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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

The impacts of climate and the environment on human skeletal morphology during the Holocene in north China

Siew, Yun Ysi January 2017 (has links)
This dissertation investigates the temporal and regional variation in human skeletal morphology in relation to climate and the environment in Holocene China. Linking skeletal morphology to the changes in climate, subsistence strategy and socio-political development has been well-documented in various geographical areas. Although a general pattern has been observed among different populations, it is evident that local factors have played an equally important role in human morphological variation. China was chosen in this dissertation because its diverse geographical, historical and cultural background provides an ideal setting in which to elucidate human biological responses to a variety different external forces and stimuli. A total sample of 533 adult skeletons, spanning from the mid-Neolithic to the twentieth century, was examined. These skeletons represent the ancient agriculturalists, nomadic pastoralists and agropastoralists inhabiting in contemporary Northeast China and modern humans from South China. This dissertation uses body size and shape, entheseal expression and biomechanical properties of long bones to investigate: 1.) temporal patterns in postcranial dimensions, stature and body mass; 2.) regional differences between the northern and southern Chinese in body size and body/limb proportions; and 3.) variation in skeletal biomechanics and entheses in relation to subsistence strategy. The findings in this dissertation indicated that while the human skeletons studied were morphologically varied throughout Holocene China, they were, to some extent, correlated with climatic and environmental factors. Body size and shape and body/limb proportions corresponded with variation in temperature. Additionally, stature, body mass and entheseal expression were correlated with socio-political and cultural development. Nevertheless, entheseal expression unexpectedly did not show a straightforward relationship with subsistence strategy, in which is inconsistent with the findings of previous studies. Although the comparisons of biomechanical properties were not unequivocal, they suggest differences in mobility and mechanical loading between different populations and subsistence strategies. On the whole, the results suggested that variation in skeletal morphology of the Holocene Chinese follows the universal patterns on the one hand, while on the other, they were influenced by local environmental and behavioural factors.
2

Understanding plant water relations and root biomechanics for hydro-mechanical reinforcement of slopes

Boldrin, David January 2018 (has links)
Vegetation stabilises slopes via both mechanical reinforcement (through root anchorage) and hydrologic reinforcement (through transpiration-induced soil matric suction). However, relatively little is known about the effectiveness of different plant species in stabilising soil slopes via the two reinforcing mechanisms, and so decisions on species selection are seldom made with optimisation of slope reinforcement in mind. In this thesis, a comprehensive testing programme including laboratory, glasshouse and field experiments is designed and implemented, with the aim to quantify and investigate the transpiration-induced hydrologic reinforcement and root biomechanical properties during the early plant establishment of selected woody species, widespread under European temperate climate. Ten species native to Europe (Buxus sempervirens L.; Corylus avellana L.; Crataegus monogyna Jacq.; Cytisus scoparius (L.) Link; Euonymus europaeus L.; Ilex aquifolium L.; Ligustrum vulgare L.; Prunus spinosa L.; Salix viminalis L. and Ulex europaeus L.) were investigated in a glasshouse experiment to understand any relation of transpiration induced hydrologic reinforcement with above- and below-ground plant traits (e.g. specific leaf area; root length density). The ten species showed large differences in terms of water uptake, which translated to significant differences in matric suction and soil strength. Species with the largest water uptake increased soil strength more than ten times that in fallow soil. Specific leaf area, root length density and root:shoot ratio were best correlated with the induced hydrologic reinforcement provided by the ten tested species. These results supplied essential species information for designing the subsequent experiments. Based on the previous findings, three representative yet contrasting species (Corylus avellana, Ilex aquifolim and Ulex europaeus) were selected and planted in 1-m soil columns to investigate the effects of season (i.e. summer vs winter), plant functional type (i.e. deciduous vs evergreen) and soil depth on the magnitude and distribution of transpiration-induced matric suction and the associated soil strength gain. Evergreens could slowly induce matric suction and hence potentially stabilise soil during winter. However, there were very large differences between the tested evergreens (I. aquifolium and U. europaeus). Indeed, only U. europaeus provided matric suction and soil strength gain along the entire depth-profile because of its fast growth (above- and below-ground). A full-scale field experiment was also performed to provide ground-truth data on the extent of variation in hydrologic reinforcement among species, hence validating the glasshouse results obtained in the first two studies. The two-year field experiment yielded a similar ranking to the glasshouse experiments in terms of the species ability to rapidly develop matric suction and soil strength. In particular, the evergreen U. europaeus induced large matric suction (e.g. ≥ 70 kPa at 0.5 m depth) even during the early establishment period. Furthermore, this field research highlighted the greater (compared to other tested species) temporal effectiveness of U. europaeus, which was able to provide matric suction on the slope from early spring to late autumn. The greater ability of U. europaeus in inducing and preserving matric suction can be attributed to its large water uptake, which supports its fast growth, as well as to the notable interception loss provided by its canopy. Therefore, U. europaeus can represent a very suitable species for slope stabilisation under the temperate climate context. Root biomechanical properties, including tensile strength and Young's modulus, were investigated in the laboratory for the same ten species. The results highlighted a large variability in the tensile strength-diameter relations during the early stage establishment of plants, especially in thin roots with diameter ranging from 0.4 to 2.0 mm. The root tensile strength-diameter relationships highlighted three different trends. The common negative power relation between root tensile strength and diameter existed only for two out of the ten tested species (i.e. E. europaeus and U. europaeus). B. sempervirens, I. aquifolium and P. spinosa showed a slight increase in tensile strength with increasing root diameter. C. avellana, C. monogyna and L. vulgare consistently showed an initial increase in root tensile strength with increasing root diameter, reaching peak strength between 1.0 and 2.5 mm diameter. Beyond the peak strength, a reduction in strength was observed with increasing root dimeter. These bimodal trends might be partially explained by the differences in the development stage of root primary and secondary structures. Root moisture content can be one of the factors inducing the observed large variability in root tensile strength. Therefore, the last part of this thesis assessed the effects of root drying on the root biomechanical properties of U. europaeus. Root strength and stiffness showed an abrupt increase when root water content dropped below 0.5 g g-1. The strength increase can be explained by the reduction in root diameter and by changes in root properties induced by the root water potential drop. Moreover, root water loss and root strength gain were diameter-dependent because of the relatively larger evaporative surface per volume of thin roots.
3

