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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.
251

Liberalidade e gratuidade no âmbito da doação / Liberality and gratuity in the context of gift

Sergio Tuthill Stanicia 19 April 2016 (has links)
O objeto deste trabalho será analisar criticamente a maneira como o direito conceitua a doação. Será dividido em três partes. O Capítulo I tratará dos diversos modos como a doação foi estruturada no direito romano, no direito francês, no direito italiano e no direito brasileiro, das razões para essa diversidade e possíveis críticas à estruturação atual. O Capítulo II cuidará dos critérios para delimitar a fattispecie da doação e distingui-la dos demais contratos gratuitos. Normalmente, a doutrina identifica um elemento objetivo e um elemento subjetivo como caracterizadores da doação. O Capítulo III problematizará esses elementos, a fim de indagar sobre a abrangência do conceito jurídico de doação, tendo como base dois aspectos: a possibilidade de a doação ter por objeto prestações de fazer e o papel atribuído ao chamado animus donandi. / The purpose of this thesis is to analize critically the legal concept of gift. It will be divided into three parts. Chapter I covers the different legal structuring of gifts in Roman Law, French Law, Italian Law and Brazilian Law. The chapter also covers the reasons for the existence of different concepts and possibile criticism of the actual structure of gifts. Chapter II deals with the criteria for defining a legal concept of gift and the distinction between gifts and other gratuitous contracts. Generally, legal science identifies an objective element and a subjective element as characteristic features of gifts. Chapter III discusses these elements focused on the magnitude of the legal concept of gift in accordance with two aspects: the possibility of gratuitous services to be considered gifts and the role assigned to the so-called animus donandi.
252

Efeito do enriquecimento ambiental perinatal de f?meas em comportamentos relacionados a ansiedade na sua prole / Perinatal environmental enrichment effects in anxiety like behaviors in females offspring

