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O papel da enzima Na+,K+-ATPase no déficit cognitivo e no efeito profilático induzido pelo exercício físico após o Traumatismo Crânio-Encefálico / The role of Na+,K+-ATPase enzyme on cognitive deficit and in the prophylactic effect induced by exercise after Traumatic Brain InjuryLima, Frederico Diniz 17 September 2009 (has links)
Traumatic Brain Injury (TBI) is the major cause of death or cognitive deficits in industrialized countries. Although studies have indicate that the oxidative stress and functional deficits after TBI are connected events, the mechanisms that outline the development of these cognitive deficits are, still, limited. In this context, we
investigated the involvement of oxidative stress markers (thiobarbituric acid reactive species; TBARS and protein carbonylation) and the Na+,K+-ATPase enzyme activity
on the spatial learning after one and three months from a fluid percussion injury (FPI) in rats. The results revealed that FPI increase the latency of escape and the number of the errors on the Barnes Maze Test one and three months after FPI. We also found an increase of TBARS and protein carbonylation in parietal cortex after one and three months FPI. In addition, statistical analysis revealed a decrease of the Na+,K+- ATPase enzyme activity in the parietal cortex after FPI (time-dependent). These
results suggest that cognitive impairment following FPI may result, at least in part, from increase of two oxidative stress markers, protein carbonylation and TBARS that occurs concomitantly to a decrease in Na+,K+-ATPase activity. Physical exercise, despite the involvement on the generation of the reactive oxygen species (ROS), is
used on the rehabilitation of TBI. However, although the favorable effects of physical exercise on traumatic brain injury (TBI) patients is well known, the specific
mechanisms involved in this protection after TBI has been limited. Thus, we investigated whether physical training protects against oxidative damage (measured by protein carbonylation and TBARS) and neurochemical alterations represented by immunodetection of alpha subunit and activity of Na+,K+-ATPase after FPI in cerebral cortex of rats. The results revealed that physical training protected against oxidative damage induced by FPI. In addition, physical training was effective against Na+,K+-
ATPase enzyme activity inhibition and α subunit level decrease after FPI. The Pearson correlation showed that the decrease of the catalytical levels of the Na+,K+-
ATPase enzyme α subunit is related with the increasing on oxidative stress markers. Moreover, the physical activity-related protection against free radicals induced by FPI
links with maintenance of α subunit immunocontent. These results suggest that the effective protection stimulated by physical exercise on the neuronal damage induced
by TBI has connection with the protection of the specific targets from the free radicals action, like Na+,K+-ATPase enzyme. / O Traumatismo crânio-encefálico (TCE) é uma das maiores causas de morte ou déficits cognitivos nos países industrializados. Apesar de os estudos indicarem que o
estresse oxidativo e os déficits funcionais que ocorrem após TCE serem eventos interrelacionados, os mecanismos que delineiam o desenvolvimento destes déficits cognitivos
são, ainda, limitados. Neste contexto nós investigamos o envolvimento de marcadores de estresse oxidativo (espécies reativas ao ácido tiobarbitúrico; TBARS e carbonilação
protéica) e a atividade da enzima Na+,K+-ATPase no aprendizado espacial um e três meses após um dano de percussão por fluído (FPI) em ratos. Os resultados revelaram que o FPI aumentou o tempo de latência e o número de erros no teste do labirinto de Barnes em um e três meses após FPI. Também encontramos aumento no conteúdo de TBARS e proteína carbonil no córtex parietal em um e três meses após FPI. Além disso, a análise estatística revelou uma diminuição na atividade da enzima Na+,K+-ATPase no córtex cerebral após FPI tempo dependente, sugerindo que o déficit cognitivo induzido pelo FPI se deva pela perda de funcionabilidade de enzimas presentes na células como Na+,K+-ATPase. Perda esta induzida pelo aumento na geração de radicais livres após TCE. Apesar de estar envolvido no aumento da produção de espécies reativas ao Oxigênio (ERO), exercício físico tem sido
utilizado na reabilitação de após TCE. Por outro lado, ainda são escassos na literatura estudos que evidenciam a especificidade dos mecanismos envolvidos na proteção induzida pelo exercício físico após TCE. Desta forma, investigamos se o treinamento físico protege contra o dano oxidativo bem como das alterações neuroquímicas representadas pela imunodetecção da subunidade α e da atividade da enzima Na+,K+-ATPase no córtex cerebral de ratos. Os resultados revelaram que o treinamento físico protegeu contra o dano oxidativo induzido por FPI. Além disso, o treinamento físico foi efetivo contra a inibição da
enzima Na+,K+-ATPase e a diminuição dos níveis da sua subunidade α após FPI. A correlação de Pearson revelou que a diminuição dos níveis catalíticos da subunidade α da
enzima Na+,K+-ATPase se correlaciona com o aumento dos marcadores de estresse oxidativo. Além disso, a proteção exercida pela atividade física contra os radicais livres
induzidos por FPI tem relação com a manutenção do imunoconteúdo da subunidade α. A partir destes achados, sugere-se que a efetiva proteção exercida pelo exercício físico no dano neuronal causado induzido pelo TCE se deva pela proteção de alvos específicos a ação de radicais livres, como a enzima Na+, K+-ATPase.
