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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.
81

DANCING AMBIVALENCE: A CRITICAL ANALYSIS OF MARK MORRIS' CHOREOGRAPHY IN DIDO AND AENEAS (1989), THE HARD NUT (1991), AND ROMEO AND JULIET, ON MOTIFS OF SHAKESPEARE (2008).

Jae, Hwan Jung January 2012 (has links)
Mark Morris is deeply engaged with dance traditions and the classics, but he transforms them into modern, eclectic pieces. He often dissolves the distinctions between reality and fantasy, and good and evil, emphasizing reconciliation and love. Morris sculpts his own story and characters from musical elements within the overarching musical structure, portraying the characters and their emotions through detailed variations of movement quality. Characterizing Morris' dual attitudes as ambivalence, this study aims to highlight the dynamic structure and complexity of meaning in his works. I suggest that Morris' ambivalence is related to his perspective, the way he sees the world. / Dance
82

Effets du sommeil et de la privation de sommeil sur le protéome hippocampique de rat après apprentissage topographique

Poirrier, Jean-Etienne 24 March 2010 (has links)
Une des hypothèses concernant la fonction du sommeil suggère que ce dernier permettrait la plasticité neuronale et l'organisation (ou la réorganisation) synaptique, phénomènes sous-tendant des fonctions cognitives. Des perturbations spécifiques du sommeil faisant suite à un apprentissage ont en effet montré une diminution significative des performances aux niveaux des gènes et du comportement. Notre travail à visé à étudier les conséquences d'une privation de sommeil faisant suite à un apprentissage d'une tâche mnésique au niveau de l'abondance de protéines dans l'hippocampe de rat. Pour ce faire, une première étude protéomique de l'hippocampe de rat en l'absence d'apprentissage spatial spécifique a d'abord été réalisée ; elle montre l'absence de différence quantitative d'abondance protéique entre les hippocampes gauche et droit. Ensuite, une seconde étude protéomique montre qu'une privation de courte durée affecte différents réseaux de protéines, principalement liés au métabolisme cellulaire, aux voies biochimiques de l'énergie, des transports, du trafic vésiculaire, du cytosquelette et du traitement des protéines dans l'hippocampe de rat. Finalement, une troisième étude protéomique montre les effets d'un apprentissage d'une tâche spatiale en début de période d'activité diurne sur le protéome d'hippocampe de rat. Les principales protéines affectées ont ici des fonctions liées au métabolisme cellulaire et au cytosquelette.
83

Tobak på 2000-talet : Marknadsföring och uppfattning av Philip Morris / Tobacco in the 21:st century : The marketing and perception of Philip Morris