JOBIM, Camila Mendon?a Netto 25 May 2016 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-05-03T18:25:52Z No. of bitstreams: 1 2016 - Camila Mendon?a Netto Jobim.pdf: 2312664 bytes, checksum: b9e51b7bf56f9bfc3fabc284e20448e8 (MD5) / Made available in DSpace on 2017-05-03T18:25:52Z (GMT). No. of bitstreams: 1 2016 - Camila Mendon?a Netto Jobim.pdf: 2312664 bytes, checksum: b9e51b7bf56f9bfc3fabc284e20448e8 (MD5) Previous issue date: 2016-05-25 / Anxiety is one of the most common psychiatric disorder in society. This disorders may occur as a result of an individual?s inability to face a stress event (physical or emotional), which can happen in youth or adulthood. The exposure to stressors during the perinatal period can cause consequences for life. Thus environmental enrichment is used either as preventive or attenuating stressor events. The aim of this study was to evaluate the behavioural response related to anxiety on the offspring of females mice raised in an enriched environment during their perinatal period. Experimentally was created male and female groups during tree generation (F0, F1 and F2). Animals was raised in standard environment (P) and enriched environment (E) in F0. In the next generation (F1), females that was born in E was placed to P and composed the E-P group. Therefore, in F2 we had the P, E-P and E group. This group had their maternal behavior observed, submitted to behavioral models, plasmatic corticosterone assayed as well the expression of the AVP1a, AVP1b, CRH1, CRH2 and OT receptors. As results, we verify that the enriched environment only in F0 changed the maternal behavior (46,8?8,9% P; 77,8?5,4% E; p=0,0138). The anxiolytic effect was noted in all the models applied. In elevated plus maze it was observed in E group during all the generation. Only in F2, the E group showed anxiolytic effect in open field test. On light-dark box, the E-P and E group was different of P in latency to explore the light part in F1 and F2. The last generation, F2, was tested and showed a different latency to eat the pellet in novelty suppressed feeding test. The E group had the shortest time to eat the pellet, followed by E-P and P had the biggest (147,7?15,7s; 101,4?8,8s; 62,8?9,4s; F=13,0700 p=0,0001 - male) (143,7?11,4s; 93,7?20,4s; 38,3?5,3s; F=16,1900 p<0,0001 - female). The transgeracional effect could be visualized in light-dark box and novelty suppressed feeding tests because the E-P group had their behavior similar to E even that had not been directly exposed to the enriched environment. There is no difference between sexes in results of the models. The neuroendocrine analyzes there no significate result. Then, we suggest that transgenerational effect is due to exposure of the dams to the environmental enrichment during perinatal period. / Os transtornos de ansiedade est?o entre as doen?as psiqui?tricas mais comuns na sociedade. Eles