Buscando analisar a natureza da sociedade na qual vivemos, que passa a ter uma dimensão virtual proporcionada por jogos massivos multijogadores de interpretação de personagens baseados na Web, ou Massively Multiplayer On-line Role Playing Games – MMORPGs -, recorremos à teoria de Axel Honneth. O autor identifica o surgimento de um individualismo da auto-realização em sociedades capitalistas modernas, em que os indivíduos demandam condições autônomas de busca por auto-realização para alcançar o que compreendem por “vida boa”. Esse trabalho analisa os motivos que levam os jogadores a optar por participar da “sociedade virtual” dos jogos, partindo da hipótese de que o ambiente social que estes proporcionam possibilita a construção da auto-realização dos jogadores de forma complementar ao ambiente social ao qual o indivíduo pertence de carne-e-osso. Os jogos MMORPGs estariam assim complementando as necessidades individuais de realização social e os ambientes sociais “virtuais“ sendo, portanto, concretos em suas contribuições para tais demandas individuais. O que explica a opção dos jogadores por vivenciar suas relações sociais dentro do jogo. Para investigar a veracidade dessa hipótese, realizou-se uma etnografia virtual no ambiente do jogo Tibia e utilizou-se a técnica de observação participante que nomeamos “Jogando”: assistindo, lendo, escrevendo e participando. Os dados foram coletados através de conversas informais com mais de quinhentos personagens por um período de dezessete meses, num total aproximado de quatro mil horas. Foram analisados conforme a particularidade de cada tipo de relação desenvolvida pelos jogadores: amorosas, jurídicas e de valoração social. Essa pesquisa contribui para a compreensão de diversos fenômenos sociais relacionados a esse tipo de jogo e para auxiliar os diferentes públicos - formadores de opinião, familiares de jogadores, jogadores em potencial, instituições de ensino - a avaliar o ato de jogar. Os dados confirmam nossa hipótese e possibilitam a elaboração de perguntas sobre fenômenos que se reproduzem no ambiente virtual e contradizem os anseios daqueles que acreditam que “um outro mundo é possível”. / In order to analyze the nature of the society we live today, which has a new virtual dimension possible by the Massively Multiplayer On-line Role Playing Games – MMORPGs -, we requested Axel Honneth’s theory. The author identifies the arising of an individualism of self-realization in modern capitalist societies, in which the individuals demand autonomous conditions of search for self-realization to reach what they understand as “good life”. This work analyzes the motives that lead the players to opt to participate in the “virtual society” of the games, starting from the hypothesis that the social environment that these games provide enables the construction of the players’ self-realization in a complementary way to the social environment which the individual belongs in flesh and blood. The MMORPGs are so complementing the individuals’ needs of social realization, and the “virtual” social environments being concrete in their contributions to such individuals’ demands. What explains the players’ option to experience their social relations inside the game. To investigate the veracity of this hypothesis a virtual ethnography was carried out in the Tibia game environment and the technique of participative observation was utilized, which we named “Playing”: watching, reading, writing and participating. The data were collected through informal conversations with more than five hundred characters for a period of seventeen months, in a total of approximately four thousand hours. They were analyzed by the particularity of each type of relation developed by the players: loving, legal and social appraisal. This research contributes to the comprehension of diverse social phenomena related to this kind of game and to assist the different publics – opinion creators, relative of players, potential players, and education institutions – to evaluate the act of to play. The data confirm our hypothesis and make possible the elaboration of questions about phenomena that are reproduced in the virtual environment and contradict the yearnings of those who believe that “another world is possible”.

