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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.
61

Télévision et transformation des imaginaires et des rôles de genre dans les sociétés arabes : programmation et réception des chaînes satellitaires au liban, en egypte, en tunisie, au qatar et aux emirats arabes unis / Television and transformation of imaginary and gender roles in arab society : programmig and reception of satellite channels in lebanon, egypt, tunisia, qatar and united arab emirats

Hussein, Hasna 04 November 2013 (has links)
Cette thèse montre, par l’étude de la nouvelle visibilité des femmes dans les programmes des chaînes satellitaires, comment la télévision contribue à l’hybridation socioculturelle, à l’acculturation et à l’incorporation sélective des valeurs et des normes de genre. Il s’agit dans un premier temps d’un travail de contextualisation de la complexité des représentations des femmes à la télévision depuis la diffusion satellitaire, à partir d’une étude comparative des scènes télévisuelles entre cinq pays arabes: le Liban, la Tunisie, l’Égypte, le Qatar et les Émirats-Arabes-Unis. Dans un second temps, l’analyse de 77 entretiens avec des présentatrices des 18 chaînes satellitaires dans les pays ciblés, se focalise sur les processus de féminisation et de professionnalisation du métier de présentatrice, qui sont des facteurs majeurs non seulement dans la construction de la diversité des images et des modèles féminins véhiculés par la télévision, mais aussi dans les transformations de la perception des femmes et de leurs rôles dans la société. À travers cette diversité ambivalente, voire même contradictoire, la télévision contribue à introduire de l’incohérence et de l’hybridité stimulant l’imagination des téléspectateurs, particulièrement sur le plan de leur conception des rôles des hommes et des femmes. C’est précisément sur cette dimension que s’étudie la troisième partie de la thèse. Celle-ci s’appuie sur les études des expériences de réceptions auprès de 66 participants et participantes à 16 séances de focus groups réalisées essentiellement au Liban. Ce corpus avec lequel nous interrogeons les rôles et les imaginaires de genre est un moyen privilégié pour saisir les enjeux de la globalisation télévisuelle et de la « modernité » dans les sociétés arabes contemporaines. / The new visibility of women on Satellite TV Channels is the product of transformations of the media landscape. The explosion of Arab Satellite Channels (ASC) since 1990 have allowed women in the Arab World to be present in a wide range of media professions, particularly TV anchor. Today, we can notice a diversity of women anchor’s figures after the emergence of many specialized and generalized satellite channels. Indeed, women are present in news, social and political talk shows, sport, religion, fashion, food, and reporting. Some of those figures outcome of political, social and economic logic of specific national context (Egypt, Tunisia and Saudi Arabia), while others are the result of professionalism competition of channels and subjective experience of women anchors-as new actors on ASC- in transnational context (Lebanon, Qatar and Dubai). A key factor in this new configuration of women’s visibility on Arab media landscape is the transgressing of the traditional male domain. Indeed, many women anchors proved impressive strides in debate TV programs and reporting. Based on their professional experience, high education and talents, they proved to be equal to men and sometimes more effective and influential. Women anchor’s new visibility in ASC affects women’s professional situation, shapes gender relationships, women’s participation in the public sphere, and family’s perceptions and retention of women into Arab Societies.
62

