927 resultados para Earth’s early history
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Controversy over the alpine route that Hannibal of Carthage followed from the Rhône Basin into Italia has raged amongst classicists and ancient historians for over two millennia. The motivation for identifying the route taken by the Punic Army through the Alps lies in its potential for identifying sites of historical archaeological significance and for the resolution of one of history's most enduring quandaries. Here, we present stratigraphic, geochemical and microbiological evidence recovered from an alluvial floodplain mire located below the Col de la Traversette (~3000 m asl-above sea level) on the French/Italian border that potentially identifies the invasion route as the one originally proposed by Sir Gavin de Beer (de Beer 1974). The dated layer is termed the MAD bed (mass animal deposition) based on disrupted bedding, greatly increased organic carbon and key/specialized biological components/compounds, the latter reported in Part II of this paper. We propose that the highly abnormal churned up (bioturbated) bed was contaminated by the passage of Hannibal's animals, possibly thousands, feeding and watering at the site, during the early stage of Hannibal's invasion of Italia (218 bc).
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s a signatory to the Boxer Protocol in 1901, Italy came into possession of the Tianjin concession, its only colonial possession in China. The Italian settlement was situated on the Hai River, and most of the land consisted of cemeteries and salt deposits. Italian administration of the settlement encountered many difficulties. Expropriation of land from the Chinese occupants was not easy, and it proved equally difficult to attract Italian investors. However despite the fact that Italian public opinion supported the abandonment of the concession, the Italian government was ultimately obliged to undertake a project for its urban development. Success in Tianjin became a national challenge for Italy, with the National Trust providing the necessary economic support. The history of the Italian settlement in Tianjin therefore sheds light on the politics of colonialism and on Italy's economic and political agendas at the turn of the twentieth century.
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Partendo da un’analisi dei problemi che si incontrano nella fase di conceptual design, si presentano le diverse tecniche di modellazione tridimensionale, con particolare attenzione al metodo subdivision e agli algoritmi che lo governano (Chaikin, Doo – Sabin). Vengono poi proposti alcuni esempi applicativi della modellazione free form e skeleton, con una successiva comparazione, sugli stessi modelli, delle sequenze e operazioni necessarie con le tradizionali tecniche di modellazione parametrica. Si riporta un esempio dell’utilizzo del software IronCAD, il primo software a unire la modellazione parametrica e diretta. Si descrivono le limitazioni della modellazione parametrica e di quella history free nella fase concettuale di un progetto, per arrivare a definire le caratteristiche della hybrid modeling, nuovo approccio alla modellazione. Si presenta brevemente il prototipo, in fase di sviluppo, che tenta di applicare concretamente i concetti dell’hybrid modeling e che vuole essere la base di partenza per una nuova generazione di softwares CAD. Infine si presenta la possibilità di ottenere simulazioni real time su modelli che subiscono modifiche topologiche. La simulazione real time è permessa dalla ridefinizione in forma parametrica del problema lineare elastico che viene successivamente risolto mediante l’applicazione congiunta delle R – Functions e del metodo PGD. Seguono esempi di simulazione real time.
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Background Individual placement and support (IPS) is effective in helping patients return to work but is poorly implemented because of clinical ambivalence and fears of relapse. Aims To assess whether a motivational intervention (motivational interviewing) directed at clinical staff to address ambivalence about employment improved patients’ occupational outcomes. Method Two of four early intervention teams that already provided IPS were randomised to receive motivational interviewing training for clinicians, focused on attitudinal barriers to employment. The trial was registered with the International Standard Randomised Controlled Trial Register (ISRCTN71943786). Results Of 300 eligible participants, 159 consented to the research. Occupational outcomes were obtained for 134 patients (85%) at 12-month follow-up. More patients in the intervention teams than in the IPS-only teams achieved employment by 12 months (29/68 v. 12/66). A random effects logistic regression accounting for clustering by care coordinator, and adjusted for participants’ gender, ethnicity, educational and employment history and clinical status scores, confirmed superiority of the intervention (odds ratio = 4.3, 95% CI 1.5-16.6). Conclusions Employment outcomes were enhanced by addressing clinicians’ ambivalence about their patients returning to work.
