929 resultados para Global History


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In this paper, we propose to study a class of neural networks with recent-history distributed delays. A sufficient condition is derived for the global exponential periodicity of the proposed neural networks, which has the advantage that it assumes neither the differentiability nor monotonicity of the activation function of each neuron nor the symmetry of the feedback matrix or delayed feedback matrix. Our criterion is shown to be valid by applying it to an illustrative system. (c) 2005 Elsevier Ltd. All rights reserved.

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Version 1 of the Global Charcoal Database is now available for regional fire history reconstructions, data exploration, hypothesis testing, and evaluation of coupled climate–vegetation–fire model simulations. The charcoal database contains over 400 radiocarbon-dated records that document changes in charcoal abundance during the Late Quaternary. The aim of this public database is to stimulate cross-disciplinary research in fire sciences targeted at an increased understanding of the controls and impacts of natural and anthropogenic fire regimes on centennial-to-orbital timescales. We describe here the data standardization techniques for comparing multiple types of sedimentary charcoal records. Version 1 of the Global Charcoal Database has been used to characterize global and regional patterns in fire activity since the last glacial maximum. Recent studies using the charcoal database have explored the relation between climate and fire during periods of rapid climate change, including evidence of fire activity during the Younger Dryas Chronozone, and during the past two millennia.

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BACKGROUND: Aloe vera supports a substantial global trade yet its wild origins, and explanations for its popularity over 500 related Aloe species in one of the world's largest succulent groups, have remained uncertain. We developed an explicit phylogenetic framework to explore links between the rich traditions of medicinal use and leaf succulence in aloes. RESULTS: The phylogenetic hypothesis clarifies the origins of Aloe vera to the Arabian Peninsula at the northernmost limits of the range for aloes. The genus Aloe originated in southern Africa ~16 million years ago and underwent two major radiations driven by different speciation processes, giving rise to the extraordinary diversity known today. Large, succulent leaves typical of medicinal aloes arose during the most recent diversification ~10 million years ago and are strongly correlated to the phylogeny and to the likelihood of a species being used for medicine. A significant, albeit weak, phylogenetic signal is evident in the medicinal uses of aloes, suggesting that the properties for which they are valued do not occur randomly across the branches of the phylogenetic tree. CONCLUSIONS: Phylogenetic investigation of plant use and leaf succulence among aloes has yielded new explanations for the extraordinary market dominance of Aloe vera. The industry preference for Aloe vera appears to be due to its proximity to important historic trade routes, and early introduction to trade and cultivation. Well-developed succulent leaf mesophyll tissue, an adaptive feature that likely contributed to the ecological success of the genus Aloe, is the main predictor for medicinal use among Aloe species, whereas evolutionary loss of succulence tends to be associated with losses of medicinal use. Phylogenetic analyses of plant use offer potential to understand patterns in the value of global plant diversity.

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Hinduism Today is a quarterly magazine that appears in roughly 15.000 copies, shipped to nearly 60 countries worldwide. The majority of readers are Hindus in diverse diaspora countries, mainly Singapur, Malaysia, Mauritius, Trinidad und the USA. Its editors are monks of Kauai Adheenam, belonging to the Śaiva Siddhānta Church, situated in Kauai, Hawai’i, USA. One of the magazine’s declared goals is to foster global Hindu solidarity and educate Hindus worldwide about their religion. In this paper, I want to take a look at the history of this magazine in connection with the Śaiva Siddhānta Church, and at the development of the expressed aims behind its publication. For this, I draw on fieldwork done in Kauai in January, 2014. After a brief introduction to some theoretical and methodological preliminaries of my work, I shall, give an overview of the history of the Śaiva Siddhānta Church, founded by Satguru Sivaya Subramuniyaswami. Following this, I will deal in more detail with the origins and development of the magazine and the websites connected with it. I will focus especially on the role the magazine was intended to play for global Hindu diasporas. A fourth chapter will analyze the modes of definition employed in order to depict Hinduism as a unified global religion. In conclusion, I shall briefly reflect upon the specific agenda of “Global Hinduism” and the strategies of positioning as followed by the publishers of Hinduism Today.

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Mycobacterium tuberculosis strains of the Beijing lineage are globally distributed and are associated with the massive spread of multidrug-resistant (MDR) tuberculosis in Eurasia. Here we reconstructed the biogeographical structure and evolutionary history of this lineage by genetic analysis of 4,987 isolates from 99 countries and whole-genome sequencing of 110 representative isolates. We show that this lineage initially originated in the Far East, from where it radiated worldwide in several waves. We detected successive increases in population size for this pathogen over the last 200 years, practically coinciding with the Industrial Revolution, the First World War and HIV epidemics. Two MDR clones of this lineage started to spread throughout central Asia and Russia concomitantly with the collapse of the public health system in the former Soviet Union. Mutations identified in genes putatively under positive selection and associated with virulence might have favored the expansion of the most successful branches of the lineage.

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William J. Hausman, Peter Hertner, and Mira Wilkins. Global Electrification: Multinational Enterprise and International Finance in the History of Light and Power, 1878–2007. New York: Cambridge University Press, 2008. xxiv + 487 pp. ISBN 978-0-521-88035-0, $80 (hardcover).

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Major global changes are placing new demands on the Australian education system. Recent statements by the Prime Minister, together with current education policy and national curriculum documents available in the public domain, look to education’s role in promoting economic prosperity and social cohesion. Collectively, they emphasise the need to equip young Australians with the knowledge, understandings and skills required to compete in the global economy and participate as engaged citizens in a culturally diverse world. However, the decision to prioritise discipline-based learning in the forthcoming Australian history curriculum without specifically encompassing culture as a referent, raises the following question. How will students acquire the cultural knowledge, understandings and skills necessary for this process? This paper addresses this question by situating the current push for a national history curriculum, with specific reference to the study of Indigenous history and the study of Asia in Australia.