ANCHORING TO LIGHTWEIGHT CONCRETE: CONCRETE BREAKOUT STRENGTH OF CAST-IN, EXPANSION, AND SCREW ANCHORS IN TENSION

Ting-Wei Wang (7040873) 16 August 2019 (has links)
The use<b></b>of lightweight concrete in the concrete industry provides economical and practical advantages. Structural anchors are commonly used in the industry for various structural applications. In <i>ACI 318-19: Building Code Requirements for Structural Concrete and Commentary</i>, a modification factor, λ<i><sub>a</sub></i>, is specified for the calculated design strengths of anchors installed in lightweight concrete that experience concrete or bond failure. The modification factor consists of the general lightweight concrete modification factor,λ, specified in the code multiplied by an additional reduction factor dependent on the anchor and failure type. For the concrete breakout strength of expansion and screw anchors in lightweight concrete, the value of λ<i><sub>a</sub></i>is specified as 0.8λ. For the concrete breakout strength of cast-in anchors in lightweight concrete, the value of λ<i><sub>a</sub></i>is 1.0λ. In both cases, however, the specified value of λ<i><sub>a</sub></i>is based on limited test data. A research program was therefore conducted to provide the data needed for more appropriate lightweight modification factors. A primary objective of the research was to evaluate the concrete breakout strengths of cast-in, expansion, and screw anchors installed in lightweight concrete by conducting a systematic experimental program that included various types of lightweight concrete. More specifically, the experimental program included tension tests on torque-controlled expansion anchors, displacement-controlled expansion anchors, and screw anchors from four manufacturers in addition to tension tests on cast-in headed stud anchors. A total of seven concrete types were included in the research: one normalweight concrete mixture and six lightweight concrete mixtures. The lightweight concrete included sand-lightweight and all-lightweight mixtures composed ofexpanded shale, clay, and slate aggregates. The results of the experimental program are compared to limited data available from previous tension tests on anchors in lightweight concrete. Based on the results of the research, revised lightweight concrete modification factors for the concrete breakout design strengths of the anchor types included in the test program are provided.
63

A contribuição do sistema âncora em diferentes pontos de contato corporal sobre o controle da postura em idosos / The contribution of the anchor system on different body contact points in the postural control of older adults