Elmsäter Aronson, Tobias, Örwén, Stina January 2014 (has links)
I denna uppsats har vi gjort en studie där syftet är att undersöka hur tobaksföretaget Philip Morris använder marknadskommunikationen i sin kommunikation av varumärket Marlboro och deras produkter. Denna uppsats är uppbyggd på tre frågeställningar: Hur marknadskommunicerar Philip Morris sitt varumärke och produkter? Vilka aspekter är det konsumenterna tänker på när de ska köpa cigaretter? Upplever konsumenterna någon påverkan från tobaksföretagens marknadskommunikation? I vår studie har vi valt att en kvantitativ studie som genomfördes i form av en enkätstudie och den besvarades endast av rökare. Respondenterna som besvarade vår enkät hittade vi i sociala medier, i tobaksforum på internet och genom att ta kontakt med personer som precis hade köpt cigaretter på ICA Luthagen i Uppsala.Huvudresultaten i uppsatsen är att Philip Morris har trots restriktiva lagar- och förordningar hittat nya sätt att vistas bland potentiella och redan existerande kunder. De flesta började röka för att det var socialt. Smaken, rutinen och varumärket var de tre viktigaste aspekterna när respondenterna köpte cigaretter. Av de 113 respondenterna så rökte 73 av dem Camel, Lucky Strike eller Marlboro. Trots detta så upplevde majoriteten av respondenterna ingen påverkan av tobaksföretagens marknadsföring/kommunikation. Vi har även kommit till slutsatsen att det är rökarna som är de största reklampelarna för tobaksföretagen. De som dag in och dag ut röker cigaretter på allmänna platser. Vi har även kunnat visa på ett glapp i upplevelsen angående frågan ”Upplever du någon påverkan från tobaksföretagens marknadsföring?” och de preferenser rökare har. De flesta av respondenterna svarade att de rökte Camel, Lucky Strike eller Marlboro och att de ansåg att varumärket spelade stor roll i köpet. Trots detta upplevde majoriteten av respondenterna ingen påverkan av tobaksföretagens marknadsföring. / Title: Tobacco in the 21st century – the marketing and perception of Philip Morris Author: Tobias Aronson & Stina Örwén Tutor: Anne-Marie Morhed Purpose: The purpose of this thesis was to study Philip Morris marketing, the perception of the brand and the reason why smokers buy certain cigarettes. How they market their brands in the 21st century. The key questions we are aiming to resolve in this essay is how Philip Morris market their own brand and their products, what aspects do consumers think about when they purchase cigarettes, and if the consumers experience the influence from the tobacco companies marketing. Method/Material: The material being used in this study was a survey that consisted of 113 people who purchased cigarettes at different grocery stores in Uppsala and an online-survey that only people whom smokes filled out. This survey consisted of 113 respondents. Main results: The main results that are demonstrated in our study is that the majority of people started smoking because it was social. The taste, routine and brand were the three most important aspects when purchasing cigarettes. Out of the 113 respondents from the survey, 73 of them smoked Camel, Lucky Strike or Marlboro which in conclusion proves that the brand plays an important role when purchasing cigarettes. We have also come to the conclusion that it is the smokers themselves that are the main source for marketing of cigarettes. The most interesting conclusion is the gap between smokers who think the brand plays an important role in the choice of cigarettes and their own attitude towards the tobacco companies. Our study demonstrates that the respondents believes that the brand is important in the choice of cigarettes but they do not experience any influence from the tobacco companies. Another result is the on about the paradox of Philip Morris will to grow as a company and the engaging in anti-smoking campaigns is a way of marketing and branding their own brand. Number of pages: 61 Course: Media and Communication studies C University: Division of Media and Communication, Department of Information Science, Uppsala University Period: Fall 2013 Keywords: Philip Morris, Tobacco, branding, corporate social performance, viral communication.
84

Relational graph models and Morris's observability : resource-sensitive semantic investigations on the untyped λ-calculus / Modèles de Graphe Relationnels et Observabilité à la Morris : recherches sémantiques sensibles aux ressources sur le λ-calcul non typé

Ruoppolo, Domenico 13 December 2016 (has links)
La thèse contribue à l’étude du λ-calcul non-typé de Church, un système de réécriture dont la règle principale est la β-réduction (formalisant l’exécution d’un programme). Nous nous concentrons sur la sémantique dénotationnelle, l’étude de modèles du λ-calcul interprétant de la même façon les λ-termes β-convertibles. On examine la sémantique relationnelle, une sémantique sensible aux ressources qui interprète les λ-termes comme des relations avec les entrées regroupées en multi-ensembles. Nous définissons une classe de modèles relationnels, les modèles de graphe relationnels (rgm’s), que nous étudions avec une approche issue de la théorie des types et de la démonstration, par le biais de certains systèmes de types avec intersection non-idémpotente. D’abord, nous découvrons la plus petite et la plus grande λ–théorie (théorie équationnelle étendant la β-conversion) représentées dans la classe. Ensuite, nous utilisons les rgm’s afin de résoudre le problème de l’adéquation complète pour la λ–théorie observationnelle de Morris, à savoir l’équivalence contextuelle de programmes que l’on obtient lorsqu’on prend les β-formes normales comme sorties observables. On résoudre le problème de différentes façons. En caractérisant la β-normalisabilité avec les types, nous découvrons une infinité de rgm’s complètement adéquats, que nous appelons uniformément sans fond. Puis, nous résolvons le problème de façon exhaustive, en prouvant qu’un rgm est complètement adéquat pour l’observabilité de Morris si et seulement si il est extensionnel (il modèle l’ŋ-conversion) et λ-König. Moralement un rgm est λ-König si tout arbre récursif infini a une branche infinie témoignée par un type non-bien-fondé / This thesis is a contribution to the study of Church’s untyped λ-calculus, a term rewritingsystem having the β-reduction (the formal counterpart of the idea of execution of programs) asmain rule. The focus is on denotational semantics, namely the investigation of mathematical models of the λ-calculus giving the same denotation to β-convertible λ-terms. We investigate relational semantics, a resource-sensitive semantics interpreting λ-terms as relations,with their inputs grouped together in multisets. We define a large class of relational models,called relational graph models (rgm’s), and we study them in a type/proof-theoretical way, using some non-idempotent intersection type systems. Firstly, we find the minimal and maximal λ-theories (equational theories extending -conversion) represented by the class.Then we use rgm’s to solve the full abstraction problem for Morris’s observational λ-theory,the contextual equivalence of programs that one gets by taking the β-normal forms asobservable outputs. We solve the problem in different ways. Through a type-theoretical characterization of β-normalizability, we find infinitely many fully abstract rgm’s, that wecall uniformly bottomless.We then give an exhaustive answer to the problem, by showing thatan rgm is fully abstract for Morris’s observability if and only if it is extensional (a model of ŋ-conversion) and λ-König. Intuitively an rgm is λ-König when every infinite computable tree has an infinite branch witnessed by some type of the model, where the witnessing is a property of non-well-foundedness on the type.
85