Characterizations of Biomechanical Properties of Bones in Mammals

Wu, Yii-der 17 January 2007 (has links)
Pigs, mice and human beings are all vertebrate mammals. More than 90% of genomes in pigs and mice are the same as human beings. Experiment pigs and mice are with advantages in purebloods, small size, high reproductive capacity and short life cycle, etc. The tissue structure and metabolism of physiology in pig and mice are similar to human as well. Therefore, laboratory pigs and mice are often used to substitute human beings for biomedical engineering test. The research topics of this thesis are in the area of biomechanical properties of bones in mammal. The objectives of the study are to reveal the biomechanical properties of various types of bones and discuss its implication to human development. The entire thesis is divided into three parts. The first topic used micro-indentation test and FEM analysis for the determination of biomechanical properties of controlled cartilages in pigs. The second topic applied (a) three-point-bend failure test to study the age-related radius strength in mice, (b) tensile test to study the mechanical response of cranial sutures in mice, and (c) optical interferometry for 3D profile determination of mouse cranium. The third topic is for quantitative analysis of patterns in cranial sutures using DFT (Discrete Fourier Transform). The mechanism of diseases (such as osteoporosis, craniosynostosis, etc.) and the complexity of patterns in human cranial sutures in different age groups are discussed.
4

<strong>RAGE inhibition as a method to  improve tendon function in diabetic and healing murine models</strong>