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Modernism and the queer : Djuna Barnes/Gertrude SteinShin, Ery January 2013 (has links)
Djuna Barnes and Gertrude Stein may appear unrelated to one another at first glance. We have an impoverished upstate New Yorker versus relatively comfortable Californian, bisexual romantic nomad versus lesbian monogamist, nihilist versus life-affirming enthusiast, and agnostic-atheist versus secular Jew. When they are referenced together (which happens rarely), it is usually in the context of their Parisian exploits. But a closer look reveals more vital affinities. Both writers remain problematically situated in the modernist canon. Both were inspired by visual art. Both struggled to get published during their lifetimes. Both disassociated themselves from mainstream feminist movements, preferring subtler, more idiosyncratic ways of questioning the status quo. Both held a sustained interest in the queer and, as this dissertation seeks to demonstrate, imagined that theme in original ways—Barnes, through loss; Stein, through phenomenology. Writing out of the spirit of Christian martyrdom, Barnes revels in queer suffering and its transfiguring potential: queers extravagantly lose (themselves), fail, and suffer, yet such ordeals aren’t without value. The first half of my dissertation, thus, appraises Barnes’ “queer negativity” in general before pondering how its masochistic energies push against those authorities that would negate the queer. Chapter One analyzes Barnes’ mythical-seeming transgendered figures who encounter profound failure, despite the imaginative freedom emanating from their ahistorical surroundings. Barnes’ sense of queer failure intensifies in Chapter Two, where same-sex desire invokes the abject by symbolically collapsing psychic boundaries between lovers and refusing reproductive futurity. Both chapters contextualize the moral inversion that becomes the focus of Chapter Three: how does such nihilism tragically ennoble the queer and endow it with insurgent impulses? Without taking a self-consciously queer activist stance, Barnes draws on what Gilles Deleuze would later enunciate as an inverted affect regime: the power of punishment to enforce repressive sexual regulations through pain and hence to bridle perversion becomes inverted when punishment opens the portal to pleasure, when pleasure relocates to sites of perversion. If Barnes writes as a romantic martyr, Stein looks at the queer through a phenomenologist’s eyes. The reciprocity between social conditioning and consciousness, in particular, remains an urgent concern throughout her career. To be “queer,” one often breaks away from a lifetime of habituated orientations toward sex and gender. But queerness cannot wholly bracket the norms that have been left behind. It exists in relation to what it queers. Foregrounding this discussion, Chapter Four examines how Stein’s modernism, phenomenology, and queer criticism intersect. Chapter Five investigates how “Miss Furr and Miss Skeene,” “Many Many Women,” and The Making of Americans reorient us from the “straight” and narrow. Yet this reorientation remains partial. Not all heteronormative biases can be shed, as is evident in The Making of Americans’ classist undertones running through its “singular” queer vision. The sixth chapter further tests the limits of reorientation as such. Ida’s Ida desperately wants to live a queer life, but discovers that she cannot if she approaches queerness as a radically separatist ideal. A solipsistic universe where she can entirely withdraw from society through sleep, silence, or soliloquy remains a fantasy. Ida’s internal conflict, in turn, mirrors Stein’s struggle to enact aesthetic modes that prove just as impossible to practice, being devoted to eliminating memory, emotions, personal identity, and social awareness.