[en] ROBERT MORRIS IN DANCE STATE / [pt] ROBERT MORRIS EM ESTADO DE DANÇA

PATRICIA LEAL AZEVEDO CORREA 03 April 2008 (has links)
[pt] O artista norte-americano Robert Morris é conhecido sobretudo como escultor, mas sua obra abrange uma diversidade de meios, procedimentos e materiais, dentre os quais a dança. Morris esteve diretamente envolvido com grupos de dança entre o final da década de 1950 e meados da década de 1960, período em que participou do que foram talvez os dois mais importantes focos de pesquisa em dança, nos Estados Unidos, para a sua geração: as atividades que se desenvolveram em São Francisco, ao redor da professora e dançarina Ann Halprin, e as atividades que, em Nova York, resultaram da formação do grupo Judson Dance Theater. Nesse período, além de atuar como dançarino em trabalhos de outros artistas, Morris criou um pequeno mas significativo conjunto de trabalhos de dança. A tese toma esse conjunto como base para um estudo da obra do artista e procura vê- la, em grande parte, como desdobramento de experiências e questões surgidas no âmbito da dança, em diálogo com o seu concomitante envolvimento na pintura, no desenho e na escultura. Discutindo alguns dos pontos principais desse diálogo - como o reducionismo minimalista, os procedimentos de tarefa e instruções, a ênfase na temporalidade e na literalidade da ação corporal - e alguns de seus conceitos centrais - como estado de dança, forma vazia e anti-forma - , a tese se propõe a ampliar as possibilidades de análise e compreensão de um momento crucial não só para a formação e o curso subseqüente da obra de Morris, mas também para a constituição do campo ampliado da arte contemporânea. / [en] The North American artist Robert Morris is known mostly as a sculptor, but his work encloses a diversity of means, procedures and materials among which dance. Morris was directly involved with dance groups between the end of the decade of 1950 until mid 1960, period in which he participated in what were maybe the two most important focuses of research in dance, in the United States, for his generation: the activities that were developed in San Francisco related to the professor and dancer Ann Halprin, and activities in New York City resulting from the formation of the group Judson Dance Theater. In this period, aside of acting as dancer in works from other artists, Morris created a small but significant set of dance works. The thesis considers this set as the basis for the study of the artist work and strives to see it, mainly, as a deployment of the experiences and questions arisen in the scope of dance, in dialogue with his concomitant involvement in painting, drawing and sculpture. Discussing some of the main points in this dialogue - as the minimalist reductionism, the procedures of tasks and instructions, the emphasis in the temporality and in the literality of the corporal action - and some of its central concepts - such as dance state, blank form and anti form - the thesis intends to extend the possibilities of analysis and comprehension of a crucial moment not only for the formation and the subsequent course of Morris work but also for the constitution of the expanded field of contemporary art.
86

Influência do exercício materno espontâneo e da anóxia neonatal no desenvolvimento, na memória espacial e no hipocampo de ratos. / Influence of spontaneous maternal exercise and neonatal anoxia in the development, spatial memory and in the hippocampus of rats.