se d?o pela incapacidade do indiv?duo em lidar com um evento estressor (f?sico ou emocional), podendo acometer desde a inf?ncia at? a idade adulta. O desencadeamento da ansiedade no per?odo perinatal pode acarretar em mudan?as comportamentais ao longo da vida. Neste sentido, o enriquecimento ambiental ? utilizado tanto como atenuante dos efeitos estressores quanto como preventivo. Sendo assim, buscou-se avaliar comportamentos relacionados ? ansiedade de filhotes de f?meas expostas ao enriquecimento ambiental durante per?odo perinatal. Para isso foram criados grupos de machos e f?meas ao longo de tr?s gera??es-F0, F1 e F2. Em F0 foram montados 2 grupos, o padr?o (P) e o enriquecido (E). Em F1 f?meas que estavam em ambiente enriquecido durante o per?odo perinatal foram passadas para o ambiente padr?o formando o grupo enriquecimento-padr?o (E-P). F2 ent?o passou a ter grupos dos tr?s grupos, P, E-P e E. Estes grupos foram submetidos a observa??es do comportamento materno, modelos de ansiedade, dosagem de corticosterona plasm?tica e a avalia??o da express?o dos genes para os receptores AVP1a, AVP1b, CRH1, CRH2 e OT. Como resultados verificamos que o comportamento materno em F0 foi maior no grupo enriquecido (E) (46,8?8,9% P; 77,8?5,4% E; p=0,0138), por?m n?o em F1 (68,4?4,1% P; 71,1?6% E-P; 78,1?3,1% E; F=0,8120 p=0,4689). Foi constatado o efeito ansiol?tico nos modelos comportamentais utilizados. No labirinto em cruz elevado-LCE, este efeito pode ser notado apenas no grupo E das tr?s gera??es avaliadas. No campo aberto CA, apenas o grupo E de F2 apresentou comportamentos relacionados a ansiedade significativamente diferentes dos demais grupos. O teste da caixa claro-escuro-CCE mostrou diferen?a entre os grupos E-P e E em rela??o ao grupo P na lat?ncia para explorar o ambiente claro em F1 e F2. E o teste da supress?o da alimenta??o pela novidade-NSF indicou que os grupos s?o diferentes entre si na lat?ncia para se alimentar, o maior tempo foi de P, seguido de E-P e depois de E (147,7?15,7s; 101,4?8,8s; 62,8?9,4s; F=13,0700 p=0,0001 - Machos) (143,7?11,4s; 93,7?20,4s; 38,3?5,3s; F=16,1900 p<0,0001 - F?meas). Pode ser constado o efeito transgeracional em CCE e NSF, onde a exposi??o da m?e ao enriquecimento influenciou o comportamento dos filhotes que n?o foram diretamente expostos ao ambiente enriquecido. Todos os resultados dos modelos comportamentais valem para machos e f?meas e n?o h? diferen?as em rela??o ao g?nero. Os par?metros neuroend?crinos analisados n?o mostraram diferen?a significativa entre os grupos. Sugere-se ent?o que o efeito transgeracional se deu apenas pela exposi??o das m?es ao ambiente enriquecido no per?odo perinatal e manifestou-se comportamentalmente.
253

Uso de ferramentas como enriquecimento ambiental para macacos-prego (Cebus apella) cativos / Tool use as environmental enrichment for captives capuchin monkeys (Cebus apella)