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Endocannabinoid Modulation of Spatial Memory in Aversively and Appetitively Motivated Barnes Maze TasksHarloe, John Pinckney 01 January 2008 (has links)
Genetic deletion or pharmacological blockade of the CB1 receptor has been reported to impair extinction learning in aversive conditioning (i.e., conditioned fear and Morris water maze) paradigms, but not in operant procedures in which food reinforcement is earned. It is difficult to discern whether the differential effects caused by CB1 receptor disruption on extinction result from the hedonics (i.e., aversive vs. appetitive) or is related to the required responses associated with these disparate tasks. In order to evaluate whether the hedonics is the determining factor, we used either aversive (i.e., escape from bright lights and air turbulence) or appetitive (i.e., to gain access to water) motivators in the Barnes maze task, a model in which mice are required to enter a hidden goal box. Administration of the CB1 receptor antagonist, rimonabant, disrupted extinction learning under aversive conditions, but not under appetitive conditions. This is the first study to show a differential effect of rimonabant on extinction in a task that required identical motor behaviors, but only differed in hedonic nature of the reinforcer. In addition, genetic ablation of CB1 receptor signaling impaired acquisition of the task under both aversive and appetitive conditioning procedures. Conversely, enhancing endocannabinoid signaling, via genetic deletion of the FAAH enzyme, accelerated acquisition of the task under aversive, but not appetitive, conditioning procedures. Accordingly, these data strongly support the hypothesis that the endogenous cannabinoid system plays a necessary role in the extinction of aversively motivated behaviors, but is expendable in appetitively motivated behaviors. While these findings underscore concerns over potential side effects associated with CB1 receptor antagonists, they also suggest that stimulating the endogenous cannabinoid system may be a promising pharmacological approach to treat maladaptive behaviors that arise from stress or trauma.
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Ghost words and invisible giants : H.D. and Djuna Barnes under signs of the imperativeDustin, Lheisa 23 May 2017 (has links)
My dissertation examines the correlations between the natural and supernatural, agency and authority, and meaning and language in the work of the modernist American writers H.D. (Hilda Doolittle) and Djuna Barnes. Using the psychoanalytic theory of Jacques Lacan, Melanie Klein, and Nicholas Abraham and Maria Torok, I argue that the different kinds of spectral and otherworldly figures that appear in these works – ghosts, the living dead, divinities, individuals who are also amorphous multiplicities – correlate to the modes of negation of parental imperatives that structure the language-use of their authors. I contrast H.D.‘s and Barnes‘s visions of the relation of language to meaning and the personal to the social using Lacan‘s delineation of the different modes of psychic negation that enable or disable language use: repression, disavowal, and foreclosure. According to this model, H.D.‘s work evidences foreclosure: a mode of thought and language that fails to differentiate words, thoughts, and people from one another. This incapacity endangers the psyche with the hallucinatory return of or haunting by what cannot be symbolized. In contrast, Barnes‘s work suggests disavowal, and her language renders experience in distorted forms. She repudiates power figures and the unspeakable meanings associated with them, but her work portrays the spectral, surreptitious return of these figures and meanings.
Writing that witnesses or stages a return to a state of non-difference between symbol and symbolized, as Barnes‘s and H.D.‘s work does, calls for different interpretative and methodological strategies than those usual in literary criticism. To read such work primarily as symbolic communication is to lose perspective on the structures of thought and language that it grapples with. A perspective that is rigorous and radically different from the works‘ own is necessary to produce readings of it that make symbolic ―sense,‖ though it is unable to fully account for experiences that are not conceivable. To this end, I describe ―disorders,‖ types of thought and language that psychoanalysis implicates in interminable human suffering, without drawing conclusions about the range of experiences that might be concurrent with asymbolic or anti-symbolic thought and writing. / Graduate / 2019-08-31 / 0298 / 0591
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Writers & typists: intersections of modernism and sexologyJenkins, Brad 30 August 2007 (has links)
This study explores the intersection of Modernism and sexology. To date, most studies of sexology’s influence on literature have focused on the importance of inversion in the lesbian salons of interwar Paris and, specifically, on Radclyffe Hall and her associates. The central question in these studies is whether inversion was ultimately beneficial or detrimental to the larger struggle for sexual equality and gay rights. This is an important question and key elements of the debate are reviewed. Sometimes lost in this discussion, however, is sexology’s influence on the creative process of different Modernist writers. By purporting to explain the origins and function of desire, sexology raised the prospect of engineering response, of literally seducing the reader into new aesthetic experiences. These prospects arise not from a literal application of sexological precepts but from a process of critical revision that transformed sexology without undermining the objectivist pretensions upon which the discourse was founded. The dissertation is directed toward explaining the nature of this exchange and its influence on the work of Gertrude Stein, Virginia Woolf, and Djuna Barnes.