Buscando analisar a natureza da sociedade na qual vivemos, que passa a ter uma dimensão virtual proporcionada por jogos massivos multijogadores de interpretação de personagens baseados na Web, ou Massively Multiplayer On-line Role Playing Games – MMORPGs -, recorremos à teoria de Axel Honneth. O autor identifica o surgimento de um individualismo da auto-realização em sociedades capitalistas modernas, em que os indivíduos demandam condições autônomas de busca por auto-realização para alcançar o que compreendem por “vida boa”. Esse trabalho analisa os motivos que levam os jogadores a optar por participar da “sociedade virtual” dos jogos, partindo da hipótese de que o ambiente social que estes proporcionam possibilita a construção da auto-realização dos jogadores de forma complementar ao ambiente social ao qual o indivíduo pertence de carne-e-osso. Os jogos MMORPGs estariam assim complementando as necessidades individuais de realização social e os ambientes sociais “virtuais“ sendo, portanto, concretos em suas contribuições para tais demandas individuais. O que explica a opção dos jogadores por vivenciar suas relações sociais dentro do jogo. Para investigar a veracidade dessa hipótese, realizou-se uma etnografia virtual no ambiente do jogo Tibia e utilizou-se a técnica de observação participante que nomeamos “Jogando”: assistindo, lendo, escrevendo e participando. Os dados foram coletados através de conversas informais com mais de quinhentos personagens por um período de dezessete meses, num total aproximado de quatro mil horas. Foram analisados conforme a particularidade de cada tipo de relação desenvolvida pelos jogadores: amorosas, jurídicas e de valoração social. Essa pesquisa contribui para a compreensão de diversos fenômenos sociais relacionados a esse tipo de jogo e para auxiliar os diferentes públicos - formadores de opinião, familiares de jogadores, jogadores em potencial, instituições de ensino - a avaliar o ato de jogar. Os dados confirmam nossa hipótese e possibilitam a elaboração de perguntas sobre fenômenos que se reproduzem no ambiente virtual e contradizem os anseios daqueles que acreditam que “um outro mundo é possível”. / In order to analyze the nature of the society we live today, which has a new virtual dimension possible by the Massively Multiplayer On-line Role Playing Games – MMORPGs -, we requested Axel Honneth’s theory. The author identifies the arising of an individualism of self-realization in modern capitalist societies, in which the individuals demand autonomous conditions of search for self-realization to reach what they understand as “good life”. This work analyzes the motives that lead the players to opt to participate in the “virtual society” of the games, starting from the hypothesis that the social environment that these games provide enables the construction of the players’ self-realization in a complementary way to the social environment which the individual belongs in flesh and blood. The MMORPGs are so complementing the individuals’ needs of social realization, and the “virtual” social environments being concrete in their contributions to such individuals’ demands. What explains the players’ option to experience their social relations inside the game. To investigate the veracity of this hypothesis a virtual ethnography was carried out in the Tibia game environment and the technique of participative observation was utilized, which we named “Playing”: watching, reading, writing and participating. The data were collected through informal conversations with more than five hundred characters for a period of seventeen months, in a total of approximately four thousand hours. They were analyzed by the particularity of each type of relation developed by the players: loving, legal and social appraisal. This research contributes to the comprehension of diverse social phenomena related to this kind of game and to assist the different publics – opinion creators, relative of players, potential players, and education institutions – to evaluate the act of to play. The data confirm our hypothesis and make possible the elaboration of questions about phenomena that are reproduced in the virtual environment and contradict the yearnings of those who believe that “another world is possible”.

Locomotion is one of the most important qualities of man and has always been associated with survival, foraging ans subsistence. During the course of evolution, men and women developed some form of gender specialization which resulted in different level of mobility between the sexes. Throughout history, the types of subsistence have changed and the degree of sedentism has increased. However, despite all the changes in subsistence, gender specialization and bone robusticity sexual dimorphism in the robusticity of the lower limb bones remained surprisingly stable. Is it possible that women load lower limb bones differenty than men (e.i. due to different body proportions)? The aim of this work is to determine wheter there is sexual dimorphism between the sexes of the recent living population in the cross-sectional properties of the tibia and in the load on the tibia during running. In this work we used images of the tibia from magnetic resonance imaging and kinematic and kinetic data during the run of 20 probands. By using musculoskeletal modeling we estimated the bending moment acting at 50 % of the tibial length as well as the angle of action of this moment. After adjusting for size, no significant difference was found in the results of cross-sectional geometry of the bone in any of the monitored...