Olívia de Mendonça-Furtado 10 October 2006 (has links)
Manter animais em cativeiro implica no dever ético de lhes proporcionar saúde física e psicológica. Procedimentos conhecidos como Enriquecimento Ambiental buscam elevar o bem-estar de animais cativos. Neste trabalho, três artefatos foram testados para avaliar sua eficácia como enriquecimento ambiental para macacos-prego (Cebus apella). Dois destes artefatos (Brinquedo e Caixa de forrageamento) já haviam sido testados anteriormente por Boinski et al. (1999). O terceiro artefato (Ferramenta) foi testado pela primeira vez e buscava proporcionar aos animais a possibilidade de executar um comportamento típico da espécie: a quebra de cocos. Usamos medidas comportamentais e de corticosterona fecal para medir os efeitos dos artefatos. Foram encontradas algumas diferenças significativas entre as condições experimentais (controles e com artefatos), e entre a freqüência de interação com os artefatos, porém os resultados não nos possibilitam afirmar se algum dos artefatos seria um enriquecimento ambiental eficaz para macacos-prego cativos. Acreditamos que experimentos ainda devem ser feitos para elucidar os efeito de fatores como: o ambiente externo ao recinto, os procedimentos de manutenção direcionados aos animais e a metodologia de aplicação dos artefatos, sobre o bem-estar de animais cativos. / Keeping animals in captivity implies in an ethical duty of offering conditions that foster their physical and psychological health. Procedures known as Environmental Enrichment seek to enhance animals’ life quality. Here we tested three stimuli efficiency as environmental enrichment for captive capuchin monkeys (Cebus apella). Two which had been previously tested (Toy and Box) by Boinski et al. (1999). The third one (Tool) was tested for the first time and aimed giving the animals the opportunity to perform a species-typical behavior: cracking open nuts. The stimuli had their effects measured by behavioral and fecal corticosterone sampling. Some statistical significant differences were found between experimental conditions (control and stimuli) and between the frequencies of interaction with the stimuli. The data, however, did not point to any of the tested stimuli as effective environmental enrichment for capuchin monkeys. We believe, therefore, that more research should be conducted in order to clarify the effects of factors such as the environment outside the cages, the maintenance procedures, and the stimulus presentation procedures, on the well-being of captive animals.
254

Behaviour of settling coral reef fishes and supplementary management tools

Heenan, Adel January 2010 (has links)
Coral reef fish larvae take an active role in selecting their settlement site and sensory cues may help them to orientate during this process. As settlement is a period of transition through which the majority of individuals do not survive, it is often a focal point for the management of coral reef populations, which are of high conservation concern. In this thesis, I used choice tests and in situ techniques to assess the response of settlement-stage larvae to a range of odour, light and acoustic cues and I found that larvae are more selective in their response to sensory stimuli than previously thought. Micro-habitat odours are not likely to be used during settlement orientation, and odour cues may be used to avoid inappropriate settlement sites. The photopositive behaviour of larval fish is likely to match their spectral sensitivity but this proved difficult to assess in situ because of the high amount of spatial and temporal variation in larval distribution. The positive response of settlement-stage fish to played back reef noise is location specific as well as being highly specific to the reef sound recording. To understand whether it might be the composition of reef sound that drives the selective response of larvae to acoustic cues, I took sound recordings while collecting visual data on fish diversity and the behavioural activity of a sound producing, or soniferous, fish species. I found that the variation in intensity of reef noise matches the activity patterns of a soniferous species, and when reef noise is most intense is when visual estimates on the diversity of the reef fish assemblage are decreased. This information provides the basis for understanding how changes in the reef soundscape may effect larval recruitment and has exciting implications for using sound recordings as a method to monitor coral reefs. Finally, I tested the viability of releasing reared larvae to boost depleted populations and found that collecting and holding settlement-stage fish for a week can increase survival, relative to natural settlement. These data demonstrate that applying our knowledge of the settlement behaviour of coral reef fish will make a significant contribution to developing tools for management.
255

Fitossociologia de ?reas enriquecidas com o palmiteiro Euterpe edulis (martius) em paisagens alteradas da Mata Atl?ntica / Phytosociology of enriched areas with the palm cabbage plantation. Euterpe edulis (Martius) in modified views from Atlantic Forest .