Silva, Jair Araujo Lopes da 28 April 2016 (has links)
O aumento no número de idosos nos últimos anos trouxe impactos sociais e econômicos. O processo de envelhecimento e/ou patologias específicas trazem consigo perdas progressivas sensoriais, motoras e de processamento central que estão relacionadas com o aumento das quedas com o avanço da idade. Estas perdas predispõem o idoso a sofrer com limitações físicas de mobilidade, medo de cair ou mesmo sofrer com quedas. Este quadro evoca a necessidade de atenção especial à qualidade de vida dos idosos, com novas intervenções e programas de reabilitação física. Dentre essas novas abordagens para melhorar o funcionamento do controle postural, temos a adição de informação háptica que contribui para reduzir a oscilação corporal durante a manutenção da postura ereta. Uma das formas de adicionar informação háptica ao sistema de controle postural é pelo sistema âncora. Este é uma ferramenta não rígida que consiste de dois cabos maleáveis com 125g de massa repousando no solo e com a outra extremidade segura pelas mãos (âncora tradicional). Considerando que o toque leve em diferentes partes do corpo reduz a oscilação corporal, é possível, da mesma forma, que o uso do sistema âncora em diferentes partes do corpo seja efetivo. Portanto, o objetivo desse estudo foi avaliar o efeito do uso do sistema âncora em diferentes pontos de contato (antebraço e ombro) sobre a oscilação corporal de idosos durante a manutenção da postura ereta Trinta idosos participaram do presente estudo. Eles permaneceram na postura ereta com os pés na posição semi tandem sobre uma plataforma de força para a obtenção do deslocamento do centro de pressão (CP). Cinco condições experimentais foram realizadas: sem âncora, âncora tradicional, âncoras nas mãos fixadas com presilhas, âncoras nos antebraços fixadas com presilhas e âncoras nos ombros fixadas com presilhas. Baseada nos dados fornecidos pelo deslocamento do CP foram calculadas as variáveis: área da elipse, amplitude média de oscilação e velocidade média de oscilação. Os resultados mostraram uma redução da área da elipse e da amplitude média de oscilação na direção anteroposterior nas condições com as âncoras posicionadas nas mãos (tradicional e presilha) e antebraços em comparação a condição sem âncora. Os resultados apontaram ainda uma redução da velocidade média de oscilação na direção anteroposterior na condição de âncoras nos antebraços em comparação a condição sem âncora. Na direção mediolateral, a velocidade média de oscilação reduziu nas condições de âncora fixada nas mãos e antebraços em comparação a condição sem âncora. O uso do sistema âncora na região dos ombros não trouxe redução da oscilação corporal. Em conclusão, o sistema âncora reduziu a oscilação corporal quando o sistema âncora foi posicionado nos antebraços da mesma forma que quando foi fixado/seguro nas mãos. A melhora observada com o uso das âncoras parece não estar relacionada com a quantidade de receptores táteis no ponto de contato dos cabos das âncoras / The increase in the number of older adults in recent years has brought social and economic impacts. The process of aging and/or specific diseases carries progressive sensory, motor and central processing losses that are related to the increased rate of falls with increasing age. These losses predispose the elderly to suffer from physical mobility limitations, fear of falling or even falls. This scenario evokes the need for special attention to the quality of life for older adults, with new interventions and physical rehabilitation programs. Among these new approaches to improve the functioning of the postural control system, we have the addition of haptic information which helps to reduce body sway during maintenance of upright posture. One way to add haptic information to the postural control system is the anchor system. It consists of a non-rigid tool with two flexible cables with 125g mass resting on the ground and with the other end secured by the hands (traditional anchor). Since light touch in different body regions reduces body sway, it is possible, likewise, that the use of the anchor system in different parts of the body to be effective in reducing body sway. Therefore, the aim of this study was to evaluate the effect of using the anchor system in different points of contact (forearm and shoulder) on body sway of older adults during maintenance of upright posture Thirty older adults participated in this study. They stood upright on a force plate to obtain center of pressure displacement (CoP) with their feet in the semi tandem position. Five experimental conditions were carried out: no anchor, traditional anchor, anchors on the hands secured with clasps, anchors on the forearms secured with clasps and anchors on shoulders secured with clasps. Based on data provided by the CP displacement, the following variables were calculated: ellipse area, mean sway amplitude and mean sway velocity. The results showed a reduction in the area of the ellipse and in the mean sway amplitude (anteriorposterior direction) for conditions with anchors hold on the hands and forearms compared to the no anchor condition. The results also indicated a reduction in the mean sway velocity (anterior-posterior direction) with the anchors on the forearms compared to the no anchor condition. For the medial-lateral direction, the mean sway velocity reduced with the anchor on the hands and forearms compared to the no anchor condition. The use of the anchor system in the shoulder region did not reduce body sway. In conclusion, the use of the anchor system reduced body sway when it was placed on the forearms in the same way as when placed/secured on the hands. The improvement observed with the use of anchors does not seem to be related to the amount of tactile receptors in the point of contact of the anchor cables
64

Aplicação da técnica da fotoelasticidade na análise de fundações por estacas helicoidais / Aplication of the photoelastic method to the analysis of helical screw pile foundations