Lee, Vitor Yonamine 16 March 2015 (has links)
A anóxia neonatal decorre da redução de oxigênio no feto ou no recém-nascido e provoca morte e morbidade principalmente nos prematuros. Neste projeto avaliamos se o exercício físico espontâneo em ratas gestantes atenua os problemas no desenvolvimento e na cognição provocados pela anóxia neonatal nos filhotes. Para tanto, avaliamos o desenvolvimento somático e sensorimotor dos filhotes até o desmame e na idade adulta avaliamos a sua memória espacial. Também analisamos a densidade de neurônios e a expressão relativa de sinapsina I no hipocampo de animais jovens e adultos. O exercício materno espontâneo foi capaz de reverter o atraso provocado pela anóxia neonatal no aparecimento de características físicas e reflexos. Em animais jovens, ele também diminuiu a redução, pela anóxia, da densidade neuronal no giro dentado e da expressão relativa de sinapsina I. Os efeitos do exercício materno e da anóxia neonatal aparentemente não persistiram até a vida adulta. Assim, o exercício materno espontâneo atenua os efeitos da anóxia neonatal em jovens. / Neonatal anoxia follows from oxygen reduction in fetus or newborn and causes death and morbidity mainly in premature children. We evaluated if spontaneous maternal exercise in pregnant rats attenuates problems in the development and in the cognition caused by neonatal anoxia in pups. Thereunto, we evaluated the somatic and sensory-motor development of pups until weaning and, at adult age, we evaluated their spatial memory. We also analysed the neuron density and the relative expression of synapsin I in the hippocampus of young and adult animals. The spontaneous maternal exercise was able to reverse the delay caused by neonatal anoxia in the development of physical traits and reflexes. In young animals, maternal exercise also decrease the reduction, by anoxia, of neuronal density in the dentate gyrus and of relative expression. of synapsin I. Maternal exercise and neonatal anoxia effects apparently did not persist until adulthood. Thus, spontaneous maternal exercise attenuates neonatal anoxia effects in Young rats.
87

Going into labor : production and reproduction in fin de siècle British literature /

Shea, Daniel Patrick, January 2006 (has links)
Thesis (Ph. D.)--University of Oregon, 2006. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 280-290). Also available for download via the World Wide Web; free to University of Oregon users.
88

Efeitos da exposição à nicotina e/ou ao etanol durante a adolescência: alterações glutamatérgicas e na memória visuoespacial de camundongos / Effect of nicotine and/or etanol exposure during adolescence: glutamatergic and visuospatial memory alterations in mice