Camila Ignacia Reyes Lauriani (16353375) 14 June 2023 (has links)
<p>  </p> <p>The disruption of homeostasis in tendon extracellular matrix and altered biomechanical properties lead to poor tendon healing, creating a significant clinical challenge for millions of diabetics. Furthermore, improving blood glucose levels doesn't normalize tendon properties in diabetics. Diabetes-related tendon complications are often associated with advanced glycation end products (AGEs) crosslinking with collagen. However, recent studies have found no evidence of higher collagen crosslinking in diabetics and no correlation between tendon AGE content and tensile strength. The interaction between serum AGEs and AGE receptors (RAGE) is a less explored mechanism of AGE-mediated effects. People with diabetes are more likely to accumulate AGEs in their serum as a result of hyperglycemia, the consumption of AGE-rich foods, and diminished kidney clearance of AGEs. In previous studies, advanced glycation end-products (AGEs) have been shown to inhibit cell proliferation and migration, both of which are critical to tendon healing. We hypothesized that serum AGEs and activation of RAGE represent a mechanism underlying impaired tendon properties with diabetes. The increasing serum AGE levels would impair tendon biomechanical properties and tendon healing, while inhibition of RAGE [Azeliragon (AZ)] would improve tendon mechanics.</p> <p>Db/db mice with naturally elevated serum AGEs and impaired tendon function were treated daily with a RAGE inhibitor [Azeliragon (AZ), n=9] or vehicle (n=10) for three weeks. Patellar tendon stiffness and modulus were greater (p<0.05) in mice receiving AZ (stiffness: 9.6±1.2 N/mm, modulus: 78.2±8.2 MPa) compared to vehicle (5.8±0.9 N/mm, modulus: 49.0±8.3 MPa). Maximum strain (vehicle: 0.9±0.1, AZ: 0.8±0.05) and toughness (vehicle: 6.1±1.4, AZ: 6.5±1.2 J·m−3) were not different between groups (p>0.05). Maximum stress tended to be greater in the AZ group (vehicle: 14.6±2.4, AZ: 23.3±2.9 N/mm2, p=0.156).</p> <p>Ten-week-old non-diabetic mice were assigned to receive daily injections of bovine serum albumin (BSA-only, n=6), BSA and AZ (BSA-AZ, n=5), 200 mg/ml glycated BSA (AGE-BSA, n=4), and AGE with AZ (AGE-AZ, n=6). A full-thickness, partial-width defect was created in both patellar tendons. Treatments were started one week before surgery and continued for three weeks after surgery. Three Tendon stiffness was lower in mice treated with AGEs (p<0.05, 10.8±1.4 N/mm) compared to BSA-only (17.6±1.3 N/mm). Further, tendon stiffness in AGE-treated mice given AZ was not different from AGE-BSA (p<0.05, 12.7±1.8 N/mm). Tendon modulus was lower in mice treated with AGEs (p<0.05, 28.0±7.0 MPa) compared to BSA-only (63.5±9.0 MPa). Additionally, modulus in AGE-treated mice given AZ was not different from AGE-BSA (p>0.05, 47.6±10.4 N/mm). </p> <p>We demonstrate that administering a RAGE inhibitor improves tendon properties in an established mouse model for type 2 diabetes. In healthy mice, serum AGE levels inhibit the recovery of tendon biomechanical properties after injury; RAGE inhibitors did not have an effect on mice given AGEs. Based on these data, we suggest elevated serum AGEs, as seen with diabetes, are associated with poor mechanical properties and delayed tendon healing.</p>
5

Intra-animal and Inter-animal Variations in the Biomechanical Properties of Tracheal Cartilage Rings

Karkhanis, Teja January 2015 (has links)
No description available.
6

Efeitos do ácido zoledrônico na rede de canais, no sistema lacunocanalicular e nas propriedades biomecânicas do osso cortical / Zoledronic acid effects in the cortical bone channels network, lacunocanalicular system and biomechanical properties

