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Espaços negros na cidade pós-abolição: São Carlos, estudo de caso / Black spaces on the post abolition city: São Carlos, case studyNatalia Alexandre Costa 15 May 2015 (has links)
Trata do processo de configuração dos núcleos de fixação urbana de ex-escravos, tendo como estudo de caso a cidade de São Carlos, do interior paulista, a partir de três bairros surgidos contemporaneamente à Abolição, com grande presença negra: Vila Isabel, Vila Nery e Vila Pureza. A historiografia sobre os escravos no período pós-abolição do Brasil vem se tornando cada vez menos rara, no entanto ainda é nebulosa a influência exercida pela herança cultural dos ex-escravos no ambiente da cidade por eles ocupado, considerando aspectos materiais e imateriais. O presente trabalho trata da relação entre os bairros e o espaço em que eles se inseriram, bem como as relações espaciais entre as habitações e outros equipamentos dentro dos próprios núcleos. Analisa, ainda, as moradias, notando a ocupação do lote, a distribuição interna dos ambientes, o uso e representação de cada espaço e as transformações ocorridas ao longo do tempo. Por fim, visa contribuir para ampliar a historiografia do negro em nosso país, a partir de uma perspectiva que o considera ativo e atuante no processo de construção das cidades após abolição. / This configuration process of urban fixing neighborhoods of former slaves, taking as a case study the city of São Carlos, in São Paulo State, from three districts emerged contemporaneously with the abolition of slavery, with large black presence: Vila Isabel, Vila Nery and Vila Pureza. The historiography of the slaves in the post-abolition period in Brazil is becoming less and less rare, however it is still cloudy the influence of the cultural heritage of the former slaves in the city environment they occupy, considering material and immaterial aspects. This paper deals with the relationship between the neighborhoods and the space in which they were inserted, and the spatial relationships between housing and other equipment inside the neighborhoods themselves. It also analyzes the Vilas, noting the lot occupation, the internal distribution of environments, the use and representation of each space and the changes occurring over time. Finally, it aims to contribute to enlarge the historiography of black people in our country, from a perspective that considers them active in the construction process of the cities after abolition (1888).
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Espaços negros na cidade pós-abolição: São Carlos, estudo de caso / Black spaces on the post abolition city: São Carlos, case studyCosta, Natalia Alexandre 15 May 2015 (has links)
Trata do processo de configuração dos núcleos de fixação urbana de ex-escravos, tendo como estudo de caso a cidade de São Carlos, do interior paulista, a partir de três bairros surgidos contemporaneamente à Abolição, com grande presença negra: Vila Isabel, Vila Nery e Vila Pureza. A historiografia sobre os escravos no período pós-abolição do Brasil vem se tornando cada vez menos rara, no entanto ainda é nebulosa a influência exercida pela herança cultural dos ex-escravos no ambiente da cidade por eles ocupado, considerando aspectos materiais e imateriais. O presente trabalho trata da relação entre os bairros e o espaço em que eles se inseriram, bem como as relações espaciais entre as habitações e outros equipamentos dentro dos próprios núcleos. Analisa, ainda, as moradias, notando a ocupação do lote, a distribuição interna dos ambientes, o uso e representação de cada espaço e as transformações ocorridas ao longo do tempo. Por fim, visa contribuir para ampliar a historiografia do negro em nosso país, a partir de uma perspectiva que o considera ativo e atuante no processo de construção das cidades após abolição. / This configuration process of urban fixing neighborhoods of former slaves, taking as a case study the city of São Carlos, in São Paulo State, from three districts emerged contemporaneously with the abolition of slavery, with large black presence: Vila Isabel, Vila Nery and Vila Pureza. The historiography of the slaves in the post-abolition period in Brazil is becoming less and less rare, however it is still cloudy the influence of the cultural heritage of the former slaves in the city environment they occupy, considering material and immaterial aspects. This paper deals with the relationship between the neighborhoods and the space in which they were inserted, and the spatial relationships between housing and other equipment inside the neighborhoods themselves. It also analyzes the Vilas, noting the lot occupation, the internal distribution of environments, the use and representation of each space and the changes occurring over time. Finally, it aims to contribute to enlarge the historiography of black people in our country, from a perspective that considers them active in the construction process of the cities after abolition (1888).