Pinheiro, Marco Aur?lio Soares 30 August 2008 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2018-01-25T12:42:16Z No. of bitstreams: 1 2007 - Marco Aur?lio Soares Pinheiro.pdf: 727221 bytes, checksum: 4a4a5210bea956397c8eb8b3c6ed9487 (MD5) / Made available in DSpace on 2018-01-25T12:42:16Z (GMT). No. of bitstreams: 1 2007 - Marco Aur?lio Soares Pinheiro.pdf: 727221 bytes, checksum: 4a4a5210bea956397c8eb8b3c6ed9487 (MD5) Previous issue date: 2008-08-30 / The present study was developed at Santuary of Silvester Life, Serra da Conc?rdia, Valen?a (RJ), aiming to collect informations which can subsidize the handling and the preservation of Euterpe edulis at the Atlantic Forest; to study the floristics and the structure of a secondary forest, which was submited to enrichment; to valuate the E. edulis development in a plantation of enrichment, and to confirm the viability of development of palm cabbage culture in impacted forestal remainings. Were used collecting of floristic and phytosociological facts in two parcels of 20x50m. It was estimated the viability of plantation of enrichment with E. edulis by analysing the growth in two parcels of 20x50m. It was established four classes of size of exposed stirps (C1= up to 0,5m; C2 from 0,5 to 1,5m; C3 from 1,3 to 3,0m and C4 from 3,0m on and with circumference at chest level (CAP) > 15cm). Each parcel was devided in ten subparcels of 10x10m, in which all palm cabbage plantation of (C4 class) had their CAP measurings and exposed etirps height taken.In each subparcel of 10x10m it was allocated a subparcel of 4,0x4,0m, where the individuals of the classes C1,C2 and C3 have had their measurings of diameter of colon, CAP and height of stirps taken. All palm cabbage were identified with aluminium plate printed in low relief and fixed with copper nails.The parcel 1 can be found at the bottom of the region nearby a stream, while the parcel 2 can be found almost 50m above the first parcel. It has been done two measurings in an interval of six months and, at the and of this period, it had been estimated the percentage of survival and of changing of class. The analyses of growth in each sample, and also between one another was done by the non parametric test of Kruskal-Wallis. The fragment was characterized by the index of similarity and diversity, by Margalef with some other seven remainings of Atlantic Forest with different degrees of impactation and distincts successional stages. It was also compared some abiotic characteristics between the fragments. The individuals of C1; C2 and C3 from parcel1 were significantly grown, speaking about the diameter of colon. The individuals of the same classes of parcel 2 have not had an expressive growth, but there have had a significative growth in height of exposed stirps for these classes. The C4 from parcel 1 were grown concerning to the CAP, but those one of the parcel 2 didn?t. Speaking about the height of stirps in both of the parcels, the growth was very significative. The percentage of survival were about 95,8% and 100% in the parcels 1 and 2, respectively. / O presente estudo foi desenvolvido no Santu?rio de Vida Silvestre, Serra da Conc?rdia, Valen?a (RJ), com o objetivo de coletar informa??es que possam subsidiar o manejo e a conserva??o de Euterpe edulis na Floresta Atl?ntica; estudar a flor?stica e a estrutura de uma floresta secund?ria submetida a enriquecimento; avaliar o desenvolvimento de E. edulis em plantio de enriquecimento e confirmar a viabilidade do desenvolvimento da cultura de palmito em remanescentes florestais impactados. Foram utilizados levantamentos flor?stico e fitossociol?gico em duas parcelas de 20x50m. Avaliou-se a viabilidade do plantio de enriquecimento com E. edulis atrav?s de an?lise de crescimento em duas parcelas de 20x50m. Foram estabelecidas quatro classes de tamanho de estipe exposta (C1=at? 0,5m; C2 de 0,5 a 1,5m; C3 de 1,3 a 3,0m e C4 acima de 3,0m e com circunfer?ncia a altura do peito (CAP) 15cm) Cada parcela foi dividida em dez subparcelas de 10x10m, onde todos os palmiteiros da classe C4 tiveram suas medidas de CAP e altura de estipe exposta tomadas. Em cada subparcela de 10x10m foi alocada uma subparcela de 4,0x4,0m, em que os indiv?duos das classes C1, C2 e C3 tiveram suas medidas de di?metro de colo, CAP e altura de estipe tomados. Todos os palmitos foram identificados com placas de alum?nio impressas em baixo relevo e afixadas com pregos de cobre. A parcela 1 se encontra em regi?o mais baixa, pr?xima ao c?rrego, enquanto que a parcela 2 se localiza cerca de 50m acima da primeira parcela. Foram feitas duas medi??es com intervalo de seis meses e, ao final deste per?odo, foram calculados os percentuais de sobreviv?ncia e de mudan?a de classe. A an?lise do crescimento em cada amostra, e tamb?m entre elas, foi feita atrav?s do teste n?o param?trico de Kruskal-Wallis. Caracterizou-se o fragmento atrav?s do ?ndice de similaridade e diversidade de Margalef com outros sete remanescentes de Mata Atl?ntica com diferentes graus de impacta??o e est?gios sucessionais distintos. Tamb?m foram comparadas algumas caracter?sticas abi?ticas entre os fragmentos. Os indiv?duos de C1, C2 e C3 da parcela 1 cresceram significativamente quanto ao di?metro de colo. Os indiv?duos das mesmas classes da parcela 2 n?o tiveram crescimento significativo, mas houve crescimento significativo em altura de estipe exposta para estas classes. Os C4 da parcela 1 cresceram quanto ao CAP, mas os da parcela 2, n?o. Quanto ? altura de estipe, em ambas as parcelas o crescimento foi significativo. Os percentuais de sobreviv?ncia foram de 95,8% e 100% nas parcelas 1 e 2, respectivamente.
256