Rabelo, Gustavo Davi 04 June 2012 (has links)
O objetivo do presente trabalho foi avaliar a microarquitetura, caracterizando a rede de canais e o sistema lacunocanalicular, e também, as propriedades biomecânicas, do osso cortical de ratos Wistar tratados com Ácido Zoledrônico. Vinte e um ratos machos foram divididos da seguinte forma: 12 animais alocados no grupo de animais submetidos ao experimento no quarto mês de idade e 9 alocados no grupo de animais submetidos ao experimento no nono mês de idade. Dentro destes grupos, os mesmos foram divididos em grupos controle e teste, sendo que no grupo teste os animais receberam três doses, no esquema de 7,5 g/kg, semanalmente. Após o uso da medicação, três animais foram eutanasiados nos respectivos períodos, após a última dose: 14 dias, 42 dias e 75 dias. Todos os animais tiveram suas mandíbulas, tíbias e fêmures dissecados. As tíbias e mandíbulas foram descalcificadas e processadas para inclusão em parafina, enquanto que, os fêmures foram armazenados para os testes biomecânicos. Imagens histológicas digitalizadas, provenientes das mandíbulas e tíbias, foram analisadas utilizando o processo de segmentação interativa, acessando as características da microarquitetura da rede de canais. O processo de reconstrução tridimensional, para caracterização do sistema lacunocanalicular, foi realizado nos cortes seriados proveniente das tíbias. Os fêmures foram analisados com os ensaios de microdureza, compressão e flexão em três pontos. Os resultados revelaram que a microarquitetura da rede de canais não foi alterada nas mandíbulas, no entanto, nas tíbias, houve diferença significante apenas nos animais de 4 meses de idade, nos quesitos área dos canais (p 0.0031), desvio-padrão da área (p 0.0338), perímetro dos canais (p 0.0068), desvio padrão do perímetro (p 0.0297) e porcentagem de matriz (p 0.0235). Os testes biomecânicos revelaram resultados que indicavam uma melhora nas características analisadas, que foi correlacionada apenas com o aumento da idade e não com o uso do ácido zoledrônico. A visualização tridimensional possibilitou analisar a distribuição dos osteócitos e dos canais, caracterizando o sistema lacunocanalicular, e constatou-se que nos animais de 4 meses o uso da droga causou uma descontinuidade na estabilidade da distribuição dos osteócitos. Conclui-se que o ácido zoledrônico não interferiu na microarquitetura da rede de canais do osso cortical das mandíbulas, enquanto que nas tíbias, nos animais jovens, houve uma modificação na microarquitetura e no sistema lacunocanalicular, revelando uma topologia mais heterogênea quando comparadas ao grupo controle. As propriedades biomecânicas não sofreram alterações quanto ao uso da droga, sendo evidenciada melhora nos parâmetros analisados relacionada apenas ao aumento de idade nos animais. / The aim of this study was to evaluate the microstructure, characterizing the bone channels network and the lacunocanalicular system, also, the biomechanical properties of the cortical bone of Wistar rats treated with Zoledronic Acid. Twenty-one male rats were separated as follows: 4-month-old (12 animals) and 9 month-old (9 animals). For each age they were divided in control and test group, and the test group received a 7.5 g/kg dose of the drug, once a week, for 3 weeks. In the 4 month-old test group they were euthanized at 14, 42 and 75 days after the drug injection and in the 9-month-old test group they were sacrificed at 14 and 75 days after medication. All animals had their mandible, tibia and femur dissected, and then, the mandible and tibia were decalcified and embedded in paraffin, and, the femur were stored for mechanical tests. Histological images were analyzed through developed algorithms using the SCILAB mathematical environment, getting percentage of bone matrix, ROI areas, ROI perimeters, their standard deviations and Lacunarity, as well, the images were accessed and processed to tridimensional visualization, to characterize the lacunocanalicular system. The femurs were analyzed by microhardness, three point bending and compression testing. The results revealed that the bone channels network in the mandible was not affected by the drug, whereas the tibia in the 4-month-old animals revealed a statistical difference between control and test groups, with the test group revealing more heterogeneity in the channels topography, as seen in results of bone matrix (p=0.0235), ROI area (p=0.0031), ROI area standard-deviation (p=0.0338), ROI perimeter (p=0.0068) and ROI perimeter standard-deviation (p=0.0297). The biomechanical tests showed an increased in strength, and that this event was age-related and not depending on the use of the drug. The tridimensional visualization allowed to analyze the osteocyte distribution in relation to the channels position, characterizing the lacunocanalicular system, and, it was found that the 4-month-old animals the drug caused a discontinuity in the stability of osteocyte distribution. In conclusion, the zoledronic acid not interfere in the bone channels network in the cortical bone of the mandible, however, in the tibia of the young animals, theres been an alteration in bone channels network and in the lacunocanalicular system, revealing more heterogeneity in the topography in these animals. The biomechanical properties were not altered after the use of the drugs, and the increased in strength being age-related.
7

Estudo da correlação instrumental e sensorial de uma composição aromática aplicada na pele em função do ciclo menstrual / Study of instrumental and sensory correlation of a aromatic composition on the skin in function of mentrual cycle.