External fixators are used in a treatment of complicated fractures and their properties have a crucial impact on treatment quality. Therefore, this thesis is concerned with a biomechanical study of a bone (tibia) with applied external fixators via strain-stress analysis and their comparison with a state of tibia without applied fixator (physiological state). After creating the volume models of geometry of tibia and seven variants of external axial fixators, the corresponding finite element method (FEM) models are created. The analysis of tibia without applied fixator and tibia with all studied fixators is made for three states of load which correspond to characteristic load states during the first stage of treatment. The strain-stress analysis is made using finite element method. Furthermore, the methods of displacement and rotation evaluation during loading are proposed. One can conclude from the results of the strain-stress analysis how the different variants of fixators prevent the displacement and rotation of the bone during the different load states and the comparisons with the physiological state of bone are made. Bone tissue loading is determined from the distribution and the values of the first and the third principal stresses. Finally, comparing the results of all variants the influence of the fixator length, the gap between the fixation elements near the fracture, the number and the setting of the fixation elements on the fixation properties is analysed.

The mechanical loading affects the long bone cross-section geometry (CSG). The aim of this thesis was to examine experimentally the relationship between the locomotory parameters and cross-sectional properties of long bones, and to test some partial knowledge of the bone mechanical adaptation. Two groups of B6CBA mice were examined: (a) Lurcher type (model of olivocerebellar degeneration; n = 10) and (b) control (normal mice; n = 10). We analyzed the motor characteristics and the bone cross-sectional geometric properties. The motor tests included the test of spontaneous motor activity (Open field), strength properties (horizontal bar) and motor coordination (rotarod). Cross-sections were taken in 50 % of the left tibia biomechanical length and further processed for fluorescence confocal microscopy. We analyzed the biomechanical properties of cortical bone cross-sections (software ImageJ). There were nonsignificant differences in CSG parameters (TA, CA, Imax, Imin, J, Imax/Imin) between Lurcher and control mice. The results did not support our assumption about the effect of motor disorder on CSG properties. We did not demonstrate the effect of local factors on the bone biomechanical adaptation. The results of this thesis may be useful to find new testing possibilities of cortical bone in...

Topology-based optimization techniques and lattice structures are powerful ways to accomplish lightweight components with enhanced mechanical performance. Recent developments in additive manufacturing (AM) have led the way to extraordinary opportunities in realizing complex designs that are derived from topology and lattice-based structural optimization. The main aim of this work is to give a contribution, in the integration between structural optimization techniques and AM, by proposing a setup of a proper methodology for rapid development of optimized medical implants addressing oseeointegration and minimization of stress shielding related problems. The validity of the proposed methodology for a proof of concept was demonstrated in two real-world case studies: a tibia intramedullary implant and a shoulder hemi prosthetics for two bone cancer patients. The optimization was achieved using topology optimization and replacement of solid volumes by lattice structures. Samples of three lattice unit cell configurations were designed, fabricated, mechanically tested, and compared to select the most proper configuration for the shoulder hemi prosthesis. Weight reductions of 30% and 15% were achieved from the optimization of the initial design of the tibia intramedullary implant and the shoulder hemiprosthesis respectively compared to initial designs. Prototypes were fabricated using selective laser melting (SLM) and direct light processing (DLP) technologies. Validation analysis was performed using finite element analysis and compressive mechanical testing. Future work recommendations are provided for further development and improvement of the work presented in this thesis.

The aim of this study was to detect and describe the trends in shape variability of proximal and distal human tibia related to sex, age, social status and time period. The variability of its shape and form was analysed first in an early medieval sample, then in two modern populations, an early 20th century sample and the contemporary Czech population. Finally, data from the whole studied time span were analysed. The initial raw data were acquired by optical scanning and computed tomography (CT) scanning of the lower limbs; the three-dimensional bone surfaces of the contemporary tibias were segmented from the clinical CT scan sequences. Geometric morphometrics and multivariate statistical methods were applied to study the variations in shape and form quantitatively. Proximal and distal tibias were evaluated independently, and the potential influence of sex, age at death and time period were investigated. In the early medieval population, we also explored the relationship between tibial morphology and presumed social status derived from the respective grave location within the settlement. Because traditional morphometric analysis revealed statistically significant sex differences in the parameters of both tibial extremities (e.g., Steyn and Işcan, 1997; Šlaus et al., 2013), we thus assumed the...