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Étude numérique et expérimentale du mécanisme de lubrification eX-Poro-HydroDynamique (XPHD) / Numerical and experimental study of eX-Poro-HydroDynamic lubrication mechanismKunik, Serguei 03 May 2018 (has links)
La lubrification eX-Poro-HydroDynamique (XPHD) est un mécanisme de lubrification d’inspiration biomimétique. Il s’agit principalement d’un écoulement dans un milieu poreux, dont la phase solide représentée par des fibres, induit des forces élastiques de compression considérées comme négligeables par rapport aux forces hydrodynamiques générées à l’intérieur du milieu poreux. L’idée essentielle de la lubrification XPHD consiste en remplacement du matériau antifriction et du film de fluide mince, traditionnellement utilisé dans les solutions classiques, par une couche poreuse imbibée d’un fluide qui fournit plus grande capacité de charge. Ce type de lubrification représente une solution technologique totalement nouvelle (en rupture avec la solution classique) qui peut permettre de remplacer les lubrifiants pétroliers, de créer des systèmes tribologiques autolubrifiants et donc plus écologiques et moins coûteux. Ce travail de recherche est donc focalisé sur l’évolution des performances de la lubrification XPHD dans le cadre d’un mouvement tangentiel, adapté à l’étude de butées pour faible et moyenne vitesses de rotation. Dans ce contexte scientifique, une étude approfondie d’un matériau poreux présélectionné (mousse en polyuréthane) fut réalisée avec le but de déterminer les caractéristiques physiques et les paramètres cruciaux pour la lubrification XPHD: la porosité et la perméabilité du matériau poreux. Les modèles théorique et numérique de lubrification XPHD proposés se basent sur l’équation de Darcy-Brinkman et les hypothèses de la lubrification classique, ainsi que l’écoulement à l’intérieur du milieu poreux sont prédit avec une nouvelle forme de l’équation de Reynolds. Le banc d’essais spécialement développé permet d’étudier expérimentalement le mécanisme de lubrification XPHD pour des différents types de dislocateur en combinaison avec des liquides newtoniens et nonnewtoniens. Une description détaillée du banc d’essais et de tous les dispositifs expérimentaux utilisés ainsi que la comparaison des résultats de modélisation et des résultats expérimentaux sont présentés. / The eX-Poro-HydroDynamic (XPHD) lubrication is a new biomimetic inspired lubrication mechanism. It consists of self-sustained fluid films generated within highly compressible porous layers imbibed with liquids, whose solid phase represented by fibers, induces compressive elastic forces considered negligible compared to the hydrodynamic forces generated inside the porous medium. The essential idea of XPHD lubrication is to replace the antifriction material and the thin fluid film, traditionally used for classical sliding motion, with a porous layer imbibed with a fluid that provides a greater load capacity. This type of lubrication represents a completely new technological solution (in rupture with the classical one) that can replace petroleum lubricants, create self-lubricating and therefore more ecological and less expensive tribological systems. This research work is focused on the evolution of XPHD lubrication performances in the context of a tangential movement, adapted to the study of thrust bearing for low and medium rotation speeds. In this scientific context, a thorough study of a preselected porous material (polyurethane foam) was carried out with the aim of determining the physical characteristics and the crucial parameters for XPHD lubrication: the porosity and the permeability of the porous material. The theoretical and numerical models of the XPHD lubrication proposed are based on the Darcy-Brinkman equation and the classical lubrication hypothesis, as well as the flow within the porous media is predicted with a new form of the Reynolds equation. The specially developed test rig is used to investigate experimentally the mechanism of the XPHD lubrication for different types of thrust bearing in combination with Newtonian and non-Newtonian liquids. A detailed description of the test rig and all used experimental devices, as well the comparison between the experimental and numerical results are presented.
