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Procedimentos para avaliação tecnológica de equipamentos médico-hospitalares : um estudo aplicado à hemodiáliseMagnago, Patrícia Flores January 2016 (has links)
A Avaliação Tecnológica em Saúde (ATS) é uma sistemática que avalia os impactos clínicos, sociais e econômicos das tecnologias em saúde e tem como finalidade auxiliar os gestores na tomada de decisão quanto ao desenvolvimento, incorporação e descontinuação destas tecnologias. Agências de ATS têm destacado a importância da existência de métodos que visem padronizar e implantar esta sistemática em diferentes contextos. Assim, o objetivo geral desta tese é propor procedimentos para apoiar a avaliação tecnológica de equipamentos médico-hospitalares, por meio de uma pesquisa construtiva (Constructive Research) aplicada à terapia de hemodiálise. Os procedimentos propostos compõem um modelo adaptado do EuroScan, modelo desenvolvido por agências Europeias e indicado como boa prática pelo Ministério da Saúde do Brasil. Também são procedimentos ajustados às necessidades de pesquisadores de centros regionais de avaliação de equipamentos médico-hospitalares. Inicialmente, foi desenvolvida uma coleta de dados sobre os problemas de desenvolvimento e incorporação das tecnologias da saúde por meio de duas fontes: uma revisão sistemática de literatura sobre oportunidades de melhorias do EuroScan no mundo e discussões com pesquisadores no país. A partir destas investigações foi proposto um modelo preliminar de ATS, aplicado para o domínio Operacional e de Inovação na hemodiálise. Finalmente a aplicação foi validada e examinada por especialistas para a geração de um modelo final. Os principais procedimentos resultantes foram: (i) validação da relevância das avaliações para novos desenvolvimentos e incorporações tecnológicas do ponto de vista de diferentes especialistas, integrando diferentes áreas do conhecimento na ATS; (ii) operação de Observatórios Tecnológicos, auxiliando na definição das tecnologias e domínios a serem avaliadas; (iii) definição de técnicas para análise dos domínios de ATS, como o uso de séries temporais e o Technology Roadmap (TRM) para previsões sobre o futuro das inovações e o uso das dimensões da usabilidade e de incidentes críticos de riscos para os aspectos operacionais; e (iv) integração das diretrizes de ATS no Brasil em um único modelo, amparando pesquisadores não relacionados a saúde na compreensão sobre ATS e no desenvolvimento ágil de novos estudos tanto para equipamentos emergentes como em uso. Já a avaliação dos domínios selecionados para a hemodiálise resultou: (i) na identificação de um crescimento médio anual de 7% dos indicadores da terapia; (ii) no diagnóstico de usabilidade de máquinas eficazes, porém com possibilidades de gerarem maior satisfação aos usuários quanto: ao espaço entre elas, a redução dos desperdícios de água e materiais, aos planos de manutenção para evitar temperaturas elevadas, a capacitação visando mais atenção e treinamento para tarefas de apoio e aos aspectos de display (realimentação de dados e visualização); e (iii) na consolidação entre profissionais sobre um futuro promissor, para os próximos 10 anos no Brasil, da assistência homecare com máquinas de hemodiálise portáteis, mais seguras e sustentáveis. / The Health Technology Assessment (HTA) is a systematic evaluation of clinical, social and economic impacts of health technologies aiming to assist managers in the decision making process related to the development, consolidation and discontinuation of these technologies. HTA agencies have been highlighting the importance of methods to standardize and apply this systematic evaluation in different contexts. Thus, the general objective of this thesis is to propose procedures to support the technology assessment of medical-hospital equipment through a constructive research applied to hemodialysis therapy. The proposed procedures compose a EuroScan adapted model, which was developed by European agencies and is recommended as a good practice by the Brazilian Ministry of Health, and also are procedures adjusted to the needs of researchers in regional centers of medical equipment assessment. Initially, a data collection on the problems of developing and incorporating health technologies was carried out using two sources: a systematic review of the literature on opportunities to improve the EuroScan around the world and discussions with Brazilian researchers. Based on these investigations, it was proposed a preliminary HTA model applied to the hemodialysis’ Operational and Innovation domain. The application of the model was reviewed and evaluated by experts to produce a final version. The main resulting procedures were: (i) to validate the importance of assessments for new technological developments and incorporations considering the point of view of different experts from diverse knowledge areas; (ii) to operate Technological Observatories, assisting to define the technologies and domains to be evaluated; (iii) to set techniques for the analysis of HTA domains such as the use of time series and the Technology Roadmap (TRM) to make predictions about the future of innovations and the use of usability dimensions and critical incidents of risks to the operational aspects; and (iv) to integrate HTA Brazilian guidelines in a single model, supporting researchers not related to health in the understanding of HTA and fast development of new studies for both emerging and in use equipment. The assessment of the domains selected for hemodialysis led to: (i) the identification of an annual growth in therapy indicators (7% in average); (ii) the usability diagnosis of efficient machines, however with the potential to generate greater user satisfaction considering: distance between machines, reduction in the waste of water and materials, maintenance plans to avoid high temperatures, training aiming more attention to supporting tasks as well as focus on display aspects (data feedback and visualization); and (iii) the consolidation among professionals of a future, for the next 10 years in Brazil, based on homecare with portable machines, safer and more sustainable.
