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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.
261

Perfil ontogenético da transcrição de subunidades do receptor N-Metil-D-Aspartato (NMDA) em estruturas cerebrais de ratos

Bock, Hugo January 2009 (has links)
O glutamato (Glu) é o neurotransmissor excitatório mais abundante do sistema nervoso central e está envolvido em funções cerebrais como aprendizado/memória, desenvolvimento e envelhecimento cerebral. Mudanças na vulnerabilidade neuronal durante o desenvolvimento pós-natal podem ser parcialmente explicadas por mudanças na expressão das subunidades de receptores de Glu (GluRs). O objetivo desse trabalho foi determinar o padrão de expressão das subunidades de GluRs do tipo N-metil-D-aspartato (NMDA) em quatro estruturas cerebrais (cerebelo, córtex, estriato e hipocampo) em diferentes estágios do desenvolvimento pós-natal de ratos por quantificação relativa por PCR em tempo real. Mudanças significativas na expressão de Grin1 foram observadas em quase todas as estruturas em relação aos níveis pós-natais de expressão. Níveis de expressão de Grin2A foram menores no cerebelo com um padrão de aumento gradual e níveis elevados na vida adulta no córtex e no hipocampo. A expressão do Grin2B demonstrou um padrão decrescente no cerebelo assim como no hipocampo. Por outro lado, o padrão de expressão de Grin2C mostrou uma tendência a aumentar nas quatro estruturas, a qual foi mais evidente no cerebelo com um aumento significativo nos níveis de expressão. O padrão de expressão do Grin2D foi também caracterizado por uma tendência para uma diminuição nos níveis de expressão pela vida adulta. Essa tendência foi mais evidente no cerebelo e no hipocampo. Expressões de Grin3A e Grin3B não demonstraram uma tendência específica. No caso de Grin3B, níveis semelhantes de expressão foram observados com a exceção de um pico de expressão no cerebelo de ratos de 10 dias. Os dados obtidos nesse estudo permitiram-nos introduzir novos aspectos na área de expressão de GluRs e poderão contribuir para desvendar potenciais alvos para o desenvolvimento de terapias mais efetivas para muitas doenças. / Glutamate (Glu) is the most abundant excitatory neurotransmitter of the central nervous system and is involved in cerebral functions such as learning/memory, development, and cerebral aging. The changes in vulnerability of neurons during postnatal development can be partially explained by changes in expression of glutamate receptors subunits (GluRs). In this work, we aimed to determine expression profile of ionotropic Nmethil- D-aspartate (NMDA) GluR subunits in four brain structures (cortex, cerebellum, striatum and hippocampus) in different stages of postnatal rat development by relative quantification real-time PCR using glyceraldehyde 3-phosphate dehydrogenase (Gapdh) as endogenous control. Significant changes in Grin1 expression were demonstrated in almost each age from all structures in relation to the initial postnatal expression level. Levels of expression of Grin2A were lower in cerebellum with a gradual raising pattern and high levels in adulthood in cortex and hippocampus. Grin2B expression levels were found to show a decreasing pattern in cerebellum as well as in hippocampus. Conversely, Grin2C expression pattern was found to show an increasing tendency in all four brain structures being more evident in cerebellum with significantly high expression levels. Expression profile of Grin2D was also characterized by a tendency to a drop in expression levels throughout adulthood. This tendency was well defined mainly in cerebellum and in hippocampus. Grin3A and Grin3B expression were found to show a non specific tendency. In the case of Grin3B, even levels of expression were seen with a marked exception of a peak in expression in cerebellum of 10-days old rats. Data generated in this study brings new insight in the field of GluRs expression and might contribute to unmask potential targets for the development of more effective therapies for many disorders.
262

A VARIATION ON MUTUALLY ORTHOGONAL LATIN SQUARES

Gunawardana, Beruwalage Lakshika Kumari 01 August 2016 (has links)
A Latin square of order n is an n × n array in which each row and column contains symbols from an n-set, S = {a1,...,an}, exactly once. If two Latin squares L1 and L2 of the same order can be joined such that each of the n^2 ordered pairs (ai,aj) appears exactly once, then L1 and L2 are said to be orthogonal. This project will involve a variation of this idea. We define orthogonality of two Latin squares Lm and Ln, for m < n, as follows: When we place an m × m Latin square Lm inside an n × n Latin square Ln, in all possible ways, the so obtained m^2 ordered pairs (ai,aj) are always distinct. We first investigate the situation when m = 2 and n = p, where p is a prime.
263

The manifestation of national identities in late eighteenth-century Scottish art, c.1750-1800