Introdução: A tomografia computadorizada periférica quantitativa de alta resolução (HR-pQCT) é um método diagnóstico que avalia microarquitetura óssea e estima resistência óssea por análise de elemento finito, facilitando a compreensão da fisiopatologia das fraturas. Objetivo: Avaliar associação de fraturas vertebrais moderadas e graves com parâmetros obtidos na HR-pQCT, escore trabecular ósseo (TBS) e densidade mineral óssea areal em idosos da comunidade. Métodos: Foram recrutados 276 idosos da coorte SPAH. Dados clínicos foram obtidos a partir de um questionário específico. A fratura vertebral (FV) foi avaliada por DXA-VFA utilizando-se o método semiquantitativo de Genant. HR-pQCT e DXA foram realizados no mesmo dia da coleta de sangue. O modelo de regressão logística foi realizado para verificar quais fatores foram associados de forma independente com a fratura vertebral moderada e grave. Resultados: Na tíbia, mulheres com FV moderada/grave apresentaram menor densidade mineral óssea volumétrica, menor número de trabéculas, menores valores dos parâmetros de resistência óssea e maior separação trabecular; e os homens apresentaram menor número de trabéculas, menor parâmetro de resistência óssea e maior separação trabecular. No rádio, as mulheres com FV moderada/grave tinham menor densidade mineral óssea volumétrica, espessura trabecular e cortical e menor valor do parâmetro de análise do elemento finito; e os homens tinham menor densidade mineral óssea volumétrica trabecular e menor valor de parâmetro de análise do elemento finito. Não foram observadas diferenças no TBS em ambos os sexos. A análise de regressão logística revelou que uma menor densidade mineral óssea volumétrica trabecular na tíbia em mulheres (OR: 0,980, 95% CI: 0,963-0,997, p = 0,022) e uma menor densidade mineral óssea areal do colo femoral e fêmur total em homens (OR: 0,002, IC 95%: 0-0,607, p = 0,033 e OR: 0,003, IC 95%: 0-0,623, p = 0,033) foram independentemente associados com FV moderada/grave. Conclusão: As imagens da HR-pQCT detectaram diferenças na microarquitetura óssea em mulheres idosas com FV moderada/grave independente de densidade mineral óssea areal e TBS por DXA; e HRpQCT pode ser uma ferramenta útil para avaliar o risco de fratura. Diferentemente, nos homens, a densidade mineral óssea areal do fêmur foi associada à FV moderada/grave; e a DXA continua sendo uma ferramenta importante para predizer a FV / Background: Many vertebral fractures (VF) occur in individuals classified by DXA as low risk for fragility fractures. Thus, the aim of this study was to verify the association between VF and peripheral bone microarchitecture and strength parameters using also high-resolution peripheral quantitative computed tomography (HR-pQCT) and axial bone microarchitecture by trabecular bone score (TBS). Study design: Cross-sectional study of 276 subjects aged >=65 years from SPAH cohort. Methods: Lateral scans of spine obtained from Vertebral Fracture Assessment by DXA were analyzed to assess VF. HR-pQCT was performed at radius and tibia. TBS was performed using DXA. Results: At tibia, women with Moderate/severe VF had lower volumetric bone density (vBMD), trabecular number (Tb.N), strength parameters and higher trabecular separation (Tb.Sp); and men had lower Tb.N, strength parameters and higher Tb.Sp. At radius, women with moderate/severe VF had lower v.BMD, trabecular and cortical thickness and strength parameters; and men had lower trabecular v.BMD and strength parameters. No differences were observed in TBS in both genders. Logistic regression analysis revealed that lower trabecular vBMD at tibia in women (OR: 0.980, 95%CI: 0.963-0.997, p = 0.022) and lower femoral neck aBMD and total hip in men (OR: 0.002, 95%CI: 0-0.607, p = 0.033 and OR: 0,003, IC 95%: 0-0,623, p = 0,033) were independently associated with VF. Conclusion: HR-pQCT images detected differences on bone microstructure in older women with moderate/severe VF independent of aBMD and TBS by DXA and HR-pQCT could be useful tool to assess fracture risk. Differently, in men femoral aBMD was associated with moderate/severe VF and DXA continue an important tool for predicting VF

