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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Taphonomic contribution of large mammal butchering experiments to understanding the fossil record

Leenen, Andrea 07 July 2011 (has links)
The primary goal of this project is to create a modern comparative collection of complete large bovid skeletons that record butchery marks made by stone tools. Four different raw materials commonly found in the southern African archaeological record (chert, quartzite, dolerite and hornfels) were selected for flake production. Butchery was conducted on three cows by modern Bushmen subsistence hunters skilled in the processing of animal carcasses. They form part of a relatively isolated group of !Xo-speaking Bushmen resident in the village of Kacgae in the Ghanzi district of western Botswana. The study focuses on characterising the type and conspicuousness of stone-generated butchering marks on bones under low magnification, and documenting patterning including anatomical location, number and orientation. Due to the fact that numerous natural events and human practices modify bones, unequivocal interpretation of bone modifications is sometimes difficult. Further to this, mimics, which are a result of non-human activity, produce the same or qualitatively similar patterns that complicate positive identification of butchery marks made by hominins. Reliable measures are required for interpretation of fossil bone modifications, and controlled actualistic observations provide a direct link between the process of modification (stone tool butchery aimed at complete flesh removal) and the traces produced. A number of taphonomic processes, including bone modification by various animals and geological processes are recorded in comparative collections housed at institutions in the province of Gauteng in the Republic of South Africa. These provide reference material for taphonomists attempting to identify agents responsible for the modification and accumulation of fossil bone assemblages, particularly from early hominin cave sites in the Sterkfontein Valley. However, no reference material exists for hominin modification of bone, and thus motivates for the collection of such traces. The modern comparative collection produced by this study shows butchery marks inflicted exclusively by habitual hunters who are also skilled butchers, and provides a resource for researchers to help accurately identify hominin-produced butchery marks on fossil bones. The accompanying catalogue records the type and conspicuousness, anatomical location and orientation of the butchery marks and provides a controlled sample against which a fossil assemblage can be compared. Results indicate no consistent patterning in the intensity of butchery marking with regard to the type of stone tool material that is utilised. However, a high number of butchery marks per surface area were recorded for most stone tool materials for certain skeletal elements including the mandible, ribs, scapula and humerus. Overall, there are indications that raw material influences butchery marking, however, the small sample size hinders the potential of an identifiable pattern with regard to the type of raw material from which the stone tools responsible for the butchery marks were produced. Furthermore, the vast range of variables that can exist during the butchery process contribute to the equivocal nature of the results. Additional research is required, some of it ongoing, which expands the sample of stone tool butchering, utilises iron tools and investigates ethnographic differences in butchering techniques.
2

Avaliações termográfica e ultrassonográfica Power Doppler de falhas ósseas induzidas em tíbias de ovinos / Thermographic and Power Doppler evaluation of induced bone defect in the ovine tibia