Ana Heloisa de Medeiros 10 April 2012 (has links)
Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / Adolescentes humanos frequentemente associam o fumo do tabaco ao consumo de bebidas alcoólicas. A despeito desta associação, pouco se sabe sobre a neurobiologia básica da coexposição no cérebro adolescente. No presente estudo, avaliamos os efeitos da exposição, que ocorreu do 30 ao 45 dia de vida pós natal (PN30 a PN45), à nicotina e/ou ao etanol durante a adolescência (PN38-45) e da retirada (PN50-57) na memória visuoespacial através do Labirinto Aquático de Morris (LAM: 6 sessões + 1 prova, 3 tentativas/sessão, latência = 2 min), em 4 grupos de camundongos Suíços machos e fêmeas: (1) exposição concomitante à NIC [solução de nicotina free base (50 μg/ml) em sacarina a 2% para beber] e ETOH [solução de etanol (25%, 2 g/kg) injetada i.p. em dias alternados]; (2) exposição à NIC; (3) exposição ao ETOH; (4) veículo (VEH). Uma vez que os resultados comportamentais podem sofrer a interferência de alterações motoras, avaliamos (a) a atividade locomotora no Teste de Campo Aberto (sessão única, 5 min) e (b) a coordenação e o equilíbrio no Teste de Locomoção Forçada sobre Cilindro Giratório (5 tentativas, latência = 2 min). Para os efeitos da exposição à NIC e/ou ao ETOH na eficiência do transporte de aminoácidos excitatórios, avaliamos a captação de [3H] D-aspartato no hipocampo. A expressão do transportador glial GLAST/EAAT1 foi avaliada por Western-blot. Durante a exposição, animais ETOH e NIC+ETOH apresentaram déficits de memória nas sessões de teste e de prova no LAM enquanto, na retirada, os grupos NIC e NIC+ETOH apresentaram prejuízos na retenção. Não houve diferenças significativas entre os grupos de tratamento em nenhum dos parâmetros testados em ambos os testes motores, tanto na exposição quanto na abstinência. Os grupos NIC, ETOH e NIC+ETOH tiveram uma diminuição significativa na captação de [3H] D-aspartato ao final do período de exposição, com uma normalização da atividade dos EAATs na retirada das drogas. O tratamento com NIC e ETOH reduziu ainda a expressão de GLAST/EAAT1 no hipocampo em ambas as idades testadas. O uso de etanol na adolescência causa prejuízos à memória de camundongos, com um efeito negativo mais acentuado quando associado à nicotina. Contudo, a retirada da nicotina apresentou um efeito mandatório nos danos encontrados. Ambas as drogas, isoladamente ou na coexposição, alteram os níveis de atividade e expressão dos EAATs, sugerindo que os resultados bioquímicos estejam implicados nas alterações comportamentais encontradas. / Human adolescents frequently associate tobacco smoke and alcoholic drinks. Despite this association, little is known about the basic neurobiology of co-exposure in the adolescent brain. In the present study, we assessed the effects of nicotine and/or ethanol exposure (postnatal days 30 to 45: PN30-45) during adolescence (PN38-45) and withdrawal (PN50-57) on visuospacial memory through the Morris Water Maze (MWM: 6 sessions + 1 probe, 3 trials/session, latency = 2 min), in four groups of male and female Swiss mice: (1) Concomitant NIC [nicotine free base solution (50g/ml) in 2% saccharin to drink] and ETOH [ethanol solution (25%, 2g/kg) i.p. injected every other day] exposure; (2) NIC exposure; (3) ETOH exposure; (4) Vehicle (VEH). Once behavioral results can be affected by motor disorders, we assessed (a) locomotor activity through the Open field Test (one session, 5 min) and (b) coordination and balance through the ROTAROD Test (5 trials, latency = 2 min). To investigate the effects of NIC and/or ETOH exposure on the efficiency on excitatory amino acid transport, we assessed the [3H] D-aspartate uptake in mice hippocampus. The GLAST/EAAT1, a glial transporter, was assessed by Western-blot technique. During exposure, ETOH and NIC+ETOH animals showed deficits on memory through the session and probe trial in WMW while, during withdrawal, NIC and NIC+ETOH groups showed impairments on retention. There were no significant differences between the experimental groups in any parameters assessed in both motor tests, either during exposure and withdrawal. There was a significant decrease in the [3H] D-aspartate for NIC, ETOH and NIC+ETOH groups in the end of exposure, turning to the normal levels of EAATs activity during withdrawal. The NIC and ETOH treatment decreased the GLAST/EAAT1 expression on hippocampus in all ages tested. Ethanol use leads to memory impairments in adolescent mice, with more preeminent effects when associated to nicotine. However, the nicotine withdrawal showed a mandatory effect on memory impairments. Both drugs, singly or in co-exposure, alter activity and expression of EAATs, which suggests that biochemical results may be associated to the behavioral alterations.
89

Développement d'un AFM virtuel pour l'évaluation du bilan d'incertitude de l'AFM métrologique du LNE / Development of a Virtuel AFM to evaluate the uncertainty budget of the LNE's metrological AFM