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Efeitos da nicotina no complexo do septo medial na via septo hipocampal em camundongos anestesiados por Ketamina / Effects of nicotine in the medial septum complex on the septohippocampal pathway in Ketamine anaesthetised miceG?is, Jos? Henrique Targino Dias 24 February 2015 (has links)
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Previous issue date: 2015-02-24 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / A administra??o de nicotina em seres humanos e roedores ? pensada como
um melhorador de mem?ria e aten??o, tamb?m pelo seu efeito positivo na Doen?a
de Alzheimer. O complexo do Septo Medial / Banda Diagonal de Broca (MS/DBB) ?
um dos principais sistemas colin?rgicos ? massivamente projetado para o
hipocampo atrav?s da F?mbria-F?rnix, via esta chamada de via septo-hipocampal.
Foi demonstrado que o MS/DBB afeta diretamente o potencial de campo local (LFP)
e a organiza??o r?tmica do hipocampo, especialmente na gera??o do ritmo teta - um
LFP r?tmico intrinsecamente relacionado com a fun??o mnem?nica do hipocampo.
Experimentos in vitro deram evid?ncias de que a nicotina aplicada no MS/DBB pode
gerar um ritmo teta na rede local do MS/DBB. Assim, o presente estudo se prop?e a
elucidar a fun??o da nicotina no MS/DBB sobre a via septo-hipocampal.
Experimentos in vivo, comparando o efeito de microinfus?es no MS/DBB de solu??o
salina (n = 5) ou nicotina (n = 8) em camundongos anestesiados por
ketamina/xilazina mostraram um aumento na densidade de pot?ncia no espectro
banda de gama (35 a 55 Hz) em ambas as estruturas (teste de Wilcoxon Rank-Sum,
p = 0,038), mas sem alterar a coer?ncia entre as estruturas na mesma banda (teste
de Wilcoxon Rank-Sum, p = 0,60). Houve tamb?m uma diminui??o na densidade
pot?ncia na banda delta (1-3 Hz) ? oscila??o induzida pela ketamina. Realizamos
tamb?m experimentos in vitro sobre o efeito da nicotina na voltagem de membrana e
no potencial de a??o de neur?nios do MS/DBB. Registramos neur?nios (n=22) em
current-clamp antes e depois da presen?a de nicotina no meio extracellular; 12
neur?nios responderam ? nicotina, metade aumentou a taxa de potenciais de a??o;
outros seis diminu?ram, diferindo significativamente no limiar do potencial de a??o (-
47,3 ? 0,9 mV vs. -41 ? 1,9 mV, respectivamente, p = 0,007) e na largura do disparo
(1,6 ? 0,08 vs. 2 ms ? 0,12 ms, respectivamente, p = 0,01). Al?m disso, realizamos
outro conjunto de experimentos in vitro, relativo ? conectividade das tr?s grandes
popula??es neuronais de MS / DBB que usam a acetilcolina, GABA ou glutamato
como neurotransmissores. O registro pareado de patch-clamp mostrou que
neur?nios glutamat?rgicos e GABA?rgicos realizam contatos intra-septais capazes
de produzir correntes sin?pticas em neur?nios p?s-sin?pticos do MS/DBB. A
probabilidade da conectividade entre diferentes popula??es neuronais foi
implementada em um modelo realista que corrobora que a rede ? altamente sens?vel
? gera??o de ritmo gama. Juntamente com os dados dispon?veis, o conjunto
completo de experi?ncias corrobora que a nicotina pode atuar como potenciador
cognitivo, e um substrato eletrofisiol?gico prov?vel ? atrav?s da indu??o de oscila??o
gama no circuito local do MS/DBB. / Nicotine administration in humans and rodents enhances memory and attention,
and also has a positive effect in Alzheimer's Disease. The Medial Septum / Diagonal
Band of Broca complex (MS/DBB) ? a main cholinergic system ? massively projects
to the hippocampus through the fimbria-fornix, and this pathway is called the septohippocampal
pathway. It has been demonstrated that the MS/DBB acts directly on
the local field potential (LFP) rhythmic organization of the hippocampus, especially in
the rhythmogenesis of Theta (4-8Hz) ? an oscillation intrinsically linked to
hippocampus mnemonic function. In vitro experiments gave evidence that nicotine
applied to the MS/DBB generates a local network Theta rhythm within the MS/DBB.