Silva, Danielle Cristinne Baccarelli da 11 October 2016 (has links)
Na ortopedia humana e veterinária é frequente a necessidade de reparação óssea após grandes traumas e fraturas, sendo indispensável o uso de implantes para correção estética e funcional dos membros. Os materiais de origem biológica, conhecidos como biomateriais, estão sendo usados principalmente na confecção de próteses e órteses. A utilização de ferramentas não invasivas e com menor ônus no pós-operatório de cirurgias ortopédicas está em grande avanço, e a utilização do Power Doppler na visualização de neovascularização auxilia na previsão de regeneração, assim como as variações térmicas verificadas pela termografia auxiliam na previsão de não-união, ou processo inflamatório exacerbado. Falhas ósseas foram realizadas nas tíbias de ovinos e preenchidas com biomaterial à base de quitosana, colágeno e hidroxiapatita, sendo que um membro foi considerado controle e outro membro tratado segundo estudo randomizado. Foram realizadas avaliações termográficas e por ultrassonografia Power Doppler em todos os animais do estudo, semanalmente, por 56 dias do período pós-operatório. Não houve diferenças significativas com relação à temperatura mínima, máxima e média entre os grupos com biomaterial e controle nas imagens termográficas. Houve variações estatísticas com relação ao tempo dentro de ambos os grupos. Com relação à presença de vasos na ultrassonografia Power Doppler não houve diferenças estatísticas entre os grupos, exceto no dia 21 (p = 0,031). O Power Doppler foi realizado com duas configurações PRF 1 (1,4 kHz) e PRF 2 (6, 7 kHz). Houve diferença significativa entre os grupos com biomaterial e controle na PRF 1 nos dias 21 (p = 0,016) e 28 (p = 0,031), onde o grupo controle apresentou maior número de vasos nos dois momentos. Não houve diferença estatisticamente significativa com relação à mesma avaliação com a PRF 2. Na observação cruzada entre presença de vasos e temperatura houve diferença significativa no dia 21 dos membros com biomaterial, para a temperatura mínima (p = 0,049), máxima (p = 0,056) e média (p = 0,052), onde nos membros que não apresentaram vasos esta mostrou-se maior quando comparada aos que possuíam neovascularização, o que não ocorreu no caso dos membros controles. Dentro das possibilidades de avaliação que os exames de imagem fornecem, a termografia e a ultrassonografia Power Doppler mostraram-se ferramentas não invasivas de avaliação pós-operatória de processo inflamatório e neovascularização, e não houve indícios de complicações relacionadas ao biomaterial / Trauma and large fractures frequently need repair in human and veterinary medicine, and bone implants are imperative for esthetics and functional limb correction. Biological material, known as biomaterials has been used in the manufacture of prostheses and orthoses. Non-invasive methods with lower burden for the orthopedic postoperative period are in great advance, and Power Doppler for neovascularization evaluation aid in regeneration forecast, such as thermal variations visualized with thermography supports non-union or inflammation exacerbation. Bone defects was performed in both ovine tibia and it was filled with chitosan, collagen and hydroxyapatite biomaterial. One limb was filled with the biomaterial and the other one was left as control following randomized study. Thermographic and Power Doppler ultrasonography assessment was performed in all animals, weekly, for 56 postoperative days. There was no difference in minimum, maximum and average temperature between the biomaterial and control groups in the thermographic evaluation. Statistical variations were visualized according to the time in both groups. Neovascularization evaluated by Power Doppler showed no statistic variation between groups, except at 21 postoperative days (p = 0,031). Two Power Doppler PRF configuration was performed PRF 1 (1,4 kHz) e PRF 2 (6, 7 kHz). Significant difference among biomaterial and control groups was noted with PRF 1 at the 21 (p = 0,016) and 28 (p = 0,031) postoperative days, in which the control group demonstrated higher number of vessels, in both moments. No statistical differences were founded in the same evaluation with PRF 2. In crossing information (neovascularization presence and temperature) at the 21 day, the biomaterial group presented higher minimum (p = 0,049), maximum (p = 0,056) and average (p =0,052) in the without vessels limbs. This was not visualized in the control group. Within the imaging evaluation possibilities, thermography and Power Doppler ultrasonography presented noninvasive potential for the postoperative period inflammatory and neovascularization evaluation and there was no evidence of biomaterial related complications
3

Avaliações termográfica e ultrassonográfica Power Doppler de falhas ósseas induzidas em tíbias de ovinos / Thermographic and Power Doppler evaluation of induced bone defect in the ovine tibia