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New challenges posed by global environmental change have motivated scholars to pay growing attention to historical long-term strategies to deal with climate extremes. We aim to understand long-term trends in community responses to cope with droughts, to explain how many preindustrial societies coevolved with local hydro-climatic dynamics and coped with climate extremes over time. The specific goals of this work are: (1) to analyze how local communities experienced droughts over long periods of time and (2) to document the spectrum of recorded community responses to drought. Our research covers over one century (1605-1710) of responses to drought in the community of Terrassa, Barcelona, Spain. Data were collected through archival research. We reviewed and coded 2076 village council minutes. Our results show that the local community adopted a mixture of symbolic, institutional, and infrastructural responses to drought and that drought-related decisions varied through time. We discuss adaptation strategies on the basis of the distinct physical signals of drought propagation and the role of nonclimatic historical factors, such as warfare and public debt, in shaping responses. We conclude that long-term perspectives on premodern history and comparable empirical studies are fundamental to advance our understanding of past social responses to hydro-climatic extremes.
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A history of specialties in economics since the late 1950s is constructed on the basis of a large corpus of documents from economics journals. The production of this history relies on a combination of algorithmic methods that avoid subjective assessments of the boundaries of specialties: bibliographic coupling, automated community detection in dynamic networks, and text mining. These methods uncover a structuring of economics around recognizable specialties with some significant changes over the period covered (1956–2014). Among our results, especially noteworthy are (1) the clear-cut existence of ten families of specialties, (2) the disappearance in the late 1970s of a specialty focused on general economic theory, (3) the dispersal of the econometrics-centered specialty in the early 1990s and the ensuing importance of specific econometric methods for the identity of many specialties since the 1990s, and (4) the low level of specialization of individual economists throughout the period in contrast to physicists as early as the late 1960s.
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Terrestrial planets produce crusts as they differentiate. The Earth’s bi-modal crust, with a high-standing granitic continental crust and a low-standing basaltic oceanic crust, is unique in our solar system and links the evolution of the interior and exterior of this planet. Here I present geochemical observations to constrain processes accompanying crustal formation and evolution. My approach includes geochemical analyses, quantitative modeling, and experimental studies. The Archean crustal evolution project represents my perspective on when Earth’s continental crust began forming. In this project, I utilized critical element ratios in sedimentary records to track the evolution of the MgO content in the upper continental crust as a function time. The early Archean subaerial crust had >11 wt. % MgO, whereas by the end of Archean its composition had evolved to about 4 wt. % MgO, suggesting a transition of the upper crust from a basalt-like to a more granite-like bulk composition. Driving this fundamental change of the upper crustal composition is the widespread operation of subduction processes, suggesting the onset of global plate tectonics at ~ 3 Ga (Abstract figure). Three of the chapters in this dissertation leverage the use of Eu anomalies to track the recycling of crustal materials back into the mantle, where Eu anomaly is a sensitive measure of the element’s behavior relative to neighboring lanthanoids (Sm and Gd) during crustal differentiation. My compilation of Sm-Eu-Gd data for the continental crust shows that the average crust has a net negative Eu anomaly. This result requires recycling of Eu-enriched lower continental crust to the mantle. Mass balance calculations require that about three times the mass of the modern continental crust was returned into the mantle over Earth history, possibly via density-driven recycling. High precision measurements of Eu/Eu* in selected primitive glasses of mid-ocean ridge basalt (MORB) from global MORs, combined with numerical modeling, suggests that the recycled lower crustal materials are not found within the MORB source and may have at least partially sank into the lower mantle where they can be sampled by hot spot volcanoes. The Lesser Antilles Li isotope project provides insights into the Li systematics of this young island arc, a representative section of proto-continental crust. Martinique Island lavas, to my knowledge, represent the only clear case in which crustal Li is recycled back into their mantle source, as documented by the isotopically light Li isotopes in Lesser Antilles sediments that feed into the fore arc subduction trench. By corollary, the mantle-like Li signal in global arc lavas is likely the result of broadly similar Li isotopic compositions between the upper mantle and bulk subducting sediments in most arcs. My PhD project on Li diffusion mechanism in zircon is being carried out in extensive collaboration with multiple institutes and employs analytical, experimental and modeling studies. This ongoing project, finds that REE and Y play an important role in controlling Li diffusion in natural zircons, with Li partially coupling to REE and Y to maintain charge balance. Access to state-of-art instrumentation presented critical opportunities to identify the mechanisms that cause elemental fractionation during laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analysis. My work here elucidates the elemental fractionation associated with plasma plume condensation during laser ablation and particle-ion conversion in the ICP.