Theoretically, the study follows Bruno Latour in rethinking the arts/science divide. It suggests writers were able to occupy seemingly self-contradictory positions—embracing both the objective authority of science and the perspectivism of the arts—by exploiting a disavowed hybridity at the heart of the modern condition. This discursive sleight of hand empowered these writers to reinvent both their own identities and the forms in which they worked. Proceeding more or less chronologically, the study begins by looking at Gertrude Stein’s efforts to incorporate the mechanics of attraction into her writing, guided by the work of Otto Weininger. It next examines Virginia Woolf’s exploration of androgyny with reference to Edward Carpenter’s advocacy on behalf of the “intermediate sex”. Finally, attention shifts to Djuna Barnes and the limits of sexology and other attempts to theorize desire. Ultimately, the goal is not to explain sexual difference or to advocate on behalf of any one position. Instead, the dissertation examines how sexology inspired the Modernist imagination in further challenging artistic conventions.
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Investigação dos sintomas iniciais da doença de alzheimer em ratos wistar submetidos à infusão intracerebral de peptídeos amilóides e do potencial neuroprotetor do extrato de erythrina velutina por meio do labirinto de barnesMacêdo, Priscila Tavares 30 January 2018 (has links)
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Previous issue date: 2018-01-30 / A doença de Alzheimer (DA) afeta cerca de 46,8 milhões de pessoas no mundo, e é
caracterizada pelo declínio progressivo da função cognitiva, em especial da memória
episódica. É multifatorial, e o acúmulo de peptídeos β-amiloides (Aβ) é considerado o
principal mecanismo da neurodegeneração subjacente à doença. Os Aβ são os principais
componentes das placas amilóides, um dos marcos fisiopatológicos no encéfalo dos
pacientes. A infusão intracerebral de Aβ em ratos é um modelo animal de DA muito
utilizado, produzindo seu acúmulo em regiões cerebrais afetadas, como o hipocampo e o
neocórtex e, produzindo déficits cognitivos compatíveis com os sintomas, como déficits
na memória espacial. Porém, a maioria dos estudos evidencia déficits equivalentes aos
estágios moderado e avançado da DA após a infusão prolongada de Aβ, sem avaliar
déficits sutis de estágios iniciais. Isso seria relevante para compreensão dos mecanismos
fisiopatológicos e para o teste de possíveis tratamentos neuroprotetores. Uma tarefa
utilizada para avaliar déficits relacionados à disfunção hipocampal em ratos é o labirinto
de Barnes. Os animais são expostos a uma plataforma circular, com buracos ao redor,
sendo apenas um deles conectado a um esconderijo. Nessa tarefa, os animais guiam-se
por pistas distais para encontrar o local seguro. O desempenho é avaliado por parâmetros,
como latência e distância até o alvo, número de visitas a buracos errados, dentre outros,
e por uma análise específica de estratégias de busca usadas para atingir o alvo. O animal
pode se localizar pelas pistas distais (dispostas ao redor do labirinto), utilizando
informação espacial (estratégia direta) ou outros tipos de busca, visitando de maneira
aleatória ou seriada buracos do aparato (estratégias não diretas). Essa avaliação permite a
detecção de alterações no modo de solução da tarefa. No presente trabalho, objetivamos
investigar sinais cognitivos iniciais da DA em ratos Wistar submetidos à infusão
intracerebral de Aβ, e os efeitos de um potencial tratamento neuroprotetor, por meio da
avaliação da memória espacial no labirinto de Barnes. Utilizamos o extrato alcalóide de
Erythrina velutina (“mulungu”), cujos componentes mostram ações ansiolíticas, antiinflamatórias,
antioxidantes e pró-colinérgicas. Na 1ª etapa, padronizamos a tarefa de
Barnes para as nossas condições experimentais, e verificamos se há influência da
repetição de exposições ao labirinto (importante para verificação de progressão de sinais
cognitivos) ou da implantação das cânulas intracerebrais no desempenho dos animais.
