103,394 research outputs found
Anticipation of novelty recruits reward system and hippocampus while promoting recollection
No full textThe dopaminergic midbrain, which comprises the substantia nigra and ventral tegmental area (SN/VTA), plays a central role in reward processing. This region is also activated by novel stimuli, raising the possibility that novelty and reward have shared functional properties. It is currently unclear whether functional aspects of reward processing in the SN/VTA, namely, activation by unexpected rewards and cues that predict reward, also characterise novelty processing. To address this question, we conducted an fMRI experiment during which subjects viewed symbolic cues that predicted either novel or familiar images of scenes with 75% validity. We show that SN/VTA was activated by cues predicting novel images as well as by unexpected novel images that followed familiarity-predictive cues, an 'unexpected novelty' response. The hippocampus, a region implicated in detecting and encoding novel stimuli, showed an anticipatory novelty response but differed from the response profile of SN/VTA in responding at outcome to expected and 'unexpected' novelty. In a behavioural extension of the experiment, recollection increased relative to familiarity when comparing delayed recognition memory for anticipated novel stimuli with unexpected novel stimuli. These data reveal commonalities in SN/VTA responses to anticipating reward and anticipating novel stimuli. We suggest that this anticipatory response codes a motivational exploratory novelty signal that, together with anticipatory activation of the hippocampus, leads to enhanced encoding of novel events. In more general terms, the data suggest that dopaminergic processing of novelty might be important in driving exploration of new environments
A ferrovia no Vale do Itajaí
No full textDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-graduação em Urbanismo, História e Arquitetura da CidadeO tema desta dissertação é uma análise dos fatos históricos relacionados ao processo de implantação e à posterior desativação da EFSC no Vale do Itajaí, destacando os principais agentes do processo e a conseqüência de suas ações no domínio geográfico e social. Esta pesquisa tem sua relevância social e acadêmica como instrumento de pesquisa e de memória baseado na organização dos fatos históricos desencadeados em torno dos transportes no Vale do Itajaí, com foco para o transporte ferroviário, uma vez que há pouca publicação e pesquisa sobre a EFSC. O trabalho foi referenciado pela análise das relações sociais sob os conceitos de Santos (1991), de fatos históricos registrados em periódicos, documentos escritos, fotográficos e cartográficos, entrevistas e, quando necessário, pela busca da contextualização dentro dos acontecimentos nacionais e internacionais, para melhor esclarecimento dos fatos em escala local e regional. Além disso, esta pesquisa usou como referência a análise e os conceitos de Mumford, em sua obra A Cidade na História, abordando o processo de transformações urbanas decorrente do desenvolvimento das cidades e seus principais agentes. Conceitos de outros autores, como Villaça, Lefebvre e Halbwachs são igualmente suportes teóricos deste trabalho. A ferrovia fez parte dos planos das lideranças locais, desde as primeiras décadas de história da fundação dos núcleos urbanos na região da bacia do Itajaí, como questão básica para o desenvolvimento econômico da região. The theme of this thesis is an analysis of historical facts related to the process of implantation and further disabling of EFSC (Estrada de Ferro Santa Catarina) in the region of Vale do Itajaí, State of Santa Catarina, highlighting the main agents of the case and the consequences of their actions both on geographical and social domain. This research has a social and academic relevance as a tool for further search and memory since it presents the organization of historical facts regarding transport in the region of Vale do Itajaí, with a focus on railway transportation, especially EFSC, from which little research sources and publications can be found. The work is referenced by an analysis of social relations according to the concepts of Santos (1991); historical facts recorded in journals, written, photographic, cartographic documents; and interviews. It includes, also, some search on the context of national and international events in order to offer a better understanding of the facts in a local and regional scale. Additionally, this research used as a reference to the concepts shown an analysis registered by Mumford in his book "A Cidade na História", around the process of urban transformations resulting from the development of cities and their key players. Concepts of other authors, as Villaça, Lefebvre and Halbwachs are also devices of this theoretical work. The railway took part of the local leaders' plans since the first decades of the history of the foundation of urban areas located at the basin of the Itajaí River. It was, at that time, a basic need for the economic development of the region
Activated human T lymphocytes express a functional C3a receptor