Ceria, Paul 05 July 2017 (has links)
À l'heure où les nanotechnologies sont en plein essor, la précision des mesures réalisées à l'échelle nanométrique devient un défi essentiel pour améliorer les performances et la qualité des produits intégrant des nano. Pour répondre aux besoins sous-jacents en nanométrologie dimensionnelle, le Laboratoire National de métrologie et d'Essais (LNE) a conçu intégralement un Microscope à Force Atomique métrologique (mAFM). Son objectif principal est d'assurer la traçabilité au mètre défini par le Système International d'unités (SI) pour les mesures à l'échelle nanométrique. Pour cela, le mAFM utilise quatre interféromètres différentiels qui mesurent en temps réel le déplacement relatif de la pointe par rapport à l'échantillon. Cet instrument de référence est destiné à l'étalonnage d'étalons de transfert couramment utilisés en microscopie à champ proche (SPM) et en microscopie électronique à balayage (SEM). Lors de ce processus, une incertitude de mesure est évaluée. Elle détermine un niveau de confiance de l'étalonnage réalisé par le mAFM. Cette incertitude est généralement évaluée grâce à des mesures expérimentales permettant de déterminer l'impact de certaines sources d'erreur qui dégradent les mesures à l'échelle du nanomètre. Pour d'autres sources d'erreur, leur évaluation reste complexe ou expérimentalement impossible. Pour surmonter cette difficulté, le travail de thèse a consisté à mettre en place un modèle numérique de l'instrument nommé " AFM virtuel ". Il permet de prévoir l'incertitude de mesure du mAFM du LNE en ciblant les sources critiques d'erreur grâce à l'utilisation d'outils statistiques tels que la Méthode de Monte Carlo (MCM), les plans de Morris et les indices de Sobol. Le modèle utilise essentiellement la programmation orientée objet afin de prendre en compte un maximum d'interactions parmi les 140 paramètres d'entrée, en intégrant des sources jusqu'ici négligées ou surestimées par manque d'informations. / At present where nanotechnology applications are growing fast and nano products spreading worldwide, measurement accuracy at nanometer scale becomes an essential challenge to improve the performance and the quality of products integrating nano. To meet the specific needs in the field of dimensional nanometrology, LNE (French metrology institute) integrally designed a metrological Atomic Force Microscope (mAFM). Its main objective is to ensure the traceability of nanoscale measurements to the meter as defined by the International System of Units (SI). The mAFM uses four differential interferometers which measure the tip to sample relative position. This instrument will be devoted to the calibration of transfer standards commonly used in scanning probe microscopy (SPM) and scanning electron microscopy (SEM). During this process, a measurement uncertainty is evaluated to determine a confidence level of the calibration realized by the mAFM. This uncertainty is usually evaluated thanks to experimental measurements which determine the impact of some error sources which degrade measurements at the nanoscale. For other components, their evaluation can be more complex and sometimes impossible to estimate experimentally. To overcome this difficulty, the thesis work consisted in the development of a numerical model called "Virtual AFM". It allows producting the measurement uncertainty of the LNE's mAFM and to identify the critical components by using statistic tools such as Monte Carlo Method (MCM), Morris' design and Sobol' indices. The model uses essentially oriented-object programming to take into account a maximum of interactions from about 140 input quantities. It allowed integrating components previously neglected or overestimated due to a lack of information.
90

Efeitos da exposição à nicotina e/ou ao etanol durante a adolescência: alterações glutamatérgicas e na memória visuoespacial de camundongos / Effect of nicotine and/or etanol exposure during adolescence: glutamatergic and visuospatial memory alterations in mice