A Pseudoartrose Congênita da Tíbia (PCT) é uma das doenças mais desafiantes da ortopedia pediátrica pela dificuldade em obter a união óssea e, quando esta ocorre, em mantê-la. É uma doença muito rara, difícil de tratar devido à sua falta de conhecimento sobre a patogênese. As Células estromais mesenquimais multipotentes (CMM) podem desempenhar um papel na patogênese do PCT, possivelmente devido à falha da diferenciação osteogênica. O estudo das CMM pode ajudar a compreender a patogênese da doença e desenvolver novas estratégias terapêuticas baseados no uso desta célula no futuro próximo. Frente ao exposto, este trabalho teve como objetivo a análise das características biológicas das CMM isoladas de diferentes regiões anatômicas de medula óssea de pacientes com PCT. Para isto, amostras de medula óssea foram coletas a partir de locais afetados e não afetadas pela doença: Crista ilíaca do membro não afetada (CINA), crista ilíaca do membro afetada (CIA), tíbia não afetada (TNA), e tíbia afetada (TA). O numero de pacientes incluídos no estudo foi três: PCT1, PCT2 e PCT3. Os resultados mostraram que todas as células isoladas de pacientes com PCT apresentavam características compatíveis com as CMM. A taxa de formação de unidades formadoras de colônias das células da TA tanto no PCT2 quanto no PCT3 foi significativamente menor em relação às células da TNA e CINA respectivamente (p<0.05). A quantidade de células positivas para o marcador CD146 foi menor nas células da TA do PCT1 e PCT2, A análise estatística mostrou que não há uma diferença significativa. Este marcador esta relacionado com a capacidade multipotente e formação óssea in vivo. No PCT1 observou-se que formação de matriz mineralizada das CMM isoladas da CIA foi significativamente maior em relação a TA. Além disso, as células da TA do PCT1 observou-se um uma secreção significativa de alguns citocinas envolvidas no processo de formação óssea, como CCL2, CCL3, CCL4, TNA-alfa, PDGF-BB, e GM-CSF. A alteração destas citocinas pode levar a situações complicadas como o caso de não consolidação óssea. Com os resultados obtidos, se há demonstrado que as CMM da tíbia afetada tenta formar osso, mas no local da lesão é insuficiente, por tal motivo é preciso realizar estudos focados no mecanismo molecular. / Congenital pseudoarthrosis of the tibia (CPT) is one of the most challenging orthopedic diseases because of the difficulty in obtaining bone union and, when it happens, in maintaining it. It is a rare disease, difficult-to-treat due to the lack of knowledge about to pathogenesis. Multipotent mesenchymal stromal cells (MSC) may play a role in the pathogenesis of PCT, possibly due to a failure in the osteogenic differentiation. Studying these cells can help to better understand the pathogenesis of the disease and develop new therapeutic strategies based on the use of MSC in the near future. In view of the above, this work had the objective of analyzing the biological characteristics of CMM isolated from different anatomic regions of bone marrow of patients with PCT. For this, bone marrow samples were collected from sites affected and unaffected by the disease: unaffected limb iliac crest (CINA), affected limb iliac crest (CIA), unaffected tibia (TNA), and affected tibia (TA). The number of patients included in the study was three: PCT1, PCT2 and PCT3. The results showed that all cells isolated from PCT patients had characteristics compatible with CMM. The rate of formation of colonyforming units of TA cells in both PCT2 and PCT3 was significantly lower in TNA and CINA cells respectively (p <0.05). The amount of cells positive for the CD146 marker was lower in the TA cells of PCT1 and PCT2. Statistical analysis showed no significant difference. This marker is related to the multipotent capacity and bone formation in vivo. In PCT1 it was observed that the formation of mineralized matrix of CMCs isolated from CIA was significantly higher in relation to AT. In addition, PCT1 TA cells showed a significant secretion of some cytokines involved in the bone formation process, such as CCL2, CCL3, CCL4, TNA-alpha, PDGF-BB, and GM-CSF. The alteration of these cytokines can lead to complicated situations such as the case of non-consolidation of bone. With the results obtained, if the CMM of the affected tibia has been shown to try to form bone, but at the site of the lesion is insufficient, it is necessary to carry out studies focused on the molecular mechanism.

