, much of the research into the sociality of wild NC crows has focused on direct social influences, especially the parent-juvenile relationship, yet no social network of wild NC crows has been described. In my thesis, I characterized a new proximity-logging device, Encounternet, and outline a four-step plan to assess error in animal borne devices; uncovered drivers, such as relatedness, space-use, and environmental factors, of wild NC crow sociality, and experimentally manipulated the social network, revealing immediate changes to the number of day-time and roosting partners, the breakdown of first-order relatedness driving sociality, and an increase in the amount of time NC crows associate; and revealed an indirect pathway via tools left behind by conspecifics allowing for the transmission of tool-properties between unrelated NC crows. Altogether, I furthered our understanding of wild NC crow sociality through the use of an animal-borne device, experimental manipulation in the wild measuring the response of the NC crow social network, and demonstrated the utility of animal-borne devices in mapping the network of a population of wild birds.
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McRostie, V. B. "The role of plant production in subsistence and cultural changes during the formative period in the Atacama Puna, Southern Andes, Chile (1400BC-500AD) : a re-evaluation based on the analyses of microfossils attached to hoes and grinding tools, and isotopic analyses of human bones." Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1408188/.
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The onset of agriculture is an important research topic in archaeology. Nonetheless, several areas of the world still lack sufficient datasets to participate critically within this debate. This is the case for the western slope of the Puna de Atacama, where explanations about plant production have been based on limited evidence resulting in assumptions about the role of agriculture associated with the Formative. More recent research in the Americas has acknowledged the diversity of developments taking place during the Formative period, including regional differences in the degree of wild and domestic plants food production. This research identifies and analyses new evidence in order to revaluate current hypothesis and models of plant production in the Atacama. The analyses are based on the identification of plant microfossils taken from hoes and grinding tools and isotopes within human bones (δ13Ccol, δ13Cap, δ15N, δ18O, Sr87/Sr86). The result of these analyses argues that crops in the area were limited or absent and highlights different levels and managements for native plants such as Scirpus, Cactaceae and still unidentified tubers. Insights’ regarding an anthropical origin of Prosopis forests and a silvo-pastoralist system provides a new model for the Formative of this arid highlands and the American continent.
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Backwell, Lucinda Ruth. "A critical assessment of southern African 'early hominid bone tools'." Thesis, 2014.
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Atchley, Edward Scott. "Design and implementation of the L-Bone and logistical tools." 2002. http://etd.utk.edu/2002/AtchleyEdward.pdf.
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Thesis (M.A.)--University of Tennessee, Knoxville, 2002.Title from title page screen (viewed Sept. 4, 2002). Thesis advisor: James Plank. Document formatted into pages (viii, 51 p. : ill., col. map). Vita. Includes bibliographical references (p. 44-46).
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Van, Ryneveld Karen. "Bone tools from the early hominid sites, Gauteng: an experimental approach." Thesis, 2003. http://hdl.handle.net/10539/18830.
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Thesis (M.Sc. (Palaeoarchaeology))--University of the Witwatersrand, Faculty of Science, 2003This project was inspired by the identification of 108 bone tools (dated roughly to between 2 and 1 Mya) from sites in the Cradle of Humankind World Heritage Site, Gauteng. An experimental study was lUldertaken in an attempt to answer the basic question of "what caused modification marks on early hominid bone tools?" Five experimental tools were used in each of seven different task oriented experiments. The purpose of this project was to broaden the existing database of experimentally employed bone tools and the associated process-pattern relationships. Analysis was based on an optical comparison of primarily microscopically, but also macroscopically visible usewear patterns observed on the experimental tools. The experimental data were then used to make inferences on a middle range theoretical level regarding the use of the fossil specimens and comment on the currently held opinions.
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Teixeira, Sónia Manuela Arantes. "Bisphosphonate-based ionic liquids as potential pharmacological tools for breast cancer-induced bone osteolytic metastasis." Doctoral thesis, 2018. https://hdl.handle.net/10216/113134.
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Teixeira, Sónia Manuela Arantes. "Bisphosphonate-based ionic liquids as potential pharmacological tools for breast cancer-induced bone osteolytic metastasis." Tese, 2018. https://hdl.handle.net/10216/113134.
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Vavrasek, Jessica Lee. "Faunal Remains from the Pine Hill Site (PS-6), St. Lawrence County, New York." 2010. http://trace.tennessee.edu/utk_gradthes/839.