Graham, Deborah Jane January 2000 (has links)
This dissertation seeks to explore how national identities were manifest in eighteenth-century Scottish art. Understanding national identity to be a cultural and political phenomena, it considers symbols of national identity and examines in aesthetic and economic terms how the fine arts were both implicated in, and capable of expressing, the significant changes in national identity apparent in Scotland following the ’Forty-Five. The first chapter concerns itself with the issue of art and identity in Scotland between cl750 and 1800, and surveys the relevant literature, before introducing other significant issues pertinent to this research: the Enlightenment and Improvement. Chapter two recognises that previous studies of Highland portraits have examined them from an ‘external’ perspective. It investigates the implications of this for the viewer, and proceeds to analyse them from an ‘internal’ perspective intended to reveal the sitters’ motivations, to conclude that they are aristocratic images of authority, and its loss. The construction of the myth of the Highlands is thus expounded visually. If these symbols offer little evidence for an identity in flux, it is questionable whether individuals’ portraits can express national identity. Yet such a claim, it will be argued in chapter three, can be made through the desire to collect and order portraits by nation, and its relation to the Enlightenment discourse of the role of the individual in forming civil society. In this context, in chapter four, the aesthetic qualities of Allan Ramsay’s 1753-4 portraits will be argued as having been of particular significance to their Scottish sitters, being formed by Ramsay’s participation in Enlightenment Edinburgh society. Evidence for this position will be adduced through his paintings and writings, though the influence of physical setting is also considered. Finally, in chapter five, a study of Edinburgh art markets in comparison with those of English provincial cities addresses the question of whether Scotland was a nation, or province of England. The synthesis of existing literature and an original survey of art-related newspaper advertising reveals the Edinburgh market to be distinctive, though increasingly reliant upon London. The co-existence of local and national culture is found to be an important dialectic in the market, just as the dialectic between Scottish and British culture was found to be so generally in this dissertation. In conclusion, chapter six argues that while Scottish art must be considered as part of the history of British art, the desire amongst Scots to be part of a British nation was a significant force in shaping Scottish visual culture.
264

Contemporary literary theory: a critique of Saule's three isiXhosa novels, Unyana womntu, Umlimandlela and Ukhozi olumaphiko

Duka, M. M.,(Minsie Meshach),1948- 30 November 2001 (has links)
African languages / D.Litt. et Phil.
265

Women, representation and the spiritual in the works of Thomas Cooper Gotch, Robert Anning Bell and Frederick Cayley Robinson

Eden, Alice January 2016 (has links)
This thesis examines the works of three ‘forgotten’ British artists, working from the late nineteenth century and well into the 1920s. In a period which saw momentous changes associated with the onset of modernity, artworks appeared to speak of revivalism, tradition, even nostalgia, rather than the new. Thomas Cooper Gotch, Robert Anning Bell and Frederick Cayley Robinson shared an interest in the spiritual, the unseen and immaterial, which they expressed through representations of women, placing faith, broadly, in ‘the feminine’ as synonymous with humanity’s neglected ‘spirit’ in the modern, materialistic world. The eclectic and contradictory nature of the artworks examined, their complex and ambiguous representations of womanhood and female spirituality were expressive of the condition of modernity in its rich, varied forms. These artworks are analysed in the context of an important historical moment for the feminist movement, since all three artists addressed the explosion in female agency related to contemporary feminism, the ‘gender crisis’ and the Suffragette movement. By placing artworks in this context, I have attempted to bring women, their presence in the public sphere and visual culture, their discovery of a ‘feminist voice’ in this period, into the frame. Women imagined invigorating movements, from the confines of the domestic interior into the airy heights of mountain tops, using languages of righteousness and joyous expectancy, and the artworks examined provide visual analogues and commentaries on these feminist possibilities and new imaginative aspirations. While all three artists mediated the visual ‘types’ of womanhood available within art languages, they created quite distinct images of women. Representations range from Gotch’s female Messiah, where woman’s spiritual power originates in her innocence and purity, Bell’s images of Amazonian strength allied with a closer female relationship with nature, to more occult versions in Cayley Robinson’s paintings, related to theosophy. The artworks participated in a tremendous moment of hope for women in their endeavours toward autonomy and fulfilment. In presenting women’s spiritual role as humanity’s redeemer, these paintings reveal how art may envisage intangible forms of spirituality and emancipatory possibilities.
266