Ana Heloisa de Medeiros 10 April 2012 (has links)
Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / Adolescentes humanos frequentemente associam o fumo do tabaco ao consumo de bebidas alcoólicas. A despeito desta associação, pouco se sabe sobre a neurobiologia básica da coexposição no cérebro adolescente. No presente estudo, avaliamos os efeitos da exposição, que ocorreu do 30 ao 45 dia de vida pós natal (PN30 a PN45), à nicotina e/ou ao etanol durante a adolescência (PN38-45) e da retirada (PN50-57) na memória visuoespacial através do Labirinto Aquático de Morris (LAM: 6 sessões + 1 prova, 3 tentativas/sessão, latência = 2 min), em 4 grupos de camundongos Suíços machos e fêmeas: (1) exposição concomitante à NIC [solução de nicotina free base (50 μg/ml) em sacarina a 2% para beber] e ETOH [solução de etanol (25%, 2 g/kg) injetada i.p. em dias alternados]; (2) exposição à NIC; (3) exposição ao ETOH; (4) veículo (VEH). Uma vez que os resultados comportamentais podem sofrer a interferência de alterações motoras, avaliamos (a) a atividade locomotora no Teste de Campo Aberto (sessão única, 5 min) e (b) a coordenação e o equilíbrio no Teste de Locomoção Forçada sobre Cilindro Giratório (5 tentativas, latência = 2 min). Para os efeitos da exposição à NIC e/ou ao ETOH na eficiência do transporte de aminoácidos excitatórios, avaliamos a captação de [3H] D-aspartato no hipocampo. A expressão do transportador glial GLAST/EAAT1 foi avaliada por Western-blot. Durante a exposição, animais ETOH e NIC+ETOH apresentaram déficits de memória nas sessões de teste e de prova no LAM enquanto, na retirada, os grupos NIC e NIC+ETOH apresentaram prejuízos na retenção. Não houve diferenças significativas entre os grupos de tratamento em nenhum dos parâmetros testados em ambos os testes motores, tanto na exposição quanto na abstinência. Os grupos NIC, ETOH e NIC+ETOH tiveram uma diminuição significativa na captação de [3H] D-aspartato ao final do período de exposição, com uma normalização da atividade dos EAATs na retirada das drogas. O tratamento com NIC e ETOH reduziu ainda a expressão de GLAST/EAAT1 no hipocampo em ambas as idades testadas. O uso de etanol na adolescência causa prejuízos à memória de camundongos, com um efeito negativo mais acentuado quando associado à nicotina. Contudo, a retirada da nicotina apresentou um efeito mandatório nos danos encontrados. Ambas as drogas, isoladamente ou na coexposição, alteram os níveis de atividade e expressão dos EAATs, sugerindo que os resultados bioquímicos estejam implicados nas alterações comportamentais encontradas. / Human adolescents frequently associate tobacco smoke and alcoholic drinks. Despite this association, little is known about the basic neurobiology of co-exposure in the adolescent brain. In the present study, we assessed the effects of nicotine and/or ethanol exposure (postnatal days 30 to 45: PN30-45) during adolescence (PN38-45) and withdrawal (PN50-57) on visuospacial memory through the Morris Water Maze (MWM: 6 sessions + 1 probe, 3 trials/session, latency = 2 min), in four groups of male and female Swiss mice: (1) Concomitant NIC [nicotine free base solution (50g/ml) in 2% saccharin to drink] and ETOH [ethanol solution (25%, 2g/kg) i.p. injected every other day] exposure; (2) NIC exposure; (3) ETOH exposure; (4) Vehicle (VEH). Once behavioral results can be affected by motor disorders, we assessed (a) locomotor activity through the Open field Test (one session, 5 min) and (b) coordination and balance through the ROTAROD Test (5 trials, latency = 2 min). To investigate the effects of NIC and/or ETOH exposure on the efficiency on excitatory amino acid transport, we assessed the [3H] D-aspartate uptake in mice hippocampus. The GLAST/EAAT1, a glial transporter, was assessed by Western-blot technique. During exposure, ETOH and NIC+ETOH animals showed deficits on memory through the session and probe trial in WMW while, during withdrawal, NIC and NIC+ETOH groups showed impairments on retention. There were no significant differences between the experimental groups in any parameters assessed in both motor tests, either during exposure and withdrawal. There was a significant decrease in the [3H] D-aspartate for NIC, ETOH and NIC+ETOH groups in the end of exposure, turning to the normal levels of EAATs activity during withdrawal. The NIC and ETOH treatment decreased the GLAST/EAAT1 expression on hippocampus in all ages tested. Ethanol use leads to memory impairments in adolescent mice, with more preeminent effects when associated to nicotine. However, the nicotine withdrawal showed a mandatory effect on memory impairments. Both drugs, singly or in co-exposure, alter activity and expression of EAATs, which suggests that biochemical results may be associated to the behavioral alterations.

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