Thus, the present study proposes to elucidate the function of nicotine in the MS/DBB
on the septo-hippocampal pathway. In vivo experiments compared the effect of
MS/DBB microinfusion of saline (n=5) and nicotine (n=8) on Ketamine/Xylazine
anaesthetized mice. We observed power spectrum density in the Gamma range (35
to 55 Hz) increasing in both structures (Wilcoxon Rank-Sum test, p=0.038) but with
no change in coherence between these structures in the same range (Wilcoxon
Rank-Sum test, p=0.60). There was also a decrease in power of the ketamineinduced
Delta oscillation (1 to 3 Hz). We also performed in vitro experiments on the
effect of nicotine on membrane voltage and action potential. We patch-clamped 22
neurons in current-clamp mode; 12 neurons were responsive to nicotine, half of them
increased firing rate and other 6 decreased, and they significantly differed in action
potential threshold (-47.3?0.9 mV vs. -41?1.9 mV, respectively, p=0.007) and halfwidth
time (1.6?0.08 ms vs. 2?0.12 ms, respectively, p=0.01). Furthermore, we
performed another set of in vitro experiments concerning the connectivity of the three
major neuronal populations of MS/DBB that use acetylcholine, GABA or glutamate as
neurotransmitter. Paired patch-clamp recordings found that glutamatergic and
GABAergic neurons realize intra-septal connections that produce sizable currents in
MS/DBB postsynaptic neurons. The probability of connectivity between different
neuronal populations gave rise to a MS/DBB topology that was implemented in a
realistic model, which corroborates that the network is highly sensitive to the
generation of Gamma rhythm. Together, the data available in the full set of
experiments suggests that nicotine may act as a cognitive enhancer, by inducing
gamma oscillation in the local circuitry of the MS/DBB.
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Procedimentos para avaliação tecnológica de equipamentos médico-hospitalares : um estudo aplicado à hemodiáliseMagnago, Patrícia Flores January 2016 (has links)
A Avaliação Tecnológica em Saúde (ATS) é uma sistemática que avalia os impactos clínicos, sociais e econômicos das tecnologias em saúde e tem como finalidade auxiliar os gestores na tomada de decisão quanto ao desenvolvimento, incorporação e descontinuação destas tecnologias. Agências de ATS têm destacado a importância da existência de métodos que visem padronizar e implantar esta sistemática em diferentes contextos. Assim, o objetivo geral desta tese é propor procedimentos para apoiar a avaliação tecnológica de equipamentos médico-hospitalares, por meio de uma pesquisa construtiva (Constructive Research) aplicada à terapia de hemodiálise. Os procedimentos propostos compõem um modelo adaptado do EuroScan, modelo desenvolvido por agências Europeias e indicado como boa prática pelo Ministério da Saúde do Brasil. Também são procedimentos ajustados às necessidades de pesquisadores de centros regionais de avaliação de equipamentos médico-hospitalares. Inicialmente, foi desenvolvida uma coleta de dados sobre os problemas de desenvolvimento e incorporação das tecnologias da saúde por meio de duas fontes: uma revisão sistemática de literatura sobre oportunidades de melhorias do EuroScan no mundo e discussões com pesquisadores no país. A partir destas investigações foi proposto um modelo preliminar de ATS, aplicado para o domínio Operacional e de Inovação na hemodiálise. Finalmente a aplicação foi validada e examinada por especialistas para a geração de um modelo final. Os principais procedimentos resultantes foram: (i) validação da relevância das avaliações para novos desenvolvimentos e incorporações tecnológicas do ponto de vista de diferentes especialistas, integrando diferentes áreas do conhecimento na ATS; (ii) operação de Observatórios Tecnológicos, auxiliando na definição das tecnologias e domínios a serem avaliadas; (iii) definição de técnicas para análise dos domínios de ATS, como o uso de séries temporais e o Technology Roadmap (TRM) para previsões