Animais que passaram ou não pela cirurgia para implantação de cânulas (bilateralmente
na sub-região hipocampal CA1 e no ventrículo lateral) passaram por 5 sequências de
exposição ao labirinto de Barnes (4 treinos com 4 trials cada, um teste após 24h e um
teste após 10 dias). Os resultados mostraram que houve aprendizado e evocação da tarefa.
Concluímos que a tarefa pode ser realizada repetidamente, e em animais com implantes
cerebrais de cânulas, sem prejuízo de desempenho. Na segunda etapa, investigamos o uso
de diferentes estratégias no labirinto de Barnes na presença ou ausência de pistas distais.
Ratos foram expostos aos treinos no labirinto de Barnes, e no teste (24h após) parte dos
animais foi exposta ao labirinto na presença de pistas distais (condição ‘espacial’) e a
outra parte passou pelo teste com uma cortina preta em volta do labirinto (condição ‘nãoespacial’).
Ambos os grupos aprenderam e evocaram a tarefa, entretanto os animais
expostos às pistas distais preferiram o uso de estratégia direta, enquanto o grupo nãoespacial
preferiu outras estratégias. Concluímos que a retirada de pistas distais não
impede que os animais encontrem o alvo, e para isso utilizam estratégias de busca
alternativas ao uso de informação espacial. Na terceira etapa (2 experimentos)
verificamos os efeitos da infusão intracerebral de peptídeos Aβ sobre o aprendizado e a
memória no labirinto de Barnes. No experimento 1, ratos receberam 15 infusões diárias de salina ou Aβ (30, 100 ou 300 pmol) i.c.v., sendo que no 1º dia de tratamento houve
infusões em CA1. Foram submetidos a 3 sequências de exposição ao Barnes (treinos,
teste 24h e reteste 10 dias). A sequência I foi realizada antes da cirurgia (na qual ocorreu
o aprendizado para todos os animais), a II a partir da 11ª infusão, e a III 10 dias depois.
Nas sequências II e III, houve grande variação do comportamento dos animais Aβ, de
modo que não foram observadas diferenças entre os grupos, além de uma alta mortalidade
dos animais. Ao fim dos experimentos comportamentais, os animais foram eutanasiados
e submetidos à imunohistoquímica para Aβ, cuja análise por densitometria ótica relativa
mostrou aumento de sua marcação no hipocampo e neocórtex. No 2º experimento
verificamos os efeitos da infusão de Aβ sobre o desempenho geral e estratégias de busca
no labirinto de Barnes, com algumas alterações no protocolo de infusão e execução da
tarefa. Os animais (salina ou Aβ 30 pmol) foram submetidos a uma sequência de
exposição ao Barnes com 4 treinos de 2 trials cada e um teste realizado 3 dias depois,
visando dificultar a tarefa. Não houve diferenças entre os grupos no aprendizado. No
teste, embora os animais Aβ mostrassem alguma evocação, estes utilizaram
preferencialmente estratégias aleatória e seriada, enquanto o grupo salina preferiu a
estratégia direta. Concluímos que a infusão de Aβ promoveu alterações sutis na memória
espacial compatíveis com a manifestação inicial da DA, indicando relevância para
investigações mecanicísticas e terapêuticas em estágios precoces da doença. Na última
etapa, animais submetidos ao mesmo tratamento de infusão com Aβ (30 pmol) foram
tratados concomitantemente com 200 mg/kg do extrato de mulungu por via oral. Os
grupos (salina, Amulungu e Amulungu) foram submetidos a 2 sequências de
Barnes (a partir da 11ª infusão e dez dias depois). De forma geral, não foram observadas
diferenças entre os grupos nos parâmetros referentes ao aprendizado ou à evocação da
tarefa. Sendo assim, concluímos que o protocolo utilizado não foi capaz de detectar um
efeito benéfico do extrato de mulungu no modelo de DA por infusão de peptídeos Aβ. / Alzheimer’s disease (AD) is present in 46.8 million people in the world, and is
characterized by the progressive decline of cognition, mainly episodic memory. AD is
multifactorial, and the accumulation of amyloid peptides (Aβ) is the main proposed
mechanism underlying neurodegeneration. Aβ are the main components of the amyloid
plaques in the brain, that are physiopathological hallmarks of the disease. Intracerebral
infusion of Aβ in rats is usually used as an animal model of DA and generates the
accumulation of these peptides in the brain together with spatial memory impairment.