Schiavon, José Antonio 23 July 2010 (has links)
A técnica da fotoelasticidade pode ser particularmente útil na análise de tensões em sistemas com geometrias complexas. Em um equipamento chamado polariscópio, um feixe de luz polarizada atravessa o modelo fotoelástico que representa o protótipo. Ao submeter este modelo a um carregamento, faixas de diferentes cores poderão ser visualizadas. Cada cor é associada a um nível de tensão. As tensões observadas no modelo fotoelástico podem ser comparadas com as tensões determinadas nos modelos numéricos ou analíticos. Em casos específicos, o problema da distribuição de tensões em uma fundação pode ser analisado com emprego da fotoelasticidade. A análise do comportamento de estacas helicoidais através da técnica da fotoelasticidade pode ser então de grande valia para estudos mais aprofundados deste sistema. O principal objetivo desta pesquisa foi viabilizar este método experimental para ser aplicado no Departamento de Geotecnia da EESC em análises de tensões em sistemas geotécnicos. Para validar as análises experimentais, tensões observadas em modelos de geometria simples foram comparadas com as tensões determinadas por meio de modelagem numérica com o método dos elementos finitos. O comportamento da fundação por estaca helicoidal observado pela técnica da fotoelasticidade mostrou semelhança ao observado na modelagem numérica. Por meio da distribuição de tensões, foi possível avaliar a influência da geometria helicoidal da lâmina e da profundidade de instalação da ancoragem no terreno. / The photoelastic method can be particularly useful for stress analysis with complex geometry systems. In equipment called polariscope, a polarized light beam crosses the photoelastic model that represents the prototype. Submitting this model to a load, fringes of different colors can be visualized. Each color is associated to a stress level. The stresses corresponding to the observed fringes on the photoelastic model can be compared to the stresses obtained through analytical or numerical models. In specific cases, the stress distribution problem can be analyzed with the use of photoelasticity. The photoelastic analysis of the helical pile behavior can then be valuable for further studies of this system. The main objective of this research was enabling this experimental method to be applied in the Department of Geotechnical Engineering of EESC in geotechnical systems stress analysis. To validate the experimental analysis, stresses observed in simple geometry models have been compared to those stresses determined by numerical modeling with the finite element method. The observed behavior of the helical pile foundation by photoelastic method showed similarity to that one observed through numerical modeling. Stress distribution analyses allowed evaluating the influence of helical blade geometry and the depth of installation.
65

Desenvolvimento de ferramentas computacionais para a simulação do fenômeno de cravação de estacas torpedos pelo método de partículas Moving Particle Semi-implicit  (MPS). / Computacional tools development for simulation of the torpedo anchor impact based on the Moving Particle Semi-implicit (MPS) method.

Ribeiro, Gabriel Henrique de Souza 03 December 2018 (has links)
Este trabalho tem como objetivo desenvolver ferramenta computacional para simulação e análise do fenômeno de penetração e cravação de estacas torpedos em solo marítimo. A abordagem será baseada no método Moving Particle Semi-Implicit (MPS). Por se tratar de um método de partícula, sem malha, o mesmo apresenta grande flexibilidade na modelagem de problemas de interação fluido-sólido com fragmentação ou junção de superfície livre e grandes deslocamentos ou deformações dos sólidos, fenômenos esses presentes no impacto e cravação da estaca no solo marítimo. Para isso, dois desafios foram elencados: a modelagem dos solos como fluidos não-newtonianos e a determinação da força de arrasto viscosa na superfície de sólidos. A modelagem do fluido não-newtoniano foi feita considerando os modelos de Power Law, Bingham e Herschel-Bulkley. O cálculo da força de arrasto viscosa foi avaliado determinando-se o gradiente da velocidade do fluido na direção normal à parede com base na regressão polinomial. Por simplicidade, foi considerada a hipótese de que a variação da velocidade na direção tangencial da parede é muito menor se comparada a variação da mesma na direção do vetor normal. O método implementado, assim como o escoamento de fluidos não-newtonianos, foi validado por meio de comparação entre o resultado obtido de simulações com geometrias pré-definidas e as respostas analíticas para tais casos. Como exemplo de aplicação da ferramenta computacional desenvolvida, um caso simplificado de cravação das estacas torpedos foi simulado avaliando-se o seu deslocamento dentro do solo e os esforços cisalhantes a ela submetidas. / This work aims to develop computational tools to simulate and analysis the torpedo anchor penetration in marine soil. The approach will be based on the Moving Particle Semi-Implicit (MPS) method. Because it is a meshless method, it is extremely flexible to model fluid-solid interaction with fragmentation or junction of free surface and large displacements or deformations of solids, phenomena presented at the torpedo anchor impact. Two challenges were listed: the modeling of soils as non-Newtonian fluids and the determination of the viscous drag on the solids surface. The modeling of non-Newtonian fluid was done based on the Power Law, Bingham and Herschel-Bulkley models. The calculation of the viscous drag was evaluated by determining the velocity gradient in the normal direction of the wall based on polynomial regression considering the fluid particles near the solid wall. In this work, for sake of simplicity, the hypothesis that the velocity variation in the tangential direction of the wall is much smaller compared to its variation in the normal direction is adopted. The proposed technique, as well as the flow of non-Newtonian fluids, were validated comparing the results obtained in flow simulations with predefined geometries with the expected analytical responses. As an example of the application of the computational tools developed, a simplified case of torpedo penetration was simulated by evaluating its displacement and the shear stresses submitted to it.
66

