996 resultados para 304-2


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Magnetic susceptibility and ice-rafted debris of surface sediments in the Nordic Seas were investigated to reconstruct source areas and recent transport pathways of magnetic minerals. From the distribution of magnetic susceptibility and ice-rafted debris and published data on petrographic tracers for iceberg drift, we reconstructed a counter-clockwise iceberg drift pattern during cooler phases in the Holocene, which is similar to conceptual and numerical models for Weichselian iceberg drift. The release of basaltic debris at Scoresby Sund played a significant role for the magnetic signature of stadial/interstadial events during isotope stage 3 recorded in sediment cores of the Nordic Seas.

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In this dissertation, there are developed different analytical strategies to discover and characterize mammalian brain peptides using small amount of tissues. The magnocellular neurons of rat supraoptic nucleus in tissue and cell culture served as the main model to study neuropeptides, in addition to hippocampal neurons and mouse embryonic pituitaries. The neuropeptidomcis studies described here use different extraction methods on tissue or cell culture combined with mass spectrometry (MS) techniques, matrix-assisted laser desorption/ionization (MALDI) and electrospray ionization (ESI). These strategies lead to the identification of multiple peptides from the rat/mouse brain in tissue and cell cultures, including novel compounds One of the goals in this dissertation was to optimize sample preparations on samples isolated from well-defined brain regions for mass spectrometric analysis. Here, the neuropeptidomics study of the SON resulted in the identification of 85 peptides, including 20 unique peptides from known prohormones. This study includes mass spectrometric analysis even from individually isolated magnocellular neuroendocrine cells, where vasopressin and several other peptides are detected. At the same time, it was shown that the same approach could be applied to analyze peptides isolated from a similar hypothalamic region, the suprachiasmatic nucleus (SCN). Although there were some overlaps regarding the detection of the peptides in the two brain nuclei, different peptides were detected specific to each nucleus. Among other peptides, provasopressin fragments were specifically detected in the SON while angiotensin I, somatostatin-14, neurokinin B, galanin, and vasoactive-intestinal peptide (VIP) were detected in the SCN only. Lists of peptides were generated from both brain regions for comparison of the peptidome of SON and SCN nuclei. Moving from analysis of magnocellular neurons in tissue to cell culture, the direct peptidomics of the magnocellular and hippocampal neurons led to the detection of 10 peaks that were assigned to previously characterized peptides and 17 peaks that remain unassigned. Peptides from the vasopressin prohormone and secretogranin-2 are attributed to magnocellular neurons, whereas neurokinin A, peptide J, and neurokinin B are attributed to cultured hippocampal neurons. This approach enabled the elucidation of cell-specific prohormone processing and the discovery of cell-cell signaling peptides. The peptides with roles in the development of the pituitary were analyzed using transgenic mice. Hes1 KO is a genetically modified mouse that lives only e18.5 (embryonic days). Anterior pituitaries of Hes1 null mice exhibit hypoplasia due to increased cell death and reduced proliferation and in the intermediate lobe, the cells differentiate abnormally into somatotropes instead of melanotropes. These previous findings demonstrate that Hes1 has multiple roles in pituitary development, cell differentiation, and cell fate. AVP was detected in all samples. Interestingly, somatostatin [92-100] and provasopressin [151-168] were detected in the mutant but not in the wild type or heterozygous pituitaries while somatostatin-14 was detected only in the heterozygous pituitary. In addition, the putative peptide corresponding to m/z 1330.2 and POMC [205-222] are detected in the mutant and heterozygous pituitaries, but not in the wild type. These results indicate that Hes1 influences the processing of different prohormones having possible roles during development and opens new directions for further developmental studies. This research demonstrates the robust capabilities of MS, which ensures the unbiased direct analysis of peptides extracted from complex biological systems and allows addressing important questions to understand cell-cell signaling in the brain.

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La legge n.354 del 1975 ha apportato importanti cambiamenti nella vita detentiva. Viene messa in luce un nuovo senso della sanzione: una pena più umana in cui il detenuto non può più essere considerato un soggetto da diagnosticare, ma da conoscere e reinserire nel contesto sociale. Tuttavia il carcere resta una realtà complessa piena di problematiche e contraddizioni. Il seguente lavoro ha cercato di comprendere l’opinione dei detenuti su tematiche che quotidianamente ruotano intorno al carcere: recidiva, finalità rieducativa e sorveglianza dinamica. A tal proposito è stato somministrato un questionario appositamente strutturato su tali tematiche ad un campione di 161 detenuti. Il carcere aperto e la sorveglianza dinamica risultano una nuova conquista trattamentale. Solo un carcere più vivibile, pieno di opportunità può realmente rieducare il soggetto ed insegnargli ad essere libero nel rispetto della legge.

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Il numero di nuove sostanze psicoattive (NSP) acquistabile in internet e le informazioni relative alla loro modalità di assunzione a scopi curativi, ricreazionali e spirituali, stanno aumentando costantemente. Nomi come “legal highs”, “herbal highs” e “etno-drugs”, inducono i consumatori a credere che questi prodotti siano sicuri e naturali, sottostimandone o volutamente trascurandone le loro potenzialità farmaco-tossicologiche. Oltre a questo, l’impiego di sostanze naturali tradizionalmente impiegate all’interno di un rituale ben definito in etnie specifiche, in nuovi contesti ricreativi, porta spesso all’abuso delle stesse sostanze (Marti, 2013; 2015). Infatti, mentre l’uso tradizionale/etnico di queste sostanze naturali, non sembra essere associato a dipendenza, intossicazioni o problemi legati alla salute, una volta raggiunto il mercato mondiale, si assiste invece ad una escalation di problematiche ed intossicazioni. Queste derivano soprattutto dal fatto che uscendo da un contesto tradizionale per accedere in uno prettamente ricreazionale, cambiano numerosi fattori fondamentali tra cui: la via di somministrazione, la quantità assunta, l’assunzione di sostanze pure e la co-somministrazione con altre sostanze psicoattive.

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The literature around Library 2.0 remains largely theoretical with few empirically studies and is particularly limited in developing countries such as Indonesia. This study addresses this gap and aims to provide information about the current state of knowledge on Indonesian LIS professionals’ understanding of Library 2.0. The researchers used qualitative and quantitative approaches for this study, asking thirteen closed- and open-ended questions in an online survey. The researchers used descriptive and in vivo coding to analyze the responses. Through their analysis, they identified three themes: technology, interactivity, and awareness of Library 2.0. Respondents demonstrated awareness of Library 2.0 and a basic understanding of the roles of interactivity and technology in libraries. However, overreliance on technology used in libraries to conceptualize Library 2.0 without an emphasis on its core characteristics and principles could lead to the misalignment of limited resources. The study results will potentially strengthen the research base for Library 2.0 practice, as well as inform LIS curriculum in Indonesia so as to develop practitioners who are able to adapt to users’ changing needs and expectations. It is expected that the preliminary data of this study could be used to design a much larger and more complex future research project in this area.