L'enrichissement olfactif au cours du vieillissement : implication de la Noradrénaline et modèle de réserve cognitive / Olfactory enrichment during aging : improvement of Noradrenaline and model of cognitive reserve

Terrier, Claire 27 November 2018 (has links)
Le vieillissement est un phénomène biologique complexe et inévitable associé à un déclin progressif des fonctions cognitives, sensorielles et motrices qui affecte la qualité de vie et la santé des sujets âgés. Le vieillissement normal s'accompagne de changements structuraux et fonctionnels, conduisant au déclin cognitif. Parmi ces changements, les altérations du système noradrénergique semblent contribuer de façon significative aux déficits cognitifs. Inversement, le maintien de l'intégrité du Locus Coeruleus semble participer à la préservation des performances. Par ailleurs, une stratégie pour promouvoir le bien vieillir propose de booster la réserve cognitive associée à un haut niveau de stimulation cérébrale et à des modulations de l'activation et de la connectivité cérébrales chez l'humain. Chez les rongeurs, l'enrichissement environnemental promouvant les stimulations sensorielles, l'activité motrice et les interactions sociales, mime les conditions de mise en place de la réserve cognitive chez l'homme et a largement montré ses effets bénéfiques sur la cognition. Les objectifs de cette thèse sont premièrement, d'étudier le rôle de la NA dans le maintien de la plasticité structurale et des capacités de discrimination olfactive chez la souris âgée, puis dans un second temps de tester l'enrichissement olfactif comme modèle de construction de la réserve cognitive. Dans une première étude, nous avons utilisé le modèle d'apprentissage perceptif olfactif pour étudier la contribution de la Noradrénaline au maintien de la plasticité structurale et des performances cognitives au cours du vieillissement chez la souris. Cet apprentissage consiste en une amélioration de la discrimination entre deux odorants proches sur le plan perceptif après une exposition répétée à ces odorants. Nos résultats suggèrent que la libération de Noradrénaline dans le bulbe olfactif via une stimulation optogénétique des fibres issues du Locus Coeruleus maintient les capacités de discrimination au cours du vieillissement. Nos données révèlent aussi une forme de plasticité du réseau noradrénergique dans le bulbe olfactif âgé. Ces résultats soutiennent l'hypothèse d'une contribution importante de la Noradrénaline au bien vieillir cérébral. Dans une deuxième étude, nous avons utilisé une stratégie basée sur un enrichissement olfactif, manipulation capable de mobiliser la Noradrénaline, proposé tout au long de la vie de l'animal, dans le but de permettre le développement d'une réserve cognitive. Nos résultats montrent qu'un tel enrichissement améliore les capacités de discrimination olfactive même à un âge avancé. De façon intéressante, les performances non olfactives de mémoire spatiale et de flexibilité sont aussi améliorées. Ces résultats indiquent que les effets bénéfiques de l'enrichissement s'étendent au-delà de la sphère olfactive et incluent des bénéfices sur différentes performances cognitives sensibles à l'âge. Nous proposons donc l'enrichissement olfactif comme un modèle de la construction d'une réserve cognitive qui nous permettra par la suite d'identifier les bases cellulaires du bien vieillir et de tester la contribution de la Noradrénaline dans la construction de la réserve cognitive / Aging is an inevitable and complex biological phenomenon associated with a progressive decline of sensory, motor and cognitive functions with time, affecting life quality and health. Normal brain aging is accompanied by functional and structural changes, leading to cognitive decline. Among these changes, age-related alterations of the noradrenergic system seem to contribute significantly to cognitive deficits. Conversely, the integrity of the Locus Coeruleus seems to allow healthy cognitive aging. A potentially powerful tool to achieve successful brain aging is to boost the cognitive reserve, associated with higher level of brain stimulation and modulations in brain activation and connectivity in humans. In rodents, environmental enrichment, increasing sensory stimulations, motor activity and social interactions, mimics the conditions leading to constitution of the cognitive reserve in humans and has largely proven cognitive benefits.The goals of this thesis are, in the first place, to study the role of Noradrenaline in the maintenance of structural plasticity and olfactory discrimination abilities in aged mice, then secondly, to test the olfactory enrichment as a model of the cognitive reserve build-up.In the first study, we used the olfactory perceptual learning paradigm to investigate the contribution of Noradrenaline to the maintenance of structural plasticity and cognitive abilities during aging in mice. This learning consists in an improvement of the discrimination between perceptually close odorants after repeated exposure to these odorants. Our results suggest that the local release of Noradrenaline in the olfactory bulb, by optogenetic stimulation of Locus Coeruleus fibers allows the maintenance of discrimination abilities during aging. Our data also reveal a form of structural plasticity of the noradrenergic innervation in the aged olfactory bulb. The overall work supports a contribution of Noradrenaline to healthy brain aging.In a second study, we used a strategy based on repeated olfactory enrichment during the whole life of the animal in order to enable the cognitive reserve buildup. Such enrichment maintained olfactory discrimination performances at late ages. Interestingly, mice’s performances in spatial memory and cognitive flexibility improved too. This result indicates that the benefits of an odor-based enrichment extend beyond the olfactory sphere and include broader cognitive benefits on age-sensitive functions. We thus propose lifelong olfactory enrichment as model of the cognitive reserve build-up to further identify its cellular basis and test the contribution of Noradrenaline to cognitive reserve build-up and healthy brain aging
257

Neurogênese e plasticidade sináptica no Hipocampo de ratos submetidos à separação materna e enriquecimento ambiental / Neurogenesis and synaptic plasticity in the hippocampus of rats submitted to maternal separation and environmental enrichment