However, most studies show moderate to severe deficits after chronic Aβ infusion,
without evaluation of possible subtle initial deficits. The study of the initial stages of AD
is relevant for mechanicistic and therapeutic investigations. The Barnes maze has been
used for investigating deficits in the hippocampal function in rats. The animals are
exposed to a circular apparatus with holes in its periphery. One of the holes is connected
to a safe place. In this task, rats navigate guided by distal cues to find this safe
compartment. The evaluation is conduct by parameters of general performance (latency
and distance to reach target, number of errors, among others) and by a specific analysis
of search strategies. In this way, the animal use spatial information and move directly
towards the target (direct strategy), visit sequential holes until reach the target (serial
strategy) or visit holes in a non-systematic fashion until reach the target (aleatory search).
The analysis of strategies allows the detection of alterations in the mode of solution of
the task. In the present study, we aimed to investigate initial cognitive signs of AD in
Wistar rats submitted to intracerebral infusions of Aβ, as well as the effects of a
potentially neuroprotective treatment, by the evaluation of spatial memory in the Barnes
maze. We used the alkaloid extract of Erythrina velutina (“mulungu”), which was
previously studied for anxiolytic, anti-inflammatory, antioxidant and cholinergic actions.
First, we standardized the task to our experimental conditions, and verified a possible
influence of repeated expositions to the apparatus (for future long-term protocols) or of
the implantation of the cannulas in the brain. Rats went through (or not) to implantation
of cannulas (bilaterally in the hippocampal CA1 and in the lateral ventricle) and were
exposed to 5 sequences of exposition to the Barnes maze (4 trainning sessions with 4
trials each, a 24h test and a 10-day retest sessions). Both groups showed task retrieval,
and there was a slightly improved performance in the implanted group. We concluded
that the task can be held repeatedly, and in implanted animals, without altering the
performance. In the second phase, we investigated the use of different strategies in the
Barnes maze by rats submitted to the presence of absence of distal cues. Rats were
exposed to the training phase, and in the probe session (24 h later) half the animals were
exposed to the maze in the presence of the same distal cues used in training (spatial
group), while the other rats went through the probe test without those cues (a black curtain
was placed around the maze – non-spatial group). Both groups learned the task, but the
spatial group preferred the used of direct strategies, while the non-spatial group preferred
other strategies. We concluded that the removal of distal cues does not hinder the
execution of the task, and the animals use alternative search modes under this condition.
In the third phase (two experiments) we verified the effects of the intracerebral infusion
of Aβ on the acquisition and retrieval of Barnes task. In experiment 1, rats received 15 daily i.c.v. infusions of saline or Aβ (30, 100 or 300 pmol) plus bilateral CA1 infusions
in the first day, and were exposed to 3 sequences of Barnes task (training, 24h test and
10-day retest in each sequence). Sequence I was held before surgery (all the animals
learned the task), II started at 11th infusion and III started 10 days after II. The behavior
of the Aβ-treated animals varied greatly at sequences II and III, and hence no differences
were observed. There was high mortality due to treatment. At the end of the behavioral
sessions, saline and Aβ 30pmol groups were euthanized for Aβ immunohistochemistry.