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Avaliação das afecções odontológicas em pequenos felídeos neotropicais mantidos em cativeiro / Evaluation of dental diseases in small neotropical felids kept in captivityPrazeres, Rodrigo Filippi 08 May 2014 (has links)
Foram estudados 50 pequenos felídeos neotropicais adultos (25 machos e 25 fêmeas) de quatro espécies distintas - 15 jaguatiricas (Leopardus pardalis), 15 gatos-do-mato-pequenos (Leopardus tigrinus), 10 gatos-maracajás (Leopardus wiedii) e 10 gatos-mouriscos (Puma yagouaroundi), provenientes de quatro coleções zoológicas do Estado de São Paulo. A finalidade foi identificar alterações odontológicas macroscópicas, divididas em quatro grupos: 1. variações, anomalias e ausências dentárias; 2. doença periodontal; 3. traumatismos; 4. lesões de reabsorção dentária. Verificou-se que tais alterações são frequentes, mesmo em animais assintomáticos, sendo a halitose a manifestação clínica aparentemente mais comum. Dentre as alterações verificadas, a doença periodontal (88,0%) foi a mais prevalente, sendo cálculo dental e gengivite os principais achados clínicos, acometendo principalmente a face vestibular dos dentes maxilares. O segundo grupo de alterações odontológicas de maior prevalência foi o de traumatismos (66,0%), principalmente em Leopardus pardalis e Puma yagouaroundi, com destaque para a abrasão dentária, e maior acometimento dos dentes caninos. Ausência de dentes foi o achado mais prevalente no grupo das variações, anomalias e ausências dentárias (54,0%), predominando ausência de incisivo superior medial direito, segundo pré-molar superior direito, canino superior esquerdo e incisivos inferiores laterais, esquerdo e direito, com maior frequência em Puma yagouaroundi. Lesões de reabsorção dentária foram pouco prevalentes (10,0%), sendo observadas principalmente em dentes pré-molares e molares mandibulares. / There were studied 50 adult small neotropical felids (25 males and 25 females) from four species - 15 Leopardus pardalis, 15 Leopardus tigrinus, 10 Leopardus wiedii and 10 Puma yagouaroundi from four zoological collections of the State of São Paulo, Brazil. The objective was to identify macroscopic dental changes, divided into four groups: 1. variations, anomalies and missing teeth; 2. periodontal disease; 3. trauma; 4. resorptive lesions. It was found that such changes are frequent, even in asymptomatic animals, and halitosis is apparently the most common clinical manifestation. Among the changes, periodontal disease (88.0%) was the most prevalent, with dental calculus and gingivitis as major clinical findings, affecting mainly the vestibular surface of the maxillary teeth. The second group of higher prevalence dental findings was trauma (66.0%), mainly observed in Leopardus pardalis and Puma yagouaroundi mainly tooth abrasion, with prevalence of canine teeth. Dental absence was the most prevalent finding in the group of variations, anomalies and missing teeth (54.0%), predominating absence of right medial incisor, second right premolar, upper left incisors and lower right and left canine teeth, with major frequency in Puma yagouaroundi. Resorptive lesions were less prevalent (10.0%), being mainly observed in premolars and mandibular molars.