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The Pine Hill collection was discovered in the archaeology lab at State University of New York College at Potsdam after remaining unstudied for over 30 years since its initial excavation in the 1960s and 1970s. Pine Hill has been identified as a fifteenth century St. Lawrence Iroquois village site, located in St. Lawrence County, New York. The faunal remains and bone tools from the site indicate food procurement strategies, seasonal activities, the presence of discrete activity areas at the site, and the production and use of a wide range of bone tools. Replication experiments conducted on several bone tool types provide insight about how these tools were made, used, and how quickly they might be discarded. As one of the first reports on a St. Lawrence Iroquois site in the region, this study presents important information about this group.
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Pirraco, Rogério. "Co-cultures and cell sheet engineering as relevant tools to improve the outcome of bone tissue engineering strategies." Doctoral thesis, 2011. http://hdl.handle.net/1822/19686.
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Taking into consideration the complex biology of bone tissue it is quite clear that the
understanding of the cellular interactions that regulate the homeostasis and
regeneration of this remarkable tissue is essential for a successful Tissue Engineering
strategy. The in vitro study of these cellular interactions relies on co-culture systems, a
tremendously useful methodology where two or more cell types are cultured at the
same time. Such strategy increases the complexity of typical monoculture systems,
allowing the in vitro settings to closely mimic the in vivo environment. Moreover, 2D coculture
systems have been extensively used by cell biologists to study cell interactions
as an attempt to understand specific cellular mechanisms and signalling pathways. The
interaction between osteoblasts/ osteoprogenitor cells and different cell types relevant
within the bone Tissue Engineering context, namely mononuclear cells from peripheral
blood and umbilical cord blood and fibroblasts, has been addressed in the first part of
this thesis. The different co-cultures showed that mononuclear cells from peripheral
blood were capable of accelerating the osteogenic differentiation of human bone
marrow stromal cells by producing BMP-2. On the other hand, osteoblasts cultured on
carrageenan membranes were capable of supporting the culture of endothelial
progenitors cells present in the mononuclear fraction of umbilical cord blood that
contributed to the in vivo angiogenesis after implantation in an inflammatory setting.
Furthermore, fibroblasts, which are key players in the formation of fibrotic tissue after a
biomaterial implantation, were shown to decrease the osteogenic activity of osteoblasts
through gap junctional communication.
A serious limitation of the paradigmatic use of scaffolds for bone Tissue Engineering is
the lack of oxygen and nutrient supply to the cells in the core of the engineered
construct leading to cell necrosis at the bulk of the constructs. Furthermore, foreign
body response to the implanted biomaterial is a frequent reaction of the host and has as a consequence the formation of fibrotic tissue surrounding the implant. The use of
cell sheet engineering for bone Tissue Engineering can potentially avoid those
shortcomings. One of the explored strategies comprised the production of osteogenic
cell sheets using this technology. Its potential for in vivo bone formation was analyzed
and the formation of vascularized bone tissue with a marrow was originally
demonstrated by implanting a single osteogenic cell sheet in a nude mice model.
Furthermore, in order to promote vascularization, co-cultured osteogenic cell sheets
with endothelial cells were also created. Endothelial cells, stacked in between
osteogenic cell sheets, were proven to contribute to new vessel formation and
increased bone formation in vivo
This thesis demonstrates that monocytes/macrophages from peripheral blood can
accelerate the osteogenic differentiation of osteoprogenitor cells while fibroblasts, have
a deleterious effect on the osteogenic phenotype of osteoblasts. In addition, within an
inflammatory host reaction, cells from the mononuclear fraction of umbilical cord blood
were capable of contributing to new blood vessel formation after co-culture with
osteoblasts. Moreover, when using the cell sheet technology to fabricate a bone tissue
engineering construct, endothelial cells were also shown to improve in vivo bone