The analysis by relative optical density showed increased Aβ staining in the hippocampus
and neocortex. In experiment 2 we investigated the effects of Aβ (30 pmol) infusion on
the search strategies in the Barnes maze. Animals went through one sequence of Barnes
task (4 trainings with 2 trials each and a 3-day test, in order to increase difficulty). In the
probe test, although Aβ animals showed some retrieval, they showed preference for nonspatial
strategies, opposed to saline-treated rats. We concluded that Aβ infusion induced
subtle alterations in spatial memory, compatible with the initial stages of AD, which is
relevant for investigations of potential neuroprotective approaches. In the last stage,
animals submitted to the same infusion protocol described above were concomitantly
treated orally with 200 mg/kg of E. velutina (mulungu) extract and went through 2 Barnes
task sequences. In general, no differences were observed among the groups in acquisition
or retrieval. Thus, we concluded that the protocol used here was not able to detect a
beneficial effect of mulungu extract in the Aβ infusion AD model.
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Fictions of the self : studies in female modernism : Jean Rhys, Gertrude Stein and Djuna BarnesGroves, Robyn January 1987 (has links)
This thesis considers elements of autobiography and autobiographical fiction in the writings of three female Modernists: Jean Rhys, Gertrude Stein and Djuna Barnes. In chapter 1, after drawing distinctions between male and female autobiographical writing, I discuss key male autobiographical fictions of the Modernist period by D.H. Lawrence, Marcel Proust and James Joyce, and their debt to the nineteenth century literary forms of the Bildungsroman and the Künstlerroman. I relate these texts to key European writers, Andre Gide and Colette, and to works by women based on two separate female Modernist aesthetics: first, the school of "lyrical transcendence"—Dorothy Richardson, Katherine Mansfield and Virginia Woolf—in whose works the self as literary subject dissolves into a renunciatory "female impressionism;" the second group—Rhys, Stein and Barnes--who as late-modernists, offer radically "objectified" self-portraits in fiction which act as critiques and revisions of both male and female Modernist fiction of earlier decades.
In chapter 2, I discuss Jean Rhys' objectification of female self-consciousness through her analysis of alienation in two different settings: the Caribbean and the cities of Europe. As an outsider in both situations, Rhys presents an unorthodox counter-vision. In her fictions of the 1930's, she deliberately revises earlier Modernist representations, by both male and female writers, of female self-consciousness. In the process, she offers a simultaneous critique of both social and literary conventions.
In chapter 3, I consider Gertrude Stein's career-long experiments with the rendering of consciousness in a variety of literary forms, noting her growing concern throughout the 1920's and 1930's with the role of autobiography in writing. In a close reading of The Autobiography of Alice B. Toklas, I examine Stein's parody and "deconstruction" of the autobiographical form and the Modernist conception of the self based on memory, association and desire. Her witty attack on the conventions of narrative produces a new kind of fictional self-portraiture, drawing heavily on the visual arts to create new prose forms as well as to dismantle old ones.
Chapter 4 focuses on Djuna Barnes' metaphorical representations of the self in prose fiction, which re-interpret the Modernist notion of the self, by means of an androgynous fictional poetics. In her American and European fictions she extends the notion of the work of art as a formal, self-referential and self-contained "world" by subverting it with the use of a late-modern, "high camp" imagery to create new types of narrative structure.
These women's major works, appearing in the 1930's, mark a second wave of Modernism, which revises and in certain ways subverts the first. Hence, these are studies in "late Modernism" and in my conclusion I will consider the distinguishing features of this transitional period, the 1930's, and the questions it provokes about the idea of periodization in general. / Arts, Faculty of / English, Department of / Graduate
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A neural mechanism of observational learning in rats using Barnes maze / バーンズ迷路を用いたラットの他個体観察学習の神経メカニズム / バーンズ メイロ オ モチイタ ラット ノ タコタイ カンサツ ガクシュウ ノ シンケイ メカニズム山田 基樹, Motoki Yamada 22 March 2021 (has links)
博士(理学) / Doctor of Philosophy in Science / 同志社大学 / Doshisha University
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Form in the Organ Symphonies of Edward Shippen Barnes (1887-1958)Richardson, Collin A. 09 June 2015 (has links)
No description available.
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70 |
The Induction of Traumatic Brain Injury by Blood Brain Barrier DisruptionSkopin, Mark D. 10 June 2011 (has links)
No description available.
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