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Convergência de vias de desenvolvimento: análise da capacidade de formar órgãos in vitro em mutantes de tomateiro afetando a arquitetura foliar / Convergence of developmental pathways: in vitro analysis of organ formation capacity in tomato mutants affecting leaf architectureOliveira, Guilherme Pereira de 03 July 2015 (has links)
O cultivo in vitro de células, tecidos e órgãos vegetais, iniciado no começo do século XX, propiciou avanços no conhecimento científico e biotecnológico. O processo de regeneração in vitro depende tanto das condições de cultivo quanto da base genética dos explantes utilizados. Alguns autores postulam que a regeneração pode ser dividida em etapas e o balanço entre hormônios vegetais é responsável por determinar o destino dos explantes (e.g. formação de raízes, gemas ou calos). Em estudo realizado anteriormente, foi constatada a alta capacidade de regeneração de gemas caulinares adventícias in vitro do mutante Mouse-ears, que apresenta folhas com maior complexidade. Diante disso, neste trabalho outros mutantes que afetam a arquitetura foliar, como entire, procera, clausa, potato-leaf e Mouse-ears, foram avaliados ex vitro e in vitro, no \"background\" da cultivar Micro-Tom (MT). A caracterização fenotípica dos genótipos demonstrou que as mutações estudadas afetam vários outros aspectos do desenvolvimento, além das folhas. Muitas das diferenças observadas ex vitro, são em parte devidas à transição de estágio vegetativo para reprodutivo. Ao analisarmos os resultados de regeneração in vitro (formação de gemas caulinares e raízes adventícias; e crescimento de calos), nota-se que a capacidade organogenética de cada mutante não tem correlação com o grau de complexidade foliar, mas sim com tipo de mutação envolvida. Análises morfológicas de eventos in vitro e ex vitro quanto à formação de gemas caulinares adventícias e do meristema apical caulinar, respectivamente, denotam que ocorrem tanto similaridades quanto disparidades entre os dois processos. Os resultados indicam que provavelmente os mutantes entire (respota constitutiva a auxina por perda de função de um AUX/IAA) e Mouse-ears (super expressão do gene KNOX TKN2) atuam na etapa de indução de raízes e gemas, respectivamente, no processo de regeneração in vitro. Em contra partida, procera (resposta constitutiva a giberelina) atuaria na etapa de aquisição de competência ou retardo do desenvolvimento pós-indução. Além disso, TKN2 demonstrou ter um importante papel na formação de gemas caulinares adventícias in vitro. As vias para a formação de orgãos ex vitro (e.g. folhas, raízes, gemas axilares etc.) são diferentes da in vitro. Apesar disso, vários genes e moléculas recrutados em uma via de desenvolvimento ex vitro podem interferir na organogênese in vitro. / The in vitro culture of plant cells, tissues and organs, started at the beginning of the 20th century, has been leading to scientific and biotechnological advances ever since. The process of in vitro regeneration depends on the growth conditions as well as the genotype of the explant. Several authors postulated that regeneration can bedivided into steps and that the hormonal balance will determinate the fate of the explant (e.g. formation of roots, shoots or callus). In a previous study, it was found that the mutant Mouse-ears, which exhibits a more complex leaf architecture, has high capacity of shoot regeneration. Hence, in the present work others mutants affecting leaf architecture such as entire, procera, clausa, potato-leaf and Mouse-ears were measured ex vitro and in vitro in the MT background. These assessments aimed to investigate if there are similarities in organogenesis between in vitro and ex vitro. The phenotypic characterization of the genotypes showed that these mutations affect several aspects of plant development and not only the leaf architecture. Many differences observed ex vitro are in part due to the transition from vegetative to reproductive phase. When analyzing the results of in vitro regeneration (formation of adventitious shoots and roots; and callus growing) it is noticed that the organogenetic capacity of each mutant have no correlation with the degree of leaf complexity but with the type of mutation involved. Morphological analysis of in vitro and ex vitro events, such as formation of adventitious shoots and shaping of shoot apical meristem, respectively, denotes similarities and divergences between the processes. The results indicate that probably the mutants entire (constitutive response to auxin due to a loss-of-function in an AUX/IAA) and Mouse-ears (overexpression of a KNOX TKN2) act at the induction step of root and shoot, respectively, in the in vitro regeneration process. On the other hand, procera (constitutive response to gibberellin) acts at the competence step or the arrest of the development after induction. Furthermore, TKN2 showed an important role in the formation of in vitro adventitious shoots. The pathways for ex vitro organ formation (e.g. leaf, root, axillary buds, etc.) are different from that for in vitro. Nevertheless, genes and molecules recruited in the pathway of ex vitro development may interfere in the in vitro organogenesis.