Costa, Claudia Silva Cortez Pereira da 19 December 2013 (has links)
A área de perfumaria no mundo vem se desenvolvendo a cada dia buscando maior conhecimento das matérias-primas aromáticas, desde suas reações, estabilidade até suas interações com o substrato onde é aplicado, sempre em busca do conhecimento de todas as variáveis que possam influenciar a relação perfume-substrato e a aceitação dos consumidores, medida por meio da avaliação sensorial. Apesar de muitos estudos sobre a relação perfume-pele, poucos envolveram a relação com ciclo menstrual. Neste estudo o objetivo foi correlacionar às análises sensorial e instrumental (medidas biomecânicas e cromatográficas), estudar as matérias-primas aromáticas em função do ciclo menstrual. O estudo envolveu indivíduos com idade entre 18-40 anos: 29 mulheres e 3 homens, estes usados como grupo controle. Cada voluntária teve 40 &#181;l da composição aromática Ciclo 1910 aplicado no antebraço, onde foram feitas as medidas biomecânicas (corneometria, sebumetria e TEWL) nos tempos inicial e 6h. Nos tempos inicial, 1.5h, 3h, 4,5h e 6h se auto-avaliaram sensorialmente a intensidade de perfume por meio de escala sensorial de magnitude rotulada (LMS) e foram coletados os compostos aromáticos liberados pela técnica de headspace e analisados por espectrometria com cromatografia a gás e detetor de massa (CGMS). Realizou-se também medidas biomecânicas de corneometria, sebumetria e TEWL interescapulares em 5 voluntárias nos tempos inicial e 6h para comparação. Os resultados obtidos foram que as fases do ciclo não interferiram nas variáveis biomecânicas (p>0,05) quando analisadas isoladamente. Para as medidas realizadas no antebraço, os índices de Corneometria (p<0,001) e TEWL (p: 0,011) na região tratada apresentou média maior que a do controle. A média dos índices de Corneometria e Sebumetria da região do antebraço tratada foi menor (p<0,001) que da região interescapular. Na análise cromatográfica não houve um padrão de resposta em diferentes fases do ciclo. As correlações entre a avaliação sensorial e instrumental (cromatografia e propriedades biomecânicas) não observaram nenhum nível de correlação (p>0,05). A Cromatografia (dados cromatográficos) foi maior na fase Folicular que nas fases Menstrual e Ovulatória (p=0,003), ao considerar como variável resposta em função do ciclo menstrual e da avaliação sensorial. Houve uma forte correlação positiva entre a análise sensorial e a avaliação na pele do homem (p<0,001). No entanto, o fator intrínseco do indivíduo Mulher influenciou na resposta, ocasionando grande variabilidade, porém percebeu-se claramente que os hormônios sexuais interferiram na resposta sensorial, cromatográfica e biomecânica da pele. / The perfumery in the world has been developed everyday bringing more knowledge about aromatic raw-materials, as from chemistry reactions, stability until their interactions with substrate where is applied, always looking for variables could influence in the relation perfume-substrate and consumer acceptability, measured by sensory evaluation. Despite a lot of studies were done on this subject, few involved effects as function of menstrual cycle. The aim of this study was to correlate sensory and instrumental analysis (biomechanical and chromatographic measurements), to study the olfactory profile of raw materials in function of menstrual cycle. The study involved people with 18-40 years old: 29 volunteers, three men, who were used as control group. Each volunteer had 40 &#181;l of perfume applied on forearm, where were done Biomechanical measurements (Corneometer, Sebumeter and TEWL) at initial and 6h, At time initial, 1.5h, 3h, 4.5h and 6h; they did self-sensory assessment in perfume intensity in own forearm using labeled magnitude scale (LMS) and also where aromatic compounds released were collected by headspace technique spectrometry and gas chromatography with mass detector (CGMS). In addition, it was done biomechanical measurements (Corneometer, Sebumeter and TEWL) on interscapular region at initial and 6h for comparing. Resulting that the phases of the cycle did not affect the biomechanical variables (p > 0.05) when analyzed individually. For measurements in the forearm, Corneometry index (p < 0.001) and TEWL (p=0.011) in the treated area were higher than the control. The average of the Sebumetry, Corneometry indexes of the forearm treated was lower (p <0.001) than the interscapular region. In the analysis of chromatographic, there was a standard response at different stages of the menstrual cycle, however the analysis by individual had no a pattern response to the release of aromatic compounds. The correlations between sensory and instrumental (chromatography and biomechanical properties) did not observe any correlation (p> 0.05). But when considering chromatography as the response variable as a function of the menstrual cycle and the sensory evaluation, the follicular phase was higher than the Menstrual and Ovulatory phase (p=0.003). There was a strong positive correlation between sensory analysis and evaluation on men skin (p<0.001). However, the intrinsic factor of the individual woman influenced the response, leading to large response variability; however, see clearly that sex hormones interfere in the sensory response, chromatographic and biomechanics of the skin.
8