Merlo, Suélen 23 October 2014 (has links)
Eventos estressantes durante a infância promovem alterações comportamentais e encefálicas persistentes, aumentando a predisposição para transtornos psiquiátricos. A separação materna tem sido utilizada como modelo de estresse pós-natal. Animais submetidos à separação materna apresentam uma resposta exacerbada do eixo hipotálamo-hipófise-adrenal ao estresse. Ao contrário, estudos sugerem que o ambiente enriquecido, por aumentar a neurogênese no giro denteado do hipocampo, pode ter efeitos benéficos sobre doenças de distúrbio comportamental. No presente projeto questionamos se o enriquecimento ambiental interfere com as alterações plásticas promovidas pela separação materna no hipocampo de ratos jovens. Utilizamos imunofluorescência, microscopia confocal, microscopia eletrônica e qRT- PCR de amostras coletadas por microdissecção a laser. A separação materna reduziu a neurogênese hipocampal, bem como a expressão de mRNA para os genes Nr3c1, codificador de receptores glicocorticóides, e Htr1a, codificador de receptores serotoninérgicos (5TH-1A). O enriquecimento ambiental reduziu a expressão de Htr1a. Além disso, aumentou a proporção de sinapses sobre espinhos dendríticos, sugerindo maior plasticidade sináptica. O enriquecimento ambiental, nos animais previamente submetidos à separação materna, aumentou a sobrevivência celular e a expressão de Nr3c1, mas não a diferenciação neuronal hipocampal. As alterações promovidas pela separação materna parecem ser persistentes, mas podem ser parcialmente revertidas pelo enriquecimento do ambiente. / Stressful events during childhood promote persistent behavioral and brain changes, increasing the predisposition to psychiatric disorders. The maternal separation has been used as postnatal stress model. Animals subjected to maternal separation exhibit an exaggerated response of the hypothalamus-pituitary-adrenal axis to stress. Instead, studies suggest that environmental enrichment, by increasing neurogenesis in the dentate gyrus of the hippocampus, has beneficial effects on behavioral disorders. In this project, we discuss whether the environmental enrichment interferes with plastic changes promoted by maternal separation in the hippocampus of young rats. We used immunofluorescence, confocal microscopy, electron microscopy and qRT-PCR of samples collected by a laser microdissection system. The maternal separation reduced hippocampal neurogenesis, as well as the mRNA expression for the genes Nr3c1, that codify glycocorticoid receptors, and Htr1a, that codify serotonin receptors (5HT-1A). Environmental enrichment reduced the expression of Htr1a. Furthermore, increases the proportion of synapses on dendritic spines, suggesting greater synaptic plasticity. The environment enrichment of the animals subjected to maternal separation increased cell survival and the expression of Nr3c1 mRNA, but not the neuronal differentiation in the hippocampus. The changes promoted by maternal separation are persistent, however may be partially reversed by the environmental enrichment.
258

A pesquisa com bem estar animal tendo como alicerce o enriquecimento ambiental através da utilização de objeto suspenso no comportamento de leitões desmamados e seu efeito como novidade / Research on animal welfare as a foundation and environmental enrichment through the use of object suspended in the behavior of piglets and its effect as a novelty

Pinheiro, Juliana de Vazzi 18 December 2009 (has links)
Este experimento foi realizado com 137 leitões em fase pós desmame, desmamados aos 28 dias de idade que foram submetidos a 3 tratamentos relacionados ao seu comportamento baseados na utilização de um objeto, neste caso um pneu suspenso por uma corrente, com a finalidade de enriquecimento ambiental. Os tratamentos foram: positivo (o pneu ficava disponível durante todo o período experimental para os leitões), negativo (ausência de enriquecimento ambiental) e alternado (o pneu utilizado para enriquecimento ambiental era lavado diariamente). Os leitões eram filmados em sistema contínuo, durante 24 horas, num período de 6 dias, o primeiro de adaptação e os outros 5 para análise do efeito deste objeto. Na primeira análise observamos que o período entre as 10 e 11 hs da manhã e 16 as 17 hs corresponde ao horário de maior atividade de \"jogo\" dos leitões com o objeto. Apesar de estatisticamente os dados não apresentarem significância, foi observado na segunda análise que com o passar dos dias o enriquecimento ambiental vai perdendo seu efeito, dimuindo gradativamente o interesse dos leitões pelo objeto. Através da utilização dos etogramas, realizados nos períodos encontrados na primeira análise, em intervalos de 10 minutos, pode se avaliar o comportamento diário dos animais, mostrando que as baias que continham o enriquecimento ambiental obtiveram menores freqüências de comportamentos estereotipados. / This experiment was conducted with 120 pigs in the post weaning; weaned at 28 days old that were submitted to 3 treatments related to their behavior based on the use of an object, in this case a tire suspended by a chain, with the purpose of environmental enrichment . The treatments were: positive (the tire was available throughout the experimental period for the piglets), negative (absence of environmental enrichment) and alternate (the tire used for environmental enrichment was cleaned daily).The piglets were filmed as a continuous 24 hours system, during 6 days, the first day was for adjustment and the other 5 were to analyze the effect of the object. In the first day analysis we found that the period between 10 to 11 am and 4 to 5 pm showed an increased activity with the tire as a \"game\" for the piglets. Even though statistically speaking the data was not significant, it was observed in our second analysis that throughout the days the environmental enrichment will lose its effects and the piglets\' interest for the object will diminish gradually. By using the ethogram, performed during the first analysis, at intervals of 10 minutes, you can evaluate the daily behavior of the animals, showing that the bays which contained environmental enrichment had lower frequencies of stereotyped behaviors.
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Isolation of a Rhodococcus Soil Bacterium that Produces a Strong Antibacterial Compound.