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A Million Piece Jigsaw Puzzle: Transition Experiences of Foster Youth Accessing Higher Education through Community CollegeSullivan-Vance, Karen A. 14 June 2018 (has links)
A college education offers people social and economic benefits, yet youth from foster care backgrounds are less likely than their peers to attain a college education, which places this already vulnerable population at higher risk for a lifetime of living on the margins of society. Foster alumni face multiple obstacles to accessing and persisting in higher education. To facilitate and support the success of this frequently overlooked population, professionals in higher education need to understand these obstacles. Little is known about the experiences of youth with foster care backgrounds as they transition into and through higher education. Although existing research has reported the academic, health, and social effects of having been in foster care, little is known about why foster alumni do not persist in higher education. This study used student-development theory, specifically Schlossberg's transition theory, Tinto's theory of student departure, and Bourdieu's work on social and cultural capital to provide a conceptual framework through which to view the lived experiences of youth with foster care backgrounds. Because, for many youths with foster care backgrounds, the pathway to the baccalaureate degree is through a community college, this study examined and explored the transition experiences of foster alumni about to begin or currently enrolled at an Oregon Community College. The study explored the factors that challenge and facilitate foster alumni persistence towards the attainment of a college degree.
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Political Control and Accountability in Ethiopian RulemakingAraya, Esayas Kassa 01 January 2019 (has links)
Administrative rules have played a central role in Ethiopian public administration since 1994 when the current constitution was adopted. However, if the formulation and implementation of the rules are not politically controlled, and proper accountability is not applied, these same rules could become threats instead of assurances of the rule of law and order. This case study explored what strategic controls and accountability measures are in place to regulate the rulemaking process. To inform the study, the political control of bureaucracy framework in general and the principal-agency model, in particular, were used. The central research question focused on strategies that ensure the political control and accountability of rulemaking in Ethiopia. Purposive sampling methods were employed, with interviews of five legislators and five appointed officials, as well as supportive legislative documents providing the data. The data were coded and thematically analyzed using a coding framework and a continuous iterative process. The results revealed that in Ethiopia there is a constitutional framework of control and accountability, but there is no political control mechanism in place, and no accountability measures have been taken. The study findings may indicate that there is a need for further studies on administrative and judicial review mechanisms and federated states' control mechanisms to fully understand the situation. The implication for social change includes awareness and attitudinal change of lawmakers and administrative authorities towards the importance of controlling and limiting the power to make rules. Positive social change is nearly impossible where unlimited and uncontrolled power is exercised.
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Développement d’un modèle humain de mélanome ex vivo basé sur l’implantation de sphéroïdes dans des explants de peau / Development of a human ex vivo melanoma model based on the implantation of tumor spheroids into skin explantsJardet, Claire 11 October 2016 (has links)
Le mélanome métastatique est le cancer de la peau le plus agressif. Bien que son taux d’incidence soit inférieur à 1%, plus de 75% des décès associés à un cancer de la peau lui sont attribués. Au cours des dernières années, de nouvelles stratégies thérapeutiques ont permis d’améliorer la survie des patients. Cependant, des mécanismes de résistance à ces traitements se développent dans la majorité des cas, conduisant à une phase de rechute, et une survie à 5 ans inférieure à 20%. Des modèles d’étude expérimentaux sont nécessaires afin de comprendre les mécanismes impliqués dans l’apparition de ces résistances et développer de nouvelles stratégies thérapeutiques. Différents modèles in vitro sont actuellement utilisés pour le développement de drogues anti-tumorales, tels que celui du sphéroïde. Bien qu’il permette de reproduire l’organisation tridimensionnelle d’une tumeur, l’absence de microenvironnement tumoral empêche l’étude des interactions entre les cellules tumorales et celui-ci alors que ces facteurs jouent un rôle primordial dans la croissance tumorale et le développement de métastases. Dans ce contexte, mes travaux ont porté sur le développement et la caractérisation d’un modèle ex vivo de mélanome humain complet permettant l’étude de l’évolution d’une tumeur dans le tissu sain et l’évaluation de composés pharmacologiques. Les travaux réalisés ont tout d’abord conduit au développement d’un modèle de cancer cutané basé sur la combinaison d’un modèle de sphéroïde de lignée cellulaire de mélanome humain et du modèle de peau humaine ex vivo NativeSkin®, développé par la société Genoskin. Une procédure a été développée et validée pour permettre l’implantation reproductible d’un sphéroïde dans le derme des explants de peau. Parallèlement, j’ai développé une approche d’imagerie in situ par microscopie à feuille de lumière après transparisation des modèles. J’ai également développé une stratégie d’analyse d’images