Estudo da correlação instrumental e sensorial de uma composição aromática aplicada na pele em função do ciclo menstrual / Study of instrumental and sensory correlation of a aromatic composition on the skin in function of mentrual cycle.

Claudia Silva Cortez Pereira da Costa 19 December 2013 (has links)
A área de perfumaria no mundo vem se desenvolvendo a cada dia buscando maior conhecimento das matérias-primas aromáticas, desde suas reações, estabilidade até suas interações com o substrato onde é aplicado, sempre em busca do conhecimento de todas as variáveis que possam influenciar a relação perfume-substrato e a aceitação dos consumidores, medida por meio da avaliação sensorial. Apesar de muitos estudos sobre a relação perfume-pele, poucos envolveram a relação com ciclo menstrual. Neste estudo o objetivo foi correlacionar às análises sensorial e instrumental (medidas biomecânicas e cromatográficas), estudar as matérias-primas aromáticas em função do ciclo menstrual. O estudo envolveu indivíduos com idade entre 18-40 anos: 29 mulheres e 3 homens, estes usados como grupo controle. Cada voluntária teve 40 &#181;l da composição aromática Ciclo 1910 aplicado no antebraço, onde foram feitas as medidas biomecânicas (corneometria, sebumetria e TEWL) nos tempos inicial e 6h. Nos tempos inicial, 1.5h, 3h, 4,5h e 6h se auto-avaliaram sensorialmente a intensidade de perfume por meio de escala sensorial de magnitude rotulada (LMS) e foram coletados os compostos aromáticos liberados pela técnica de headspace e analisados por espectrometria com cromatografia a gás e detetor de massa (CGMS). Realizou-se também medidas biomecânicas de corneometria, sebumetria e TEWL interescapulares em 5 voluntárias nos tempos inicial e 6h para comparação. Os resultados obtidos foram que as fases do ciclo não interferiram nas variáveis biomecânicas (p>0,05) quando analisadas isoladamente. Para as medidas realizadas no antebraço, os índices de Corneometria (p<0,001) e TEWL (p: 0,011) na região tratada apresentou média maior que a do controle. A média dos índices de Corneometria e Sebumetria da região do antebraço tratada foi menor (p<0,001) que da região interescapular. Na análise cromatográfica não houve um padrão de resposta em diferentes fases do ciclo. As correlações entre a avaliação sensorial e instrumental (cromatografia e propriedades biomecânicas) não observaram nenhum nível de correlação (p>0,05). A Cromatografia (dados cromatográficos) foi maior na fase Folicular que nas fases Menstrual e Ovulatória (p=0,003), ao considerar como variável resposta em função do ciclo menstrual e da avaliação sensorial. Houve uma forte correlação positiva entre a análise sensorial e a avaliação na pele do homem (p<0,001). No entanto, o fator intrínseco do indivíduo Mulher influenciou na resposta, ocasionando grande variabilidade, porém percebeu-se claramente que os hormônios sexuais interferiram na resposta sensorial, cromatográfica e biomecânica da pele. / The perfumery in the world has been developed everyday bringing more knowledge about aromatic raw-materials, as from chemistry reactions, stability until their interactions with substrate where is applied, always looking for variables could influence in the relation perfume-substrate and consumer acceptability, measured by sensory evaluation. Despite a lot of studies were done on this subject, few involved effects as function of menstrual cycle. The aim of this study was to correlate sensory and instrumental analysis (biomechanical and chromatographic measurements), to study the olfactory profile of raw materials in function of menstrual cycle. The study involved people with 18-40 years old: 29 volunteers, three men, who were used as control group. Each volunteer had 40 &#181;l of perfume applied on forearm, where were done Biomechanical measurements (Corneometer, Sebumeter and TEWL) at initial and 6h, At time initial, 1.5h, 3h, 4.5h and 6h; they did self-sensory assessment in perfume intensity in own forearm using labeled magnitude scale (LMS) and also where aromatic compounds released were collected by headspace technique spectrometry and gas chromatography with mass detector (CGMS). In addition, it was done biomechanical measurements (Corneometer, Sebumeter and TEWL) on interscapular region at initial and 6h for comparing. Resulting that the phases of the cycle did not affect the biomechanical variables (p > 0.05) when analyzed individually. For measurements in the forearm, Corneometry index (p < 0.001) and TEWL (p=0.011) in the treated area were higher than the control. The average of the Sebumetry, Corneometry indexes of the forearm treated was lower (p <0.001) than the interscapular region. In the analysis of chromatographic, there was a standard response at different stages of the menstrual cycle, however the analysis by individual had no a pattern response to the release of aromatic compounds. The correlations between sensory and instrumental (chromatography and biomechanical properties) did not observe any correlation (p> 0.05). But when considering chromatography as the response variable as a function of the menstrual cycle and the sensory evaluation, the follicular phase was higher than the Menstrual and Ovulatory phase (p=0.003). There was a strong positive correlation between sensory analysis and evaluation on men skin (p<0.001). However, the intrinsic factor of the individual woman influenced the response, leading to large response variability; however, see clearly that sex hormones interfere in the sensory response, chromatographic and biomechanics of the skin.
9