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This thesis addresses a range of research questions regarding literacy in early modern Scotland. Using the early modern manuscripts and printed editions of Robert Lindsay of Pitscottie’s late sixteenth-century 'Cronicles of Scotland' as a case study on literacy history, this thesis poses the complementary questions of how and why early modern Scottish reading communities were encountering Pitscottie’s 'Cronicles', and how features of the material page can be interpreted as indicators of contemporary literacy practices. The answers to these questions then provide the basis for the thesis to ask broader socio-cultural and theoretical questions regarding the overall literacy environment in Scotland between 1575 and 1814, and how theorists conceptualise the history of literacy. Positioned within the theoretical groundings of historical pragmatics and ‘new philology’ – and the related approach of pragmaphilology – this thesis returns to the earlier philological practice of close textual analysis, and engages with the theoretical concept of mouvance, in order to analyse how the changing ‘form’ of Pitscottie’s 'Cronicles', as it was reproduced in manuscript and print throughout the early modern period, indicates its changing ‘function’. More specifically, it suggests that the punctuation practices and paratextual features of individual witnesses of the text function to aid the highly-nuanced reading practices and purposes of the discrete reading communities for which they were produced. This thesis includes extensive descriptive material which presents previously unrecorded data regarding twenty manuscripts and printed witnesses of Pitscottie’s 'Cronicles', contributing to a gap in Scotland’s literary/historiographical canon. It then analyses this material using a transferable methodological framework which combines the quantitative analysis of micro-data with qualitative analysis of this data within its socio-cultural context, in order to conduct diachronic comparative analysis of copy-specific information. The principal findings of this thesis suggest that Pitscottie’s 'Cronicles' were being read for a combination of devotional and didactic purposes, and that multiple reading communities, employing highly nuanced reading practices, were encountering the text near-contemporaneously. This thesis further suggests that early modern literacy practices, and the specific reading communities which employ them, should be described as existing within a spectrum of available practices (i.e. more or less oral/aural or silent, and intensive or extensive in practice) rather than as dichotomous entities. As such, this thesis argues for the rejection of evolutionary theories of the history of literacy, suggesting that rather than being described antithetically, historical reading practices and purposes must be recognised as complex, coexisting socio-cultural practices, and the multiplicity of reading communities within a single society must be acknowledged and analysed as such, as opposed to being interpreted as universal entities.
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This thesis represents the first extensive critical study of the relationship between Robert Burns and the early United States of America. Spanning literature, history and memory studies, the following chapters take an interdisciplinary approach towards investigating the methods by which Burns and his works rose to prominence and came to be of cultural and literary significance in America. Theoretically, these converging disciplines intersect through a transnational, Atlantic Studies perspective that shifts emphasis from Burns as the 'national poet of Scotland' onto the various socio-cultural connections that facilitated the spread of his work and reputation. In addition to Scottish literary studies, the thesis contributes to the broader fields of Transatlantic, Transnational and American Studies. Previous studies have suggested that Burns's popularity in the early United States might be attributed to his kinship with 'national' American ideals of freedom, egalitarianism and individual liberty. While some of the evidence supports this claim, this thesis argues that it also wrongly assumes a spatiotemporal unity for the nineteenth-century American nation. It concludes by suggesting that future critical studies of the poet must heed the multifarious complexities of 'national' paradigms, pointing the way to further work on the reception and influence of Burns in other 'global' or, indeed, transnational contexts.