A Pseudoartrose Congênita da Tíbia (PCT) é uma das doenças mais desafiantes da ortopedia pediátrica pela dificuldade em obter a união óssea e, quando esta ocorre, em mantê-la. É uma doença muito rara, difícil de tratar devido à sua falta de conhecimento sobre a patogênese. As Células estromais mesenquimais multipotentes (CMM) podem desempenhar um papel na patogênese do PCT, possivelmente devido à falha da diferenciação osteogênica. O estudo das CMM pode ajudar a compreender a patogênese da doença e desenvolver novas estratégias terapêuticas baseados no uso desta célula no futuro próximo. Frente ao exposto, este trabalho teve como objetivo a análise das características biológicas das CMM isoladas de diferentes regiões anatômicas de medula óssea de pacientes com PCT. Para isto, amostras de medula óssea foram coletas a partir de locais afetados e não afetadas pela doença: Crista ilíaca do membro não afetada (CINA), crista ilíaca do membro afetada (CIA), tíbia não afetada (TNA), e tíbia afetada (TA). O numero de pacientes incluídos no estudo foi três: PCT1, PCT2 e PCT3. Os resultados mostraram que todas as células isoladas de pacientes com PCT apresentavam características compatíveis com as CMM. A taxa de formação de unidades formadoras de colônias das células da TA tanto no PCT2 quanto no PCT3 foi significativamente menor em relação às células da TNA e CINA respectivamente (p<0.05). A quantidade de células positivas para o marcador CD146 foi menor nas células da TA do PCT1 e PCT2, A análise estatística mostrou que não há uma diferença significativa. Este marcador esta relacionado com a capacidade multipotente e formação óssea in vivo. No PCT1 observou-se que formação de matriz mineralizada das CMM isoladas da CIA foi significativamente maior em relação a TA. Além disso, as células da TA do PCT1 observou-se um uma secreção significativa de alguns citocinas envolvidas no processo de formação óssea, como CCL2, CCL3, CCL4, TNA-alfa, PDGF-BB, e GM-CSF. A alteração destas citocinas pode levar a situações complicadas como o caso de não consolidação óssea. Com os resultados obtidos, se há demonstrado que as CMM da tíbia afetada tenta formar osso, mas no local da lesão é insuficiente, por tal motivo é preciso realizar estudos focados no mecanismo molecular. / Congenital pseudoarthrosis of the tibia (CPT) is one of the most challenging orthopedic diseases because of the difficulty in obtaining bone union and, when it happens, in maintaining it. It is a rare disease, difficult-to-treat due to the lack of knowledge about to pathogenesis. Multipotent mesenchymal stromal cells (MSC) may play a role in the pathogenesis of PCT, possibly due to a failure in the osteogenic differentiation. Studying these cells can help to better understand the pathogenesis of the disease and develop new therapeutic strategies based on the use of MSC in the near future. In view of the above, this work had the objective of analyzing the biological characteristics of CMM isolated from different anatomic regions of bone marrow of patients with PCT. For this, bone marrow samples were collected from sites affected and unaffected by the disease: unaffected limb iliac crest (CINA), affected limb iliac crest (CIA), unaffected tibia (TNA), and affected tibia (TA). The number of patients included in the study was three: PCT1, PCT2 and PCT3. The results showed that all cells isolated from PCT patients had characteristics compatible with CMM. The rate of formation of colonyforming units of TA cells in both PCT2 and PCT3 was significantly lower in TNA and CINA cells respectively (p <0.05). The amount of cells positive for the CD146 marker was lower in the TA cells of PCT1 and PCT2. Statistical analysis showed no significant difference. This marker is related to the multipotent capacity and bone formation in vivo. In PCT1 it was observed that the formation of mineralized matrix of CMCs isolated from CIA was significantly higher in relation to AT. In addition, PCT1 TA cells showed a significant secretion of some cytokines involved in the bone formation process, such as CCL2, CCL3, CCL4, TNA-alpha, PDGF-BB, and GM-CSF. The alteration of these cytokines can lead to complicated situations such as the case of non-consolidation of bone. With the results obtained, if the CMM of the affected tibia has been shown to try to form bone, but at the site of the lesion is insufficient, it is necessary to carry out studies focused on the molecular mechanism.