Efeitos do ácido zoledrônico na rede de canais, no sistema lacunocanalicular e nas propriedades biomecânicas do osso cortical / Zoledronic acid effects in the cortical bone channels network, lacunocanalicular system and biomechanical properties

Gustavo Davi Rabelo 04 June 2012 (has links)
O objetivo do presente trabalho foi avaliar a microarquitetura, caracterizando a rede de canais e o sistema lacunocanalicular, e também, as propriedades biomecânicas, do osso cortical de ratos Wistar tratados com Ácido Zoledrônico. Vinte e um ratos machos foram divididos da seguinte forma: 12 animais alocados no grupo de animais submetidos ao experimento no quarto mês de idade e 9 alocados no grupo de animais submetidos ao experimento no nono mês de idade. Dentro destes grupos, os mesmos foram divididos em grupos controle e teste, sendo que no grupo teste os animais receberam três doses, no esquema de 7,5 g/kg, semanalmente. Após o uso da medicação, três animais foram eutanasiados nos respectivos períodos, após a última dose: 14 dias, 42 dias e 75 dias. Todos os animais tiveram suas mandíbulas, tíbias e fêmures dissecados. As tíbias e mandíbulas foram descalcificadas e processadas para inclusão em parafina, enquanto que, os fêmures foram armazenados para os testes biomecânicos. Imagens histológicas digitalizadas, provenientes das mandíbulas e tíbias, foram analisadas utilizando o processo de segmentação interativa, acessando as características da microarquitetura da rede de canais. O processo de reconstrução tridimensional, para caracterização do sistema lacunocanalicular, foi realizado nos cortes seriados proveniente das tíbias. Os fêmures foram analisados com os ensaios de microdureza, compressão e flexão em três pontos. Os resultados revelaram que a microarquitetura da rede de canais não foi alterada nas mandíbulas, no entanto, nas tíbias, houve diferença significante apenas nos animais de 4 meses de idade, nos quesitos área dos canais (p 0.0031), desvio-padrão da área (p 0.0338), perímetro dos canais (p 0.0068), desvio padrão do perímetro (p 0.0297) e porcentagem de matriz (p 0.0235). Os testes biomecânicos revelaram resultados que indicavam uma melhora nas características analisadas, que foi correlacionada apenas com o aumento da idade e não com o uso do ácido zoledrônico. A visualização tridimensional possibilitou analisar a distribuição dos osteócitos e dos canais, caracterizando o sistema lacunocanalicular, e constatou-se que nos animais de 4 meses o uso da droga causou uma descontinuidade na estabilidade da distribuição dos osteócitos. Conclui-se que o ácido zoledrônico não interferiu na microarquitetura da rede de canais do osso cortical das mandíbulas, enquanto que nas tíbias, nos animais jovens, houve uma modificação na microarquitetura e no sistema lacunocanalicular, revelando uma topologia mais heterogênea quando comparadas ao grupo controle. As propriedades biomecânicas não sofreram alterações quanto ao uso da droga, sendo evidenciada melhora nos parâmetros analisados relacionada apenas ao aumento de idade nos animais. / The aim of this study was to evaluate the microstructure, characterizing the bone channels network and the lacunocanalicular system, also, the biomechanical properties of the cortical bone of Wistar rats treated with Zoledronic Acid. Twenty-one male rats were separated as follows: 4-month-old (12 animals) and 9 month-old (9 animals). For each age they were divided in control and test group, and the test group received a 7.5 g/kg dose of the drug, once a week, for 3 weeks. In the 4 month-old test group they were euthanized at 14, 42 and 75 days after the drug injection and in the 9-month-old test group they were sacrificed at 14 and 75 days after medication. All animals had their mandible, tibia and femur dissected, and then, the mandible and tibia were decalcified and embedded in paraffin, and, the femur were stored for mechanical tests. Histological images were analyzed through developed algorithms using the SCILAB mathematical environment, getting percentage of bone matrix, ROI areas, ROI perimeters, their standard deviations and Lacunarity, as well, the images were accessed and processed to tridimensional visualization, to characterize the lacunocanalicular system. The femurs were analyzed by microhardness, three point bending and compression testing. The results revealed that the bone channels network in the mandible was not affected by the drug, whereas the tibia in the 4-month-old animals revealed a statistical difference between control and test groups, with the test group revealing more heterogeneity in the channels topography, as seen in results of bone matrix (p=0.0235), ROI area (p=0.0031), ROI area standard-deviation (p=0.0338), ROI perimeter (p=0.0068) and ROI perimeter standard-deviation (p=0.0297). The biomechanical tests showed an increased in strength, and that this event was age-related and not depending on the use of the drug. The tridimensional visualization allowed to analyze the osteocyte distribution in relation to the channels position, characterizing the lacunocanalicular system, and, it was found that the 4-month-old animals the drug caused a discontinuity in the stability of osteocyte distribution. In conclusion, the zoledronic acid not interfere in the bone channels network in the cortical bone of the mandible, however, in the tibia of the young animals, theres been an alteration in bone channels network and in the lacunocanalicular system, revealing more heterogeneity in the topography in these animals. The biomechanical properties were not altered after the use of the drugs, and the increased in strength being age-related.
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Soft Tissue Aspects of the Shoulder Joint