sobre o futuro das inovações e o uso das dimensões da usabilidade e de incidentes críticos de riscos para os aspectos operacionais; e (iv) integração das diretrizes de ATS no Brasil em um único modelo, amparando pesquisadores não relacionados a saúde na compreensão sobre ATS e no desenvolvimento ágil de novos estudos tanto para equipamentos emergentes como em uso. Já a avaliação dos domínios selecionados para a hemodiálise resultou: (i) na identificação de um crescimento médio anual de 7% dos indicadores da terapia; (ii) no diagnóstico de usabilidade de máquinas eficazes, porém com possibilidades de gerarem maior satisfação aos usuários quanto: ao espaço entre elas, a redução dos desperdícios de água e materiais, aos planos de manutenção para evitar temperaturas elevadas, a capacitação visando mais atenção e treinamento para tarefas de apoio e aos aspectos de display (realimentação de dados e visualização); e (iii) na consolidação entre profissionais sobre um futuro promissor, para os próximos 10 anos no Brasil, da assistência homecare com máquinas de hemodiálise portáteis, mais seguras e sustentáveis. / The Health Technology Assessment (HTA) is a systematic evaluation of clinical, social and economic impacts of health technologies aiming to assist managers in the decision making process related to the development, consolidation and discontinuation of these technologies. HTA agencies have been highlighting the importance of methods to standardize and apply this systematic evaluation in different contexts. Thus, the general objective of this thesis is to propose procedures to support the technology assessment of medical-hospital equipment through a constructive research applied to hemodialysis therapy. The proposed procedures compose a EuroScan adapted model, which was developed by European agencies and is recommended as a good practice by the Brazilian Ministry of Health, and also are procedures adjusted to the needs of researchers in regional centers of medical equipment assessment. Initially, a data collection on the problems of developing and incorporating health technologies was carried out using two sources: a systematic review of the literature on opportunities to improve the EuroScan around the world and discussions with Brazilian researchers. Based on these investigations, it was proposed a preliminary HTA model applied to the hemodialysis’ Operational and Innovation domain. The application of the model was reviewed and evaluated by experts to produce a final version. The main resulting procedures were: (i) to validate the importance of assessments for new technological developments and incorporations considering the point of view of different experts from diverse knowledge areas; (ii) to operate Technological Observatories, assisting to define the technologies and domains to be evaluated; (iii) to set techniques for the analysis of HTA domains such as the use of time series and the Technology Roadmap (TRM) to make predictions about the future of innovations and the use of usability dimensions and critical incidents of risks to the operational aspects; and (iv) to integrate HTA Brazilian guidelines in a single model, supporting researchers not related to health in the understanding of HTA and fast development of new studies for both emerging and in use equipment. The assessment of the domains selected for hemodialysis led to: (i) the identification of an annual growth in therapy indicators (7% in average); (ii) the usability diagnosis of efficient machines, however with the potential to generate greater user satisfaction considering: distance between machines, reduction in the waste of water and materials, maintenance plans to avoid high temperatures, training aiming more attention to supporting tasks as well as focus on display aspects (data feedback and visualization); and (iii) the consolidation among professionals of a future, for the next 10 years in Brazil, based on homecare with portable machines, safer and more sustainable.