No full textThe C3a molecule is an anaphylatoxin of the C system with a wide spectrum of proinflammatory effects predominantly an cells of myeloid origin. In this study we investigated the expression of the high affinity receptor for C3a (C3aR) in human T lymphocytes using receptor-specific mAb, C3aR expression was detected in CD4(+) and CD8(+) blood- or skin-derived T cell clones (TCC) from birch pollen-sensitized patients with atopic dermatitis. No significant difference in C3aR expression in CD4(+) or CD8(+) TCCs could be observed, In contrast to C3a(desArg), C3a led to a transient calcium flux in TCCs expressing the C3aR, whereas C3aR-negative TCCs were unreactive, Circulating T cells from patients suffering from severe inflammatory skin diseases expressed the C3aR, whereas no expression of C3aR could be found in unstimulated T lymphocytes from patients with mild inflammatory skin diseases or from healthy individuals. Type I IFNs, which are potent stimulators of cellular immunity, were identified as up-regulators of C3aR expression in vitro in freshly isolated or cloned T lymphocytes. Moreover, C3aR(+) T cells were found at the sites of injection in IPN-beta -treated patients with multiple sclerosis. These data provide direct evidence for the expression of C3aR on activated human T lymphocytes; this may point to a biological function of C3a in T cell-dependent diseases
Activated human T lymphocytes express a functional C3a receptor
No full textThe C3a molecule is an anaphylatoxin of the C system with a wide spectrum of proinflammatory effects predominantly an cells of myeloid origin. In this study we investigated the expression of the high affinity receptor for C3a (C3aR) in human T lymphocytes using receptor-specific mAb, C3aR expression was detected in CD4(+) and CD8(+) blood- or skin-derived T cell clones (TCC) from birch pollen-sensitized patients with atopic dermatitis. No significant difference in C3aR expression in CD4(+) or CD8(+) TCCs could be observed, In contrast to C3a(desArg), C3a led to a transient calcium flux in TCCs expressing the C3aR, whereas C3aR-negative TCCs were unreactive, Circulating T cells from patients suffering from severe inflammatory skin diseases expressed the C3aR, whereas no expression of C3aR could be found in unstimulated T lymphocytes from patients with mild inflammatory skin diseases or from healthy individuals. Type I IFNs, which are potent stimulators of cellular immunity, were identified as up-regulators of C3aR expression in vitro in freshly isolated or cloned T lymphocytes. Moreover, C3aR(+) T cells were found at the sites of injection in IPN-beta -treated patients with multiple sclerosis. These data provide direct evidence for the expression of C3aR on activated human T lymphocytes; this may point to a biological function of C3a in T cell-dependent diseases
Michel Wittmann et Claude Thouvenot, La Mutation de la sidérurgie
No full textPrêcheur Claude. Michel Wittmann et Claude Thouvenot, La Mutation de la sidérurgie. In: Annales de Géographie, t. 83, n°459, 1974. pp. 594-595
Géographie de la métallurgie de transformation, C. thouvenot, M. Wittmann
No full textGeorge Pierre. Géographie de la métallurgie de transformation, C. thouvenot, M. Wittmann. In: Annales de Géographie, t. 86, n°477, 1977. p. 601
Gesundheit im Kinders- und Jugendalter: die Relevanz der Geschlechterperspektive
No full textKolip P. Gesundheit im Kinders- und Jugendalter: die Relevanz der Geschlechterperspektive. In: Wittmann S, Rauschenbach T, Leu HR, eds. Kinder in Deutschland. Eine Bilanz empirischer Studien. Weinheim: Juventa; 2011: 142-146
Veronika Wittmann, Weltgesellschaft. Rekonstruktion eines wissenschaftlichen Diskurses. Baden-Baden: Nomos 2014, 371 S., br., 69,00 €
No full textWerron T. Veronika Wittmann, Weltgesellschaft. Rekonstruktion eines wissenschaftlichen Diskurses. Baden-Baden: Nomos 2014, 371 S., br., 69,00 €. Soziologische Revue. 2017;40(1)
Über Strukturen und Überstrukturen
No full textLindel T, Sewald N, Wittmann V. Über Strukturen und Überstrukturen. Nachrichten aus Chemie, Technik und Laboratorium. 1999;47(1):16-20
Herpesvirus saimiri-transformed macaque T cells are tolerated and do not cause lymphoma after autologous reinfusion
No full textHuman T cells are transformed in vitro to stable growth after infection with herpesvirus saimiri subgroup C strain C488, and they retain their antigen-specific reactivity and other important functional features of mature activated T lymphocytes. The virus persists as nonintegrating episomes in human T cells under restricted viral gene expression and without production of virus particles. This study analyzes the behavior of herpesvirus-transformed autologous T cells after reinfusion into the donor under close-to-human experimental conditions. T cells of 5 macaque monkeys were transformed to stable interleukin-2 dependent growth and were intravenously infused into the respective donor. The animals remained healthy, without occurrence of lymphoma or leukemia for an observation period of more than 1 year. Over several months virus genomes were detectable in peripheral blood cells and in cultured T cells by polymerase chain reaction. In naive control animals, a high-dose intravenous infection rapidly induced pleomorphic peripheral T-cell lymphoma. In contrast, monkeys were protected from lymphoma after challenge infection if they had previously received autologous T-cell transfusions. High levels of antibodies against virus antigens were detectable after challenge infection only. Taken together, herpesvirus-transformed T cells are well tolerated after autologous reinfusion. This may allow us to develop a novel concept for adoptive T-cell mediated immunotherapy
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