Khoschnau, Shwan January 2012 (has links)
The aim of this thesis was to study different aspects of the soft tissues of the shoulder joint. The variation in the quality of the tendons and ligaments can be explained by genetic factors. To test the hypothesis that collagen 1 α1 Sp1 polymorphism is related to the occurrence of cruciate ligament ruptures and shoulder dislocations, a total of 358 patients (233 patients with cruciate ligament ruptures and 126 with shoulder dislocations) were included in the study. We found a decreased risk of these injuries associated with collagen type 1 α1 Sp1 polymorphism. To study the mechanical properties of a better type of fixation of soft tissue to bone, 10 skeletally mature New Zealand white rabbits were operated bilaterally on the knees. The medial collateral ligaments were fixed by two types of plates one with a flat undersurface and the other with a pegged undersurface. After 4 weeks the force at failure, stiffness and energy uptake was almost double in the knees operated with the pegged plates. The prevalence and dysfunction of rotator cuff tears was investigated in 106 subjects who had never sought for their shoulder complaints, using Constant score, ultrasound and plain x-ray. The prevalence of full-thickness cuff tears was 30% (21% of all shoulders). The Constant score was lower in subjects with full-thickness tears. Partial-thickness tears and acromioclavicular joint osteoarthritis had no impact on shoulder complaints or Constant score. The subacromial index was lower for shoulders with full-thickness tears. Forty-eight patients with median age 56 years underwent subacromial decompression with or without acromioclavicular joint resection, investigated with MRI pre- and 3 months postoperatively. The Constant score and subjective shoulder value were measured preoperatively and at 3 and 6 months after surgery and even 2 years for subjective shoulder value. Two raters investigated the MRI. The results showed poor inter-rater reliability for MRI. However, both Constant score and subjective shoulder value improved over time. MRI is not a reliable method to study the capsular reaction after subacromial decompression due to high subjectivity of the radiologists.

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