Desenvolvimento de ferramentas computacionais para a simulação do fenômeno de cravação de estacas torpedos pelo método de partículas Moving Particle Semi-implicit  (MPS). / Computacional tools development for simulation of the torpedo anchor impact based on the Moving Particle Semi-implicit (MPS) method.

Gabriel Henrique de Souza Ribeiro 03 December 2018 (has links)
Este trabalho tem como objetivo desenvolver ferramenta computacional para simulação e análise do fenômeno de penetração e cravação de estacas torpedos em solo marítimo. A abordagem será baseada no método Moving Particle Semi-Implicit (MPS). Por se tratar de um método de partícula, sem malha, o mesmo apresenta grande flexibilidade na modelagem de problemas de interação fluido-sólido com fragmentação ou junção de superfície livre e grandes deslocamentos ou deformações dos sólidos, fenômenos esses presentes no impacto e cravação da estaca no solo marítimo. Para isso, dois desafios foram elencados: a modelagem dos solos como fluidos não-newtonianos e a determinação da força de arrasto viscosa na superfície de sólidos. A modelagem do fluido não-newtoniano foi feita considerando os modelos de Power Law, Bingham e Herschel-Bulkley. O cálculo da força de arrasto viscosa foi avaliado determinando-se o gradiente da velocidade do fluido na direção normal à parede com base na regressão polinomial. Por simplicidade, foi considerada a hipótese de que a variação da velocidade na direção tangencial da parede é muito menor se comparada a variação da mesma na direção do vetor normal. O método implementado, assim como o escoamento de fluidos não-newtonianos, foi validado por meio de comparação entre o resultado obtido de simulações com geometrias pré-definidas e as respostas analíticas para tais casos. Como exemplo de aplicação da ferramenta computacional desenvolvida, um caso simplificado de cravação das estacas torpedos foi simulado avaliando-se o seu deslocamento dentro do solo e os esforços cisalhantes a ela submetidas. / This work aims to develop computational tools to simulate and analysis the torpedo anchor penetration in marine soil. The approach will be based on the Moving Particle Semi-Implicit (MPS) method. Because it is a meshless method, it is extremely flexible to model fluid-solid interaction with fragmentation or junction of free surface and large displacements or deformations of solids, phenomena presented at the torpedo anchor impact. Two challenges were listed: the modeling of soils as non-Newtonian fluids and the determination of the viscous drag on the solids surface. The modeling of non-Newtonian fluid was done based on the Power Law, Bingham and Herschel-Bulkley models. The calculation of the viscous drag was evaluated by determining the velocity gradient in the normal direction of the wall based on polynomial regression considering the fluid particles near the solid wall. In this work, for sake of simplicity, the hypothesis that the velocity variation in the tangential direction of the wall is much smaller compared to its variation in the normal direction is adopted. The proposed technique, as well as the flow of non-Newtonian fluids, were validated comparing the results obtained in flow simulations with predefined geometries with the expected analytical responses. As an example of the application of the computational tools developed, a simplified case of torpedo penetration was simulated by evaluating its displacement and the shear stresses submitted to it.
67

Desenvolvimento de elementos de fixação (âncoras de suturas) em materiais biocompatíveis através de processo de Manufatura Aditiva / Development of elements of fixation (suture anchor) in biocompatible materials through the process of additive manufacture