Danielle Cristinne Baccarelli da Silva 11 October 2016 (has links)
Na ortopedia humana e veterinária é frequente a necessidade de reparação óssea após grandes traumas e fraturas, sendo indispensável o uso de implantes para correção estética e funcional dos membros. Os materiais de origem biológica, conhecidos como biomateriais, estão sendo usados principalmente na confecção de próteses e órteses. A utilização de ferramentas não invasivas e com menor ônus no pós-operatório de cirurgias ortopédicas está em grande avanço, e a utilização do Power Doppler na visualização de neovascularização auxilia na previsão de regeneração, assim como as variações térmicas verificadas pela termografia auxiliam na previsão de não-união, ou processo inflamatório exacerbado. Falhas ósseas foram realizadas nas tíbias de ovinos e preenchidas com biomaterial à base de quitosana, colágeno e hidroxiapatita, sendo que um membro foi considerado controle e outro membro tratado segundo estudo randomizado. Foram realizadas avaliações termográficas e por ultrassonografia Power Doppler em todos os animais do estudo, semanalmente, por 56 dias do período pós-operatório. Não houve diferenças significativas com relação à temperatura mínima, máxima e média entre os grupos com biomaterial e controle nas imagens termográficas. Houve variações estatísticas com relação ao tempo dentro de ambos os grupos. Com relação à presença de vasos na ultrassonografia Power Doppler não houve diferenças estatísticas entre os grupos, exceto no dia 21 (p = 0,031). O Power Doppler foi realizado com duas configurações PRF 1 (1,4 kHz) e PRF 2 (6, 7 kHz). Houve diferença significativa entre os grupos com biomaterial e controle na PRF 1 nos dias 21 (p = 0,016) e 28 (p = 0,031), onde o grupo controle apresentou maior número de vasos nos dois momentos. Não houve diferença estatisticamente significativa com relação à mesma avaliação com a PRF 2. Na observação cruzada entre presença de vasos e temperatura houve diferença significativa no dia 21 dos membros com biomaterial, para a temperatura mínima (p = 0,049), máxima (p = 0,056) e média (p = 0,052), onde nos membros que não apresentaram vasos esta mostrou-se maior quando comparada aos que possuíam neovascularização, o que não ocorreu no caso dos membros controles. Dentro das possibilidades de avaliação que os exames de imagem fornecem, a termografia e a ultrassonografia Power Doppler mostraram-se ferramentas não invasivas de avaliação pós-operatória de processo inflamatório e neovascularização, e não houve indícios de complicações relacionadas ao biomaterial / Trauma and large fractures frequently need repair in human and veterinary medicine, and bone implants are imperative for esthetics and functional limb correction. Biological material, known as biomaterials has been used in the manufacture of prostheses and orthoses. Non-invasive methods with lower burden for the orthopedic postoperative period are in great advance, and Power Doppler for neovascularization evaluation aid in regeneration forecast, such as thermal variations visualized with thermography supports non-union or inflammation exacerbation. Bone defects was performed in both ovine tibia and it was filled with chitosan, collagen and hydroxyapatite biomaterial. One limb was filled with the biomaterial and the other one was left as control following randomized study. Thermographic and Power Doppler ultrasonography assessment was performed in all animals, weekly, for 56 postoperative days. There was no difference in minimum, maximum and average temperature between the biomaterial and control groups in the thermographic evaluation. Statistical variations were visualized according to the time in both groups. Neovascularization evaluated by Power Doppler showed no statistic variation between groups, except at 21 postoperative days (p = 0,031). Two Power Doppler PRF configuration was performed PRF 1 (1,4 kHz) e PRF 2 (6, 7 kHz). Significant difference among biomaterial and control groups was noted with PRF 1 at the 21 (p = 0,016) and 28 (p = 0,031) postoperative days, in which the control group demonstrated higher number of vessels, in both moments. No statistical differences were founded in the same evaluation with PRF 2. In crossing information (neovascularization presence and temperature) at the 21 day, the biomaterial group presented higher minimum (p = 0,049), maximum (p = 0,056) and average (p =0,052) in the without vessels limbs. This was not visualized in the control group. Within the imaging evaluation possibilities, thermography and Power Doppler ultrasonography presented noninvasive potential for the postoperative period inflammatory and neovascularization evaluation and there was no evidence of biomaterial related complications

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