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Českobudějovická periodika 1918-1939 (se zaměřením na vybranou problematiku) / Periodicals in České Budějovice from 1918 to 1939 (Focus on selected problems)KŘÍŽOVÁ, Petra January 2008 (has links)
The graduation theses deals with periodic newspapers of the region in Czech Budweis during the interwar period. Its aim is to evaluate the function of the regional media and give a survey of journalism of Czech Budweis of 1918-1939. Above all, it is focused on regional options of political parties papers, which are highlighted further on. In conclusion, it tries to outline topics suitable to be placed in medial education at the basic school.
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Efeitos da administração de canabidiol no CPFmv de ratos submetidos ao teste do nado forçado / Effects of cannabidiol administration into the vmPFC of rats submitted to the forced swimming testAriandra Guerini Sartim 19 March 2013 (has links)
A administração sistêmica de canabidiol (CBD), o principal constituinte não psicomimético da Cannabis sativa, induz efeito antidepressivo em modelos préclínicos. O mecanismo de ação do canabidiol, no entanto, permanece pouco conhecido, podendo envolver a ativação de receptores serotoninérgicos do tipo 1A (5-HT1A). Ademais, as estruturas encefálicas envolvidas nesses efeitos permanecem desconhecidas. O córtex pré-frontal medial ventral (CPFmv), dividido em infra-límbico (IL) e pré-límbico (PL), recebe densa inervação serotoninérgica e desempenha importante papel na modulação da resposta emocional ao estresse e na neurobiologia da depressão. Dessa forma, o objetivo do presente trabalho foi avaliar a hipótese de que a administração de canabidiol no CPFmv, diferenciado em PL e IL, produz efeito tipo-antidepressivo por meio da ativação de receptores 5- HT1A. Para tanto, ratos Wistar canulados bilateralmente no CPFmv, receberam CBD (10, 30, 60 nmol/0,2?l) ou veículo intra-PL e CBD (30, 45 e 60nmol/0,2?l) ou veículo intra-IL e foram submetidos ao teste do nado forçado ou ao teste do campo aberto. Outro grupo de animais recebeu microinjeção (intra PL ou IL) do agonista de receptores 5-HT1A, 8-OH-DPAT (5, 10nmol/0,2?l) e foram submetidos aos mesmos testes. Um grupo adicional recebeu um antagonista 5-HT1A, WAY1006365 (10, 30nmol/0,2?l), seguido pela administração de 8-OH-DPAT (10nmol0,2?l) ou CBD (10 nmol0,2?l) intra-PL, ou 8-OH-DPAT (10nmol0,2?l) ou CBD (45 nmol0,2?l) intra-IL, e avaliados no teste do nado forçado. Os resultados demonstraram que a administração de CBD e de 8-OH-DPAT, intra-PL e intra-IL, reduziu significativamente o tempo de imobilidade no teste do nado forçado, um efeito tipoantidepressivo, sem alterar a atividade locomotora dos animais no teste do campo aberto. Além disso, a administração de WAY100635 intra-PL e intra-IL não alterou o tempo de imobilidade per se, mas foi capaz de bloquear os efeitos da administração do CBD e do 8-OH-DPAT. Esses resultados sugerem que a administração local do CBD no CPFmv induz efeito tipo-antidepressivo por meio da ativação de receptores 5-HT1A. Portanto, é possível que o CPFmv esteja envolvido no efeito tipoantidepressivo induzido pelo CBD. / Systemic administration of cannabidiol (CBD), the main non-psychotomimetic constituent of Cannabis sativa, induces antidepressant-like effects in pre-clinical models. The mechanism of action of Cannabidiol, which remains poorly understood, may involve serotonergic type 1A receptors activation (5-HT1A). Furthermore, the brain structures involved in these effects are still unknown. The ventral medial prefrontal cortex (vmPFC), divided in infra-limbic (IL) and pre-limbic (PL) subregions, receives dense serotonergic innervation and plays an important role in the modulation of emotional responses to stress and in the neurobiology of depression. Thus, the aim of this study was evaluate the hypothesis that the administration of cannabidiol into the vmPFC, differentiated into IL and PL, would induce antidepressant-like effect by activating 5-HT1A receptors. Therefore, male Wistar rats with cannulae bilaterally implanted into the Il and PL were given CBD (10, 30, 45, 60 nmol/0,2?l) or vehicle and were submitted to the forced swimming test or to the open field test. Another group of animals received microinjections (intra PL or IL) of the 5- HT1A agonist 8-OH-DPAT (5, 10nmol/0,2?l) and was submitted to the same tests. An additional group received an 5-HT1A antagonist, WAY100635 (10, 30 nmol/0,2?l.), followed by the administration of 8-OH-DPAT (10 nmol/0,2?l) or CBD (10 nmol0,2?l) intra-PL, or 8-OH-DPAT (10nmol0,2?l) or CBD (45 nmol0,2?l) intra- IL, and avaluated in the forced swimming test. The results showed that CBD and 8- OH-DPAT administration, intra-PL and intra-IL, significantly reduced the immobility time in the forced swimming test, an antidepressant-like effect, without changing the locomotor activity of the animals in the open field test. Moreover, the administration of WAY100635, intra-PL and intra-IL, did not change the immobility time per se, but blocked the CBD- and 8-OH-DPAT-induced effects. These results suggest that the local administration of CBD into the vmPFC induces antidepressant-like effects through the activation of 5-HT1A receptors. Therefore, it is possible that the vmPFC is involved in CBD-induced antidepressant-like effect.