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Bibliographical footnotes.
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A key aspect underpinning life-history theory is the existence of trade-offs. Trade-offs occur because resources are limited, meaning that individuals cannot invest in all traits simultaneously, leading to costs for traits such as growth and reproduction. Such costs may be the reason for the sub-maximal growth rates that are often observed in nature, though the fitness consequences of these costs would depend on the effects on lifetime reproductive success. Recently, much attention has been given to the physiological mechanism that might underlie these life-history trade-offs, with oxidative stress (OS) playing a key role. OS is characterised by a build-up of oxidative damage to tissues (e.g. protein, lipids and DNA) from attack by reactive species (RS). RS, the majority of which are by-products of metabolism, are usually neutralised by antioxidants, however OS occurs when there is an imbalance between the two. There are two main theories linking OS with growth and reproduction. The first is that traits like growth and reproduction, being metabolically demanding, lead to an increase in RS production. The second involves the diversion of resources away from self-maintenance processes (e.g. the redox system) when individuals are faced with enhanced growth or reproductive expenditure. Previous research investigating trade-offs involving growth or reproduction and self-maintenance has been equivocal. One reason for this could be that associations among redox biomarkers can vary greatly so that the biomarker selected for analysis can influence the conclusion reached about an individual’s oxidative status. Therefore the first aim of my thesis was to explore the strength and pattern of integration of five biomarkers of OS (three antioxidants, one damage and one general oxidation measure) in wild blue tit (Cyanistes caeruleus) adults and nestlings (Chapter 2). In doing so, I established that all five biomarkers should be included in future analyses, thus using this collection of biomarkers I explored my next aims; whether enhanced growth (Chapters 3 and 4) or reproductive effort (Chapter 5) can lead to increased OS levels, if these traits are traded off against self-maintenance. I accomplished these aims using both a meta-analytic and experimental approach, the latter involving manipulation of brood size in wild blue tits in order to experimentally alter growth rate of nestlings and provisioning rate (a proxy for reproductive expenditure) of adults. I also investigated the potential for redox integration to be used as an index of body condition (Chapter 2), allowing predictions about future fitness consequences of changes to oxidative state to be made. A growth – self-maintenance trade off was supported by my meta-analytic results (Chapter 4) which found OS to be a constraint on growth. However, when faced with experimentally enhanced growth, animals were typically not able to adjust this trade-off so that oxidative damage resulted. This might support the idea that energetically expensive growth causes resources to be diverted away from the redox system; however, antioxidants did not show an overall reduction in response to growth in the meta-analysis suggesting that oxidative costs of growth may result from increased RS production due to the greater metabolism needed for enhanced growth. My experimental data (Chapter 3) showed a similar pattern, with raised protein damage levels (protein carbonyls; PCs) in the fastest growing blue tit chicks in a brood, compared with their slower growing sibs. These within-brood differences in OS levels likely resulted from within-brood hierarchies and might have masked any between-brood differences, which were not observed here. Despite evidence for a growth – self-maintenance trade off, my experimental results on blue tits found no support for the hypothesis that self-maintenance is also traded off against reproduction, another energetically demanding trait. There was no link between experimentally altered reproductive expenditure and OS, nor was there a direct correlation between reproductive effort and OS (Chapter 5). However, there are various factors that likely influence whether oxidative costs are observed, including environmental conditions and whether such costs are transient. This emphasises the need for longitudinal studies following the same individuals over multiple years and across a wide range of habitats that differ in quality. This would allow investigation into how key life events interact; it might be that raised OS levels from rapid early growth have the potential to constrain reproduction or that high parental OS levels constrain offspring growth. Any oxidative costs resulting from these life-history trade-offs have the potential to impact on future fitness. Redox integration of certain biomarkers might prove to be a useful tool in making predictions about fitness, as I found in Chapter 2, as well as establishing how the redox system responds, as a whole, to changes to growth and reproduction. Finally, if the tissues measured can tolerate a given level of OS, then the level of oxidative damage might be irrelevant and not impact on future fitness at all.