permettant la caractérisation quantitative de l'évolution du sphéroïde implanté en 3 dimensions et de suivre la dispersion des cellules du tumorales au sein de l’explant de peau. La caractérisation histologique du modèle implanté a révélé de façon très inattendue une perte progressive de l’intégrité du sphéroïde après implantation, associée à une diminution rapide de la prolifération des cellules le constituant et l’apoptose massive des cellules situées à sa périphérie. Ce phénomène a été observé de façon similaire lors de l’implantation de sphéroïdes produits à partir de différents types cellulaires. Afin de comprendre ces résultats, j’ai étudié l’implication potentielle de différents paramètres dans l’induction de la mortalité cellulaire observée tels que les conditions d’implantation, les facteurs synthétisés par le modèle et la contrainte mécanique exercée par le derme. Les résultats obtenus suggèrent que les facteurs sécrétés par les modèles après implantation du sphéroïde ont un effet antiprolifératif sur les sphéroïdes de mélanome et qu’ils induisent la mortalité des cellules situées à sa périphérie. Par ailleurs, l’application d’une contrainte mécanique extérieure sur les sphéroïdes de mélanome entraîne la perte de la cohésion de leur structure. Enfin, l’implantation de sphéroïdes dans le derme de biopsies de peau préalablement desséchées, induisant une perte de la viabilité cellulaire, a conduit à des résultats opposés à ceux observés avec de la peau normale : la structure des sphéroïdes reste cohésive et la prolifération des cellules est maintenue en périphérie du sphéroïde sans qu’aucune apoptose massive ne soit observée. L'ensemble de ces travaux semble suggérer que la mortalité du sphéroïde pourrait être, en partie, la conséquence d’une contrainte mécanique exercée par la peau sur le sphéroïde et/ou de facteurs produits par la peau durant sa culture. Ces données ouvrent des perspectives intéressantes dans le domaine de l’ingénierie tissulaire pour l’évaluation pharmacologique de composés thérapeutiques. / Malignant melanoma is the most aggressive form of skin cancer. Although it only occurs in less than 1%, it is responsible for more than 75% of skin cancer-related deaths. Furthermore, melanoma incidence has constantly increased during the last decades. New therapies such as targeted therapy and immunotherapy have emerged over the past years, significantly improving the overall survival rates of patients with advanced melanoma stages. However, resistance to those treatments develops in most cases, leading to relapse with a 5-years survival of those patients under 20%. Experimental models are needed in order to better understand the molecular events underlying these resistance mechanisms, and to develop new therapeutic strategies. MultiCellular Tumor spheroid is an increasingly recognized 3D in vitro model for pharmacological evaluation. Although this model accurately reproduces the 3D architecture, cell-cell interaction and cell heterogeneity found in microtumor in vivo, spheroids lack tumor-microenvironment interactions, which play a key role in tumor growth and metastasis development. In this context, the aim of my project was to develop and characterize a fully ex vivo human melanoma model for the study of tumor growth within the skin and the evaluation of antitumor drugs. Our approach relies on the combination of human melanoma cell lines grown in Multicellular Tumor Spheroids and the NativeSkin® model, an ex vivo human skin model produced by the biotechnology company Genoskin. Hence, I developed and validated a method to reproducibly implant one spheroid into the dermal compartment of skin explants cultured ex vivo. In parallel I have developed in situ imaging strategies based on light-sheet microscopy (SPIM, “Selective Plane Illumination Microscopy”) after optical clearing of the implanted skin biopsies. I also developed analytic methods to allow for the quantitative characterization of the spheroids evolution in 3 dimensions as well as tumor cells dispersal within the dermis of skin explants. Histological characterization of the implanted models over time revealed a progressive loss of the spheroids integrity after implantation associated with a rapid decrease in cell proliferation and massive apoptosis of the cells located in the peripheral layers. These results were shared by implanted spheroids made from different cell types. Further experiments were conducted in order to better understand these results and evaluate the impact of different parameters on the implanted microtumors viability such as the implantation procedure conditions, factors synthesized by the model after spheroid implantation and external mechanical stress. Results suggest that factors produced by the implanted models have an antiproliferative effect on melanoma spheroids and induce mortality in the peripheral layers of the spheroids. Moreover, results show that mechanical stress applied on melanoma spheroids induces loss of their cohesion. Finally, implantation of spheroids within the dermis of previously dessicated biopsies for 7 days, causing loss of skin cells viability, led to opposite results than in normal skin: spheroids maintain both a cohesive structure and proliferation in the peripheral cells without any massive apoptosis. Overall, this work led to the validation of a methodology to reproducibly implant spheroids into an ex vivo skin explant and the setup of an optical clearing technique necessary for in situ imaging of the implanted spheroid. Histological characterization unexpectedly revealed spheroids cells death following their implantation. Results suggest that this mortality could be partly related to mechanical stress exerted on the spheroids by the skin and/or by factors produced by the skin during culture. These data open new perspectives in the research field of tissue engineering for antitumoral pharmacology.