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Surrogatmödraskap - en frihet eller ett förtryck? : En kombinerad kvalitativ & kvantitativ studie över debatten kring surrogatmödraskapsförbudet i Indien under hösten 2016 på sju av Indiens största nyhetssajter.Malm, Angelica January 2017 (has links)
No description available.
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Role of prefrontal cortex dopamine in associative learning / Rôle de la dopamine du cortex préfrontal dans l'apprentissage associatifAly Mahmoud, Mayada 19 June 2017 (has links)
La dopamine du cortex préfrontal (PFC) est impliquée dans l’apprentissage et dans la prise de décision liée à l’effort. Comme l’apprentissage ne peut se faire sans effort, il n’est pas clair aujourd’hui si la dopamine est nécessaire pour l’apprentissage, ou pour l’engagement de l’effort pour apprendre. Dans ce travail, les rats apprenaient à pousser un levier pour obtenir de la nourriture, soit avec (apprentissage par observation, LeO) ou sans (essai-et-erreur, TE) observation préalable d’un congénère exécutant la tâche. TE et la phase d’exécution de LeO nécessitent l’effort physique (overt learning), l’observation dans LeO ne requiert pas d’effort physique (covert learning). Avant chaque session, les rats recevaient des injections de SCH23390 ou de la saline dans le cingulaire antérieur (ACC) ou l’orbitofrontal (OFC). Si la dopamine est nécessaire à l’apprentissage, le blocage des récepteurs D1 affecterait aussi bien l’apprentissage overt que covert. Si la dopamine n’est pas requise pour l’apprentissage mais pour l’engagement de l’effort, le blocage affecterait l’apprentissage overt, et non covert. Les résultats montrent que le blocage de la dopamine dans ACC ou OFC supprime l’apprentissage overt, laissant intact l’apprentissage covert. Une fois les injections arrêtées, les rats récupèrent la capacité d’apprendre, mais dans le cas de ACC, pas la tolérance à l’effort. Ces résultats suggèrent que la dopamine dans ACC et OFC n’est pas nécessaire pour l’apprentissage, et que les déficits d’apprentissage pourraient reflèter une réduction de la tolérance effort à l’effort liée au blocage de la dopamine. / Because prefrontal cortex (PFC) dopamine plays a pivotal role in associative learning and in effort-related decision making, it is not clear as of today whether PFC dopamine activity is required for learning per se, or rather for engaging the effort necessary to learn. In this work, we used observational learning (LeO) and trial-and-error (TE) learning to dissociate learning from physical effort. Both TE and the execution phase of LeO require physical effort (overt learning). Observation does not require physical effort (covert learning). Rats learned to push a lever for food rewards either with or without prior observation of an expert conspecific performing the same task. Before daily testing sessions, the rats received bilateral ACC or OFC microinfusions of SCH23390, or saline-control infusions. If dopamine activity is required for task acquisition, its blockade should impair both overt and covert learning. If dopamine is not required for task acquisition, but solely for regulating effort tolerance, blockade should impair overt learning but spare covert learning. We found that dopamine blockade in ACC or OFC suppressed overt learning selectively, leaving covert learning intact. In subsequent testing sessions without dopamine blockade, rats recovered their overt-learning capacity but, in ACC experiments, the animals did not recover their normal level of effort tolerance. These results suggest that ACC and OFC dopamine is not required for the acquisition of conditioned behaviours and that apparent learning impairments could instead reflect a reduced level of effort tolerance due to cortical dopamine blockade.