Cultural depictions of the European fallow deer (Dama dama) 6000 BCE to 1600 CE

Ward, Christopher January 2017 (has links)
This thesis will seek to illustrate the social and cultural role which the European Fallow Deer has played in the period 6000 BCE – 1600 CE by investigating cultural depictions of the animal. These cultural depictions take various forms, in material culture, iconography and literary works as well as in its conceptions and classifications. Taking specific examples of practices throughout the eras, each will be examined in regard to the historical, cultural and ecological contexts and the fallow deer itself. Although many depictions, especially from earlier eras would appear scant, and later depictions are very geographically and culturally specific, the perception of the deer by cultures is a worthwhile and meaningful exploration. This present work gives particular attention to the ancient Greeks, the Thracians, the Romans, and the medieval British, who all appeared to invest heavily in the species and in its cultural depictions and movements. Depiction of fallow deer will be discussed from the Neolithic period, through the medieval until the 17th century at around the time the medieval emparkment and sovereignty systems ended. Whilst fallow deer has become a staple for the many deer parks of Europe, and has been introduced across the world, historical research into the human approaches and efforts shown towards the animal by species and classifications has been minimal. As part of an AHRC funded project, this species of deer has been subject to intensive study. It is hoped that this research will complement the project’s work and that a better understanding of the human perception and efforts regarding the animal may be attained.
267

Síntese e análise estrutural de novos ciclopaladatos e síntese de N-heterociclos a partir de ciclopaladatos e alenos

Zanini, Mara Lise January 2002 (has links)
Os compostos de paládio vêm apresentado uma vasta linha de aplicação, tanto como catalisadores como precursores em reações de síntese orgânica. Dentre esses compostos, os ciclopaladatos, que são compostos cíclicos com uma ligação Pd-heteroátomo, permite a formação de novas estruturas cíclicas contendo algum heteroátomo, como nitrogênio, oxigênio ou enxofre. Neste trabalho foram sintetizadas aminas propargílicas capazes de se coordenar a sais de paládio, formando novos ciclopaladatos através da reação de cloropaladação. Esses compostos se encontram na forma de dímeros e podem apresentar-se como diferentes isômeros. Estudos espectroscópicos, tais como RMN de 1H, 13C e raios-X de monocristais foram realizados para a elucidação estrutural desses novos compostos. Além dos isômeros geométricos clássicos (cisóide e transóide) foram observados pela primeira vez a formação de atropoisômeros. Esses ciclopaladatos, contendo nitrogênio ligado ao paládio, foram testados frente a alenos diferentemente substituídos, mostrando que ocorre a inserção do aleno na ligação Pd-C e, seguido da depaladação, ocorre a formação de novos compostos heterocíclicos a seis membros. Alguns ciclopaladatos, quando em solução, podem apresentar certa instabilidade, ocorrendo a decomposição do ciclopaladato com a regeneração do alcino precursor do respectivo ciclopaladato. Assim, estudou-se a reação de decomposição de diferentes ciclopaladatos, chamada de retrocloropaladação, utilizando a técnica de RMN de 1H em diferentes intervalos de tempo. / Palladium compounds have application in different fields, such as catalysis or as precursors in organic synthesis reactions. Among these compounds, the palladacycles, which are cyclic compounds with a Pdheteroatom bond, allow the formation of new cyclic structures with at least one heteroatom such as nitrogen, oxygen or sulfur. In this work, propargylic amines were synthesized, which are capable to coordinate with palladium salts, affording new palladacycles by chloropalladation reactions. These compounds are dimers and can be present as different isomers. Spectroscopic analyses, such as 1H, 13C NMR and X-Ray of monocrystals were performed in order to elucidate the structure of these new compounds. Besides the classic geometric isomers (cisoid and transoid) for the first time the formation of atropisomers was observed. This palladacycles, with nitrogen bonded to palladium, were tested with different substituted allenes and showed the insertion of allene into the Pd-C bond. Subsequent depalladation resulted in the formation of new six member heterocycles. Some palladacycles are not stable in solution and undergo decomposition reactions yielding the alkyne precursors of palladacycle. We have studied these decomposition reactions of different palladacycles, called retro-chloropalladation, using 1H NMR analysis at different time intervals.
268

Perfil ontogenético da transcrição de subunidades do receptor N-Metil-D-Aspartato (NMDA) em estruturas cerebrais de ratos