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Ex - dagseffekt : En studie kring avkastning på ex - dagen för utdelning / The Ex – day effect : A study about stock returns on the ex – day of dividend with the efficient market hypothesis in considerationIvansson, Richard, Viinikka, Janne January 2010 (has links)
<p>Question:</p><p>"Does the market possess perfect information as the efficient market hypothesis says?"</p><p>"Is there any significant relationship between the abnormal stock return on the ex – day and the dividend?" Purpose: The purpose of this study is to enlighten and find understanding about stock return versus dividend on the ex – day and try to figure out if abnormal returns occur on the portfolio during dividends.</p><p>Methodology:</p><p>The study was based in a quantitative nature and was derived with an event study and a hypothesis testing. The authors investigated the thirty most traded shares on the Stockholm stock exchange during a period of five years (2005 – 2009). They were analyzed during a total of nine days; the estimation window was set to sixty days. Theory: Leading theories in this field of study have been picked to enlighten and analysis the questions of the study. Theories used: Efficient market hypothesis, agent theory and the events of dividends.</p><p>Empiricism / Results:</p><p>The authors made an event study and hypothesis tested the information. From the data they could see a small abnormal return on every day except the day after the ex – day. However, they could not prove a significant relationship between the stocks return and the dividend.</p><p>Conclusion / Discussion:</p><p>The efficient market hypothesis was strengthened in the conclusion where all new information is reflected in the stock price because the null hypothesis was accepted in all nine cases. The authors also concluded that although they have a differentiated result compared to other studies, it could be a result of the recession. Another conclusion was that the relationship between shareholders and the management has been improved because of a better spread of information. </p>
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Ex - dagseffekt : En studie kring avkastning på ex - dagen för utdelning / The Ex – day effect : A study about stock returns on the ex – day of dividend with the efficient market hypothesis in considerationIvansson, Richard, Viinikka, Janne January 2010 (has links)
Question: "Does the market possess perfect information as the efficient market hypothesis says?" "Is there any significant relationship between the abnormal stock return on the ex – day and the dividend?" Purpose: The purpose of this study is to enlighten and find understanding about stock return versus dividend on the ex – day and try to figure out if abnormal returns occur on the portfolio during dividends. Methodology: The study was based in a quantitative nature and was derived with an event study and a hypothesis testing. The authors investigated the thirty most traded shares on the Stockholm stock exchange during a period of five years (2005 – 2009). They were analyzed during a total of nine days; the estimation window was set to sixty days. Theory: Leading theories in this field of study have been picked to enlighten and analysis the questions of the study. Theories used: Efficient market hypothesis, agent theory and the events of dividends. Empiricism / Results: The authors made an event study and hypothesis tested the information. From the data they could see a small abnormal return on every day except the day after the ex – day. However, they could not prove a significant relationship between the stocks return and the dividend. Conclusion / Discussion: The efficient market hypothesis was strengthened in the conclusion where all new information is reflected in the stock price because the null hypothesis was accepted in all nine cases. The authors also concluded that although they have a differentiated result compared to other studies, it could be a result of the recession. Another conclusion was that the relationship between shareholders and the management has been improved because of a better spread of information.
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