Del Monte, Fernando Ferreira 01 December 2016 (has links)
Atualmente a área de saúde vem buscando auxílio na engenharia para a contribuição no estudo e confecção de próteses para casos específicos de fraturas ou doenças ósseas. Com o avanço da tecnologia surgiram processos de manufatura que tornam possível a fabricação de próteses personalizadas. Uma dessas tecnologias é a manufatura aditiva. O grande desafio no momento está na fabricação de próteses por manufatura aditiva que combinem desempenho biomecânico e resistência estrutural. Nesse contexto, o objetivo deste trabalho é desenvolver elementos de fixação, especificamente âncoras de sutura de polímeros PEEK e PEKK, considerando seus requisitos estruturais através de simulações pelo método dos elementos finitos, e considerando que sejam fabricadas através de processos de manufatura aditiva. Este desenvolvimento permitirá a substituição de âncoras de sutura de liga de titânio, hoje largamente empregadas pelos cirurgiões, por âncoras de sutura de polímeros biocompatíveis, o que possibilitará que estes polímeros sejam absorvidos pelo corpo humano em curto e médio prazo, permitindo a completa restituição do osso afetado, melhorando a qualidade de vida do paciente pós-cirurgia. Os resultados obtidos neste trabalho indicam que a técnica poderá resultar em próteses com a biocompatibilidade desejada e resistência mecânica adequada. Próteses permanentes (articulações) ou provisórias (âncoras de sutura) seriam um dos critérios para a escolha do material a ser utilizado, absorvível ou não pelo corpo humano. / Nowadays medicine is searching assistance from engineering that may contribute in studies and confection of prothesis to specific cases of fractures and bone diseases. With the advance of technology new processes of manufacture were risen, making possible the confection of personalized prothesis. The biggest challenge of the moment is in the manufacture of additive prothesis that can combine biomechanics performance and structural resistance. In this context, the objective of this dissertation is to develop PEEK and PEKK polymer suture anchors, considering its structural requirements, taking into account their mechanical strength, through simulation by the finite element method, and considering additive manufacturing processes. This development will allow the replacement of titanium alloy suture anchors, now widely used by surgeons by suture anchors of biocompatible polymers, which enable these polymers to be absorbed by the human body in the short and medium term, allowing full regeneration of affected bone, improving the quality of life of the patient. The results of this study indicate that the technique could result in prosthesis with the desired biocompatibility and adequate mechanical strength. Permanent prosthesis (joints) or temporary (suture anchors) would be one of the criteria for the choice of material to be used, absorbable or non absorbable by the human body.
68

Controle da postura em idosos com adição de informação háptica: relação com a visão e a somatossensação / Postural control in older adults with the addition of haptic information: relationship with vision and somatosensation