Bock, Hugo January 2009 (has links)
O glutamato (Glu) é o neurotransmissor excitatório mais abundante do sistema nervoso central e está envolvido em funções cerebrais como aprendizado/memória, desenvolvimento e envelhecimento cerebral. Mudanças na vulnerabilidade neuronal durante o desenvolvimento pós-natal podem ser parcialmente explicadas por mudanças na expressão das subunidades de receptores de Glu (GluRs). O objetivo desse trabalho foi determinar o padrão de expressão das subunidades de GluRs do tipo N-metil-D-aspartato (NMDA) em quatro estruturas cerebrais (cerebelo, córtex, estriato e hipocampo) em diferentes estágios do desenvolvimento pós-natal de ratos por quantificação relativa por PCR em tempo real. Mudanças significativas na expressão de Grin1 foram observadas em quase todas as estruturas em relação aos níveis pós-natais de expressão. Níveis de expressão de Grin2A foram menores no cerebelo com um padrão de aumento gradual e níveis elevados na vida adulta no córtex e no hipocampo. A expressão do Grin2B demonstrou um padrão decrescente no cerebelo assim como no hipocampo. Por outro lado, o padrão de expressão de Grin2C mostrou uma tendência a aumentar nas quatro estruturas, a qual foi mais evidente no cerebelo com um aumento significativo nos níveis de expressão. O padrão de expressão do Grin2D foi também caracterizado por uma tendência para uma diminuição nos níveis de expressão pela vida adulta. Essa tendência foi mais evidente no cerebelo e no hipocampo. Expressões de Grin3A e Grin3B não demonstraram uma tendência específica. No caso de Grin3B, níveis semelhantes de expressão foram observados com a exceção de um pico de expressão no cerebelo de ratos de 10 dias. Os dados obtidos nesse estudo permitiram-nos introduzir novos aspectos na área de expressão de GluRs e poderão contribuir para desvendar potenciais alvos para o desenvolvimento de terapias mais efetivas para muitas doenças. / Glutamate (Glu) is the most abundant excitatory neurotransmitter of the central nervous system and is involved in cerebral functions such as learning/memory, development, and cerebral aging. The changes in vulnerability of neurons during postnatal development can be partially explained by changes in expression of glutamate receptors subunits (GluRs). In this work, we aimed to determine expression profile of ionotropic Nmethil- D-aspartate (NMDA) GluR subunits in four brain structures (cortex, cerebellum, striatum and hippocampus) in different stages of postnatal rat development by relative quantification real-time PCR using glyceraldehyde 3-phosphate dehydrogenase (Gapdh) as endogenous control. Significant changes in Grin1 expression were demonstrated in almost each age from all structures in relation to the initial postnatal expression level. Levels of expression of Grin2A were lower in cerebellum with a gradual raising pattern and high levels in adulthood in cortex and hippocampus. Grin2B expression levels were found to show a decreasing pattern in cerebellum as well as in hippocampus. Conversely, Grin2C expression pattern was found to show an increasing tendency in all four brain structures being more evident in cerebellum with significantly high expression levels. Expression profile of Grin2D was also characterized by a tendency to a drop in expression levels throughout adulthood. This tendency was well defined mainly in cerebellum and in hippocampus. Grin3A and Grin3B expression were found to show a non specific tendency. In the case of Grin3B, even levels of expression were seen with a marked exception of a peak in expression in cerebellum of 10-days old rats. Data generated in this study brings new insight in the field of GluRs expression and might contribute to unmask potential targets for the development of more effective therapies for many disorders.
269

Taming transgression : Dionysos in the arts of the modern era

Massini, Alexandra January 2016 (has links)
The topic of my research is the irrational and the ways it was accommodated through the visual arts of the modern era. In particular, I explore this theme through the relationship between Dionysos and Apollo. Ever since Nietzsche's 'Die Geburt der Tragodie' (1872), the polarity of the two gods has been codified in Western culture. Yet while their discrepancy as opposites has been widely discussed, they are two sides of the same coin, sharing similar traits since Antiquity. Beginning with an introduction on the cultural climate of the nineteenth-century, I argue that Nietzsche's principles had been anticipated by the exponents of German Romanticism and found earlier sources in the Humanism of fifteenth-century Italy, when Plato's writings in praise of 'madness' were rediscovered. While investigating significant aspects of Western cultural heritage, I trace the sources of Nietzsche's ideas, confronting these with examples from the visual arts. To this end, I first re-consider the ancient Dionysos and his transformation in the Middle Ages. I then analyse which aspects of the god were favoured in the Renaissance and which Dionysian narratives were re-produced. Within this framework, I assess the multifaceted character of the god and the meanings he acquired according to different periods, places and requirements. `Bacchus, id est vinum' recites a popular formula, but from Michelangelo to Caravaggio and beyond, this was not the only Dionysian guise to be known in the modern era. While often represented as a merrymaking god of nature, either alone or participating in Bacchanals and his Triumphs, darker aspects could be chosen to represent his world. It is the madness and disorder, as well as the reasons for their revelation (or omission) in specific contexts that I explore, in the belief that they provided the roots for Nietzsche's dualistic formulations and many a modern coniunctio oppositorum.
270

Shamanarchy : the life and work of Jamie Macgregor Reid

Maguire, Vicki January 2010 (has links)
No description available.

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