formation.Considerando a complexa biologia do tecido ósseo torna-se claro que compreender as interacções celulares que regulam a homeostasia e regeneração deste tecido notável, é de extrema importância numa estratégia de Engenharia de Tecidos. O estudo in vitro destas interacções celulares baseia-se em sistemas de co-cultura, uma metodologia de grande utilidade onde dois ou mais tipos de células diferentes são cultivados simultaneamente e no mesmo espaço. Estes sistemas representam um aumento de complexidade, em relação aos sistemas de monocultura, que permite que as condições in vitro mimetizem melhor o ambiente in vivo. Além disso, sistemas de cultura 2D têm sido muito utilizados por biólogos no estudo de interacções celulares numa tentativa de compreender os mecanismos e vias de sinalização envolvidas. A interacção entre osteoblastos ou células osteoprogenitoras com células mononucleares do sangue periférico e do cordão umbilical, e com fibroblastos para aplicações em Engenharia de Tecido Ósseo foi estudada na primeira parte desta tese. As diferentes co-culturas permitiram mostrar que as células mononucleares do sangue periférico são capazes de acelerar a diferenciação osteogénica de células do estroma de medula óssea humana através da produção de proteína morfogenética do osso 2 (BMP-2). Por outro lado, foi também demonstrado que osteoblastos cultivados em membranas de carragenano suportam a cultura de células progenitoras endoteliais presentes na fracção mononuclear de sangue do cordão umbilical humano e que estas, por sua vez, contribuem para a angiogénese in vivo e em condições inflamatórias. Além disso, foi mostrado que fibroblastos, células-chave na deposição de tecido fibrótico após a implantação de um biomaterial, inibem a actividade osteogénica de osteoblastos através da comunicação por Gap Junctions. A utilização paradigmática de matrizes de suporte para a Engenharia de Tecido Óssea tem como limitação grave a falha de fornecimento de oxigénio e nutrientes às células no interior da matriz construída levando à necrose dessas mesmas células. Além disso, a resposta do hospedeiro à implantação de corpos estranhos, como matrizes tridimensionais, tem como consequência frequente a formação de tecido fibrótico à volta do implante. A aplicação da Engenharia de cell sheets na Engenharia de Tecido ósseo tem a expectativa de ultrapassar estas limitações. Uma das estratégias exploradas teve como base a produção de cell sheets osteogénicas utilizando esta tecnologia. O potencial destas cell sheets para induzir a formação de osso foi analisada in vivo tendo sido demonstrada a formação de osso vascularizado com uma estrutura medular organizada após a implantação de uma única cell sheet num modelo de ratinho nude. Além disso, numa tentativa de promover a vascularização, foram criadas cell sheets osteogénicas co-cultivadas com células endoteliais. Estas, quando cultivadas entre cell sheets osteogénicas sobrepostas, contribuíram para a formação de novos vasos in vivo bem como para o aumento da formação de novo osso. Esta tese demonstra que monócitos/macrófagos do sangue periférico podem acelerar a diferenciação osteogénica de progenitores osteogénicos enquanto os fibroblastos exercem um efeito negativo no fenótipo osteogénico de osteoblastos. Mais ainda, no contexto de uma reacção inflamatória do hospedeiro, ficou comprovado que células da fracção mononuclear do sangue do cordão umbilical participam na formação de novos vasos após co-cultura com osteoblastos. Além disso, as células endoteliais adultas, quando combinadas com cell sheets osteogénicas, promovem a formação de osso in vivo.
Fundação para a Ciência e a Tecnologia (FCT) - SFRH / BD / 44893 / 2008.
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Brownlee, Kevin M. "Bone and antler tools from the Victoria Day site (Manitoba) : building bridges with First Nation communities through experimental archaeology." 2005. http://hdl.handle.net/1993/7934.
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Archaeological research in the province of Manitoba is shifting towards collaborative projects with First Nation communities. The aim of this project was to establish a collaborative model for Indigenous research through the involvement of the First Nation community and the use of experimental archaeology. Members of the Nisichawayasihk Cree Nation were involved throughout the entire research process, from excavation to analysis. Recent archaeological work in northern Manitoba has recovered several human burials in a remarkable state of preservation. Individuals interred with bone and antler tools provide us a rare glimpse into the use of perishable materials. This research project focuses on the bone and antler tools associated with burial of an adolescent male, dating to 4,000 BP from the Victoria Day site (GkLr-61, feature 2) on Threepoint Lake. The tools were studied following an 'operational sequence' or 'chaine operatoire' method of analysis, focusing on the entire "life cycle" including the acquisition of raw materials, the manufacturing process, use and re-use of the tool and final deposition. Interviews were conducted with members of the Nisichawayasihk Cree Nation and their insights guided the use of experimental archaeology to evaluate tool performance. The results of this project provide important insights into the culture of the people who lived in the Boreal Forest of Manitoba 4,000 years ago and are presented in a format that is meaningful to both the Indigenous community and archaeologists.