Gonzales, Leandro Cesar 14 April 2016 (has links)
Embora o uso do sistema âncora reduza a oscilação corporal em idosos, ainda não está claro como a informação háptica adicional interage com os outros sistemas sensoriais. Assim, o objetivo deste estudo foi avaliar a contribuição do sistema âncora na oscilação corporal de idosos durante a postura ereta semi estática com diferentes manipulações sensoriais: visão (com e sem) e somatossensação (superfície rígida e de espuma). Trinta idosos participaram desse estudo. Eles foram instruídos a ficar em pé sobre uma plataforma de força, com os pés afastados na largura do ombro. Três fatores foram manipulados: uso do sistema âncora, disponibilidade de visão e textura da superfície de suporte. O sistema âncora é constituído de dois cabos flexíveis seguros pelas mãos com cargas de 125 g conectados a cada extremidade que fica em contato com o solo. Nas tentativas sem visão, os participantes fecharam os olhos e uma venda foi colocada sobre os olhos. Na situação de olhos abertos os participantes fixaram o olhar em um alvo posicionado na altura dos olhos. Para a manipulação da textura da superfície, uma espuma com as dimensões da plataforma de força foi colocada sobre a mesma. Na condição de superfície rígida, os participantes permaneceram em contato diretamente com a superfície da plataforma de força. Com base no deslocamento do centro de pressão (CP), foram calculadas as seguintes variáveis: área da elipse contendo 95% dos dados do deslocamento do CP, amplitude média de oscilação (AMO) e velocidade média de oscilação (VMO) para quantificar a oscilação corporal. Os resultados da análise estatística para a área da elipse e para a VMO revelaram efeito principal de âncora (p<=0,0001), visão (p<=0,0001) e superfície (p<=0,0001), assim como interação entre visão e superfície (p<=0,0001) e âncora e superfície (p=0,002). Para a AMO os resultados revelaram efeito principal de âncora (p<=0,0001), visão (p<=0,0001) e superfície (p<=0,0001) e interação entre visão e superfície (p<=0,0001). O uso da âncora reduziu a oscilação corporal nas três variáveis analisadas. Por outro lado, a ausência de visão e a superfície de espuma aumentaram a oscilação corporal. O uso da âncora não contribuiu para reduzir a oscilação corporal na superfície rígida. Porém, na superfície de espuma o uso da âncora reduziu a oscilação corporal. O sistema âncora contribuiu para reduzir a oscilação corporal e essa redução foi mais efetiva quando o participante estava sobre a superfície de espuma. Portanto, conclui-se que em situações mais desafiadoras o uso do sistema âncora parece ser mais efetivo / Although the use of the anchor system reduces body sway in older adults, it is not clear how the additional haptic information interacts with other sensory systems. The purpose of this study was to evaluate the anchor system contribution to postural sway in older adults during a quiet standing task with different sensory manipulations: vision (with and without) and somatosensation (with and without a foam on the support surface). Thirty individuals participated in this study. They stood on a force plate, with their feet apart at shoulder width. Three factors were manipulated: use of the anchor system, vision availability and support surface texture. The anchor system consists of two flexible cables hold by the hands with loads of 125 g connected to each end that is in contact with the ground. In the trials without vision, participants closed their eyes and a blindfold was placed over their eyes. In the eyes open condition, participants fixed their gaze on a target positioned at eye level. For the manipulation of texture of the surface, a foam with the dimensions of the force plate was placed over it. In the rigid surface condition, participants stood directly over the surface of the force plate. Based on center of pressure (CP) displacement, the following variables were calculated: 95% ellipse area, mean sway amplitude (MSA), and mean sway velocity (MSV). The statistical analysis results for the ellipse area and MSV showed main effect of anchor (p<=0.0001), vision (p<=0.0001) and surface (p<=0.0001), as well as interaction between vision and surface (p<=0.0001) and anchor and surface (p=0.002). For MSA, the results revealed main effect of anchor (p<=0.0001), vision (p<=0.0001) and surface (p<=0.0001) and interaction between vision and surface (p<=0.0001). The use of the anchor reduced body sway in all three variables analyzed. Moreover, the absence of vision and the foam surface increased body sway. The use of the anchor did not contribute to reduce body sway on the rigid surface, but on the foam surface the use of anchor reduced body sway. The anchor system helped reducing body sway and this reduction was more effective when the participant was on the foam surface. Therefore, it follows that in more challenging situations the use of the anchor system appears to be more effective.
69

Do the Presence of Anchor Institutions Increase Opportunities in Life? : Exploring the Effects of Higher Education Institutions on Pupils’ School Achievements in different neighbourhood types