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Effect of Anterior or Ventromedial Hypothalamic Stimulation on Immunoglobulin GLambert, Paul L. (Paul Louis) 08 1900 (has links)
Although research has linked central nervous system activity with changes in immunoresponsivity, research on the possible role of the central nervous system in altering a specific class of antibody is lacking. This study was an investigation of the possible relationship between anterior or medial hypothalamic functions on Immunoglobulin G. concentrations in rat serum. Thirty-six male albino rats were randomly assigned to
three groups of equal size. Animals within the anterior hypothalamic group received bilateral electrode implants in the anterior hypothalamus while animals in the medial hypothalamic group received electrode implants within the ventromedial area of the hypothalamus. A control group received bilateral electrode implants within the lateral hypothalamus. Electrical brain stimulation was administered to animals in both experimental groups. Control animals spent a comparable time in an operant chamber but did not receive electrical brain stimulation. Following brain stimulation of animals within the experimental groups, Immunoglobulin G. concentrations were determined for all groups 3, 6, 12, and 24 hours post-stimulation sessions.
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Betrachtungen zur Skelettextraktion umformtechnischer BauteileKühnert, Tom, Brunner, David, Brunnett, Guido 08 April 2011 (has links) (PDF)
Die Skelettextraktion ist besonders in der Formanalyse ein wichtiges Werkzeug. Im Rahmen des Forschungsprojektes ’Extraktion fertigungsrelevanter Merkmale aus 3D-Daten umformtechnischer Bauteile zur featurebasierten Fertigungsprozessgestaltung’ als Kooperationsprojekt zwischen der Professur Graphische Datenverarbeitung und Visualisierung an der Technischen Universität Chemnitz und des Fraunhofer-Institut für Werkzeugmaschinen und Umformtechnik Chemnitz wurde diese zur Featureerkennung umgesetzt. Dieses Dokument gibt zunächst Einblick in grundlegende Verfahren und Problemstellungen einer solchen Extraktion. Die Ergebnisse mehrerer Forschungsschwerpunkte, die sich aus den zu untersuchenden Massivumformteilen ergaben, werden vorgestellt. Hierbei besonders interessant ist die robuste Extraktion von Kurvenskeletten bei Bauteilen mit nicht-zylindrischer Hauptform, sowie bei Bauteilen mit Nebenformelementen. Desweiteren werden Nachverarbeitung und Auswertung des Kurvenskeletts, sowie verwandte Forschungsarbeiten und -ergebnisse diskutiert.
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Effect of prolonged contralateral acoustic stimulation on TEOAE suppressionVan Zyl, Altelani 30 November 2009 (has links)
Although the suppressive effect of the medial olivocochlear system (MOCS) on peripheral auditory active mechanisms is well documented in humans, the effect of efferent inhibition over prolonged periods of acoustic stimulation is less well documented, especially as observed in suppression of transient evoked otoacoustic emissions (TEOAE’s). The present study therefore evaluated the relationship between the duration of contralateral acoustic stimulation and the suppression of TEOAE’s in ten adults with normal hearing. TEOAE recordings with linear clicks (60 dB sound pressure level) were measured at four intervals during 15 minutes of continuous contralateral white noise (45 dB sound pressure level), followed by two post-noise recordings. An identical within-subject control condition was recorded without contralateral noise. Experimental and control measurements were repeated three times, on separate days. Results revealed significant and sustained TEOAE amplitude reduction for the entire duration of contralateral stimulation. Suppression increased across the duration of contralateral noise, but not sufficiently to be statistically significant. After noise termination, TEOAE amplitudes increased to values significantly above control recordings. The sustained suppression of TEOAE’s indicates continuous efferent inhibition over time in normal adults, with a significant increase in TEOAE amplitude after noise cessation possibly indicating increased outer hair cell responsiveness after prolonged contralateral noise. / Dissertation (MCommunication Pathology)--University of Pretoria, 2009. / Speech-Language Pathology and Audiology / Unrestricted
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