Borisova, Ralitsa Bogomilova 17 December 2011 (has links)
Rhodococci are notable for their ability to degrade a variety of natural and xenobiotic compounds. Recently, interest in Rhodococcus has increased due to the discovery of a large number of genes for secondary metabolism. Only a few secondary metabolites have been characterized from the rhodococci (including 3 recently described antibiotics). Twenty-four new Rhodococcus strains were isolated from soils in East Tennessee using acetonitrile enrichment culturing and identified using 16S rRNA analysis. Forty-seven Rhodococcus strains were screened for antibiotic production using a growth inhibition assay. One strain, MTM3W5.2, had 90% similarity to the Rhodococcus opacus 16S rRNA gene sequence and produced a large zone of inhibition against R. erythropolis and a large number of closely related species. The antimicrobial compound produced by MTM3W5.2 had a large MW of 911.5452 Da and acts much like a bacteriocin but no amino acids were detected in this molecule based on TLC analysis.
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Dual work roles : the joint effect of hybrid entrepreneurs’ regulatory focus and wage work to entrepreneurial work enrichment on entrepreneurial performance

ASANTE, Eric Adom 24 July 2018 (has links)
Hybrid entrepreneurial is phenomenal but remains under-studied in the management literature. This paper investigated the joint influence of hybrid entrepreneurs’ trait regulatory focus and wage work to entrepreneurial work enrichment (WE enrichment) on their entrepreneurial engagement and the subsequent proficient, adaptive, and proactive performance in entrepreneurial work. I first interviewed 16 hybrid entrepreneurs to obtain the understanding of their reasons for being in hybrid entrepreneurship, their regulatory focus tendencies, and the resources they transfer from wage work to entrepreneurial work. To validate the measurement scales of promotion and prevention focus, I conducted a pilot study among 66 hybrid entrepreneurs. Then, I conducted a multi-source questionnaire survey among 329 hybrid entrepreneurs and their entrepreneurial partners in Ghana. The final sample included 272 completed and matched responses. I used structural equation modeling of Mplus 7.4 to test the hypothesized model. Results of the questionnaire survey provided strong support to my hypothesized model. Promotion focus and prevention focus had positive and negative relationships with these three types of entrepreneurial performance, respectively. I also found that the opposite relationships of promotion focus and prevention focus with these three types of entrepreneurial performance were mediated by entrepreneurial engagement. Furthermore, hybrid entrepreneurs work across the wage-work and entrepreneurial roles, and I found that WE enrichment played a moderating role. Specifically, WE enrichment strengthened the positive relationship between promotion focus and entrepreneurial engagement as well as the positive indirect relationships between promotion focus and the three types of entrepreneurial performance through entrepreneurial engagement. In contrast, WE enrichment weakened the negative relationship between prevention focus and entrepreneurial engagement as well as the negative indirect relationships between prevention focus and the three types of entrepreneurial performance through entrepreneurial engagement. This research sheds light on how personality traits and dual-work context affect hybrid entrepreneurs’ entrepreneurial processes and performance outcomes. Thus, I provide theoretical implications for the literature of hybrid entrepreneurial and dual work roles. Further, this research offers important practical implications for hybrid entrepreneurs and their entrepreneurial partners, as well as investors.

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