Hachem, Maéva January 2019 (has links)
The number of universities in Sweden has increased since the 1960s and universities have been discussed to have economic and social advantages to the community they are established in. At the same time, residential segregation is an increasing problem which affects the opportunities in life of the most vulnerable. This study aims to explore if the presence of one or several anchor institutions may have an effect on the school achievements of pupils from neighbourhoods with different socioeconomic status in secondary school and upper secondary school. Furthermore, it aims to investigate how the presence of HEIs affect adolescents’ opportunities in life, especially in vulnerable neighbourhoods. The effects of HEIs on the neighbourhoods with different socioeconomic status in Sweden are measured through linear regression analyses with interaction effects. The findings suggest that (1) the presence of university campuses have an equalisation effect on the school achievements of secondary and upper secondary school pupils; (2) the university design matters: new universities have an equalisation effect on the school achievements in contrary to old universities; (3) the presence of a university hospital does not have an improving effect on the grades like universities do, in contrary, the findings suggest that they have a negative effect; and finally (4), there are some evidence indicating that the findings can be explained by endogenous neighbourhood effects, as the presence of universities increase the number of role models within the community, which would affect the school achievements of secondary and upper secondary school pupils.
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Characterising and Mapping Porcine Endogenous Retroviruses (PERVs)

Lee, Jun Heon January 2001 (has links)
The initial focus of this PhD project was on comparative gene mapping. Comparative gene mapping is facilitated by consensus PCR primers which amplify homologous gene fragments in many species. As a part of an international co-ordinated programme of comparative mapping in pigs, 47 CATS (Comparative Anchor Tagged Sequence) consensus primer pairs for loci located on human chromosomes 9, 10, 20, and 22, were used for amplifying homologous loci in pigs. After optimization of PCR conditions, 23 CATS products have confirmed by comparison with homologous sequences in GenBank. A French somatic cell hybrid panel was used to physically map the 6 porcine CATS products distinguishable from rodent background product, namely ADRA1A, ADRA2A, ARSA, GNAS1, OXT and TOP1. Of these, the map location of ADRA1A and OXT showed inconsistency with the previously recognised conserved relationship between human and pig. The other four loci mapped to positions consistent with known syntenic relationships. Despite low levels of polymorphism, frequently indistinguishable rodent and porcine products in somatic hybrids and some confusion of identity of gene family members, these CATS primers have made a useful contribution to the porcine-human comparative map. The focus of the project then changed to genetic and molecular characterisation of endogenous retroviruses in pigs and their relatives. Pigs are regarded as a potentially good source of organs and tissues for transplantation into humans. However, porcine endogenous retroviruses have emerged as a possible problem as they can infect cultured human cells. Two main types of pig retrovirus, determined by envelope protein, PERV-A and PERV-B, are widely distributed in different pig breeds and a third less common type, PERV-C, has also been recognised. Endogenous retroviruses were analyzed from the Westran (Westmead transplantation) inbred line of pig, specially bred for biomedical research. Thirty-one 1.8 kb env PCR product clones were sequenced after preliminary screening with the restriction enzymes KpnI and MboI. Five recombinant clones between A and B were identified. 55% of clones (17/31) sequenced had stop codons within the envelope protein-encoding region, which would prevent the retrovirus from making full-length envelope protein recognizable by cell-surface receptors of the virus. The endogenous viruses were physically mapped in Westran pigs by FISH (Fluorescence In Situ Hybridisation) using PERV-A and PERV-B envelope clones as probes. Preliminary FISH data suggest that there are at least 22 PERVs (13 PERV-A and 9 PERV-B) and the chromosomal locations of these in the Westran strain are quite different from European Large White pigs. The sequences and mapping results of inbred Westran pig suggest that there are relatively few PERV integration sites compared with commercial pigs and further that a large proportion of clones are defective due to premature stop codons in the envelope gene. To investigate the relationship of endogenous retroviruses in peccaries and pigs, a set of degenerate primers was used to amplify peccary retroviral sequences. The sequences of two putative retroviral clones showed close homology, albeit with a 534 bp deletion, to mouse and pig retroviral sequences. Also, four non-target sequences were amplified from peccary with the degenerate retroviral primers. They are a part of the peccary cofilin gene, a SINE, and a sequence containing a microsatellite. The peccary endogenous retroviral sequences are significant in that they are the first such sequences reported in peccary species and repudiate old claims in the literature that peccaries do not have C-type retroviral sequences.

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