12 resultados para OLD-WORLD

em QUB Research Portal - Research Directory and Institutional Repository for Queen's University Belfast


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Climate model projections suggestwidespread drying in the Mediterranean Basin and wetting in Fennoscandia in the coming decades largely as a consequence of greenhouse gas forcing of climate. To place these and other “Old World” climate projections into historical perspective based on more complete estimates of natural hydroclimatic variability, we have developed the “Old World Drought Atlas” (OWDA), a set of year-to-year maps of tree-ring reconstructed summer wetness and dryness over Europe and the Mediterranean Basin during the Common Era.
The OWDA matches historical accounts of severe drought and wetness with a spatial completeness not previously available. In addition, megadroughts reconstructed over north-central Europe in the 11th and mid-15th centuries
reinforce other evidence from North America and Asia that droughts were more severe, extensive, and prolonged over Northern Hemisphere land areas before the 20th century, with an inadequate understanding of their causes. The OWDA provides new data to determine the causes of Old World drought and wetness and attribute past climate variability to forced and/or internal variability.

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In the fourteenth century the Old World witnessed a series of profound and abrupt changes in the trajectory of long-established historical trends. Trans-continental networks of exchange fractured and an era of economic contraction and demographic decline dawned from which Latin Christendom would not begin to emerge until its voyages of discovery at the end of the fifteenth century. In a major new study of this 'Great Transition', assessment is made of the contributions of commercial recession, war, climate change,and eruption of the Black Death to a far-reaching reversal of fortunes which spared no part of Eurasia. A wealth of new historical, palaeoecological and biological evidence are synthesised, including estimates of national income, reconstructions of past climates. and genetic analysis of DNA extracted from the teeth of plague victims, to provide a fresh account of the creation, collapse and realignment of western Europe's late-medieval commercial economy.

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Madagascar is home to numerous endemic species and lineages, but the processes that have contributed to its endangered diversity are still poorly understood. Evidence is accumulating to demonstrate the importance of Tertiary dispersal across varying distances of oceanic barriers, supplementing vicariance relationships dating back to the Cretaceous, but these hypotheses remain tentative in the absence of well-supported phylogenies. In the Papilio demoleus group of swallowtail butterflies, three of the five recognized species are restricted to Madagascar, whereas the remaining two species range across the Afrotropical zone and southern Asia plus Australia. We reconstructed phylogenetic relationships for all species in the P. demoleus group, as well as 11 outgroup Papilio species, using 60 morphological characters and about 4 kb of nucleotide sequences from two mitochondrial (cytochrome oxidase I and II) and two nuclear (wg and EF-1a) genes. Of the three endemic Malagasy species, the two that are formally listed as endangered or at risk represented the most basal divergences in the group, while the more common third endemic was clearly related to African P. demodocus. The fifth species, P. demoleus, showed little differentiation across southern Asia, but showed divergence from its subspecies sthenelus in Australia. Dispersal-vicariance analysis using cladograms derived from morphology and three independent genes indicated a Malagasy diversification of lime swallowtails in the middle Miocene. Thus, diversification processes on the island of Madagascar may have contributed to the origin of common butterflies that now occur throughout much of the Old World tropical and subtemperate regions. An alternative hypothesis, that Madagascar is a refuge for ancient lineages resulting from successive colonizations from Africa, is less parsimonious and does not explain the relatively low continental diversity of the group.

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The nonsteroidal anti-inflammatory drug diclofenac is extremely toxic to Old World Gyps vultures (median lethal dose -0.1-0.2 mg/kg), evoking visceral gout, renal necrosis, and mortality within a few days of exposure. Unintentional secondary poisoning of vultures that fed upon carcasses of diclofenac-treated livestock decimated populations in the Indian subcontinent. Because of the widespread use of diclofenac and other cyclooxygenase-2 inhibiting drugs, a toxicological study was undertaken in turkey vultures (Cathartes aura) as an initial step in examining sensitivity of New World scavenging birds. Two trials were conducted entailing oral gavage of diclofenac at doses ranging from 0.08 to 25 mg/kg body weight. Birds were observed for 7 d, blood samples were collected for plasma chemistry (predose and 12, 24, and 48 h and 7 d postdose), and select individuals were necropsied. Diclofenac failed to evoke overt signs of toxicity, visceral gout, renal necrosis, or elevate plasma uric acid at concentrations greater than 100 times the estimated median lethal dose reported for Gyps vultures. For turkey vultures receiving 8 or 25 mg/kg, the plasma half-life of diclofenac was estimated to be 6 h, and it was apparently cleared after several days as no residues were detectable in liver or kidney at necropsy. Differential sensitivity among avian species is a hallmark of cyclooxygenase-2 inhibitors, and despite the tolerance of turkey vultures to diclofenac, additional studies in related scavenging species seem warranted.

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Trump, D., Malone, C and Stoddart, S., ,G. Burenhult, (ed.). 1993, Harper Collins: New York. p. 100-101.

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With the advent of 'ancient DNA' studies on preserved material of extant and extinct species, museums and herbaria now represent an important although still underutilized resource in molecular ecology. The ability to obtain sequence data from archived specimens can reveal the recent history of cryptic species and introductions. We have analysed extant and herbarium samples of the highly invasive green alga Codium fragile, many over 100 years old, to identify cryptic accessions of the invasive strain known as C. fragile ssp. tomentosoides, which can be identified by a unique haplotype. Molecular characterization of specimens previously identified as native in various regions shows that the invasive tomentosoides strain has been colonizing new habitats across the world for longer than records indicate, in some cases nearly 100 years before it was noticed. It can now be found in the ranges of all the other native haplotypes detected, several of which correspond to recognized subspecies. Within regions in the southern hemisphere there was a greater diversity of haplotypes than in the northern hemisphere, probably as a result of dispersal by the Antarctic Circumpolar Current. The findings of this study highlight the importance of herbaria in preserving contemporaneous records of invasions as they occur, especially when invasive taxa are cryptic.

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Throughout his writing life, Robert Graves was consistently and often publicly hostile to the work of W.B. Yeats, whilst still also owing a considerable debt to the older poet (who he never met). This essay explores Graves' complex responses to Yeats, arguing that his antagonism may be understood in the light of his own Anglo-Irish background, and is implicated in his relations with his father, Alfred Perceval Graves, as well as his experience of the First World War. Probing the suggestiveness of Graves's claim in 1959 that his poems 'remain true to the Anglo-Irish poetic tradition into which I was born', it traces the relation between Yeats and Graves through correspondence, critical writings, and through a comparative reading of Yeats's A Vision and Graves's The White Goddess, and reveals underlying similarities in their critical and mythological thinking in spite of Graves's public disavowal of the Yeatsian aesthetic.

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Despite its benefits, co-ownership of land creates problems where relations between the parties
have soured, or one person simply wants to extricate themselves from this arrangement. The
remedies of compulsory partition and sale allow one joint tenant or tenant in common to terminate
co-ownership against the wishes of the others, by seeking a court order to this effect. Throughout
parts of the common law world, this has be en based on nineteenth century English legislation namely
the Partition Act 1868, the key elements of which remain in force in Western Australia,
South Australia, Tasmania and the Australian Capital Territory. This article provides an up-to-date
analysis of the law on compulsory partition and sale as derived from the 1868 Act and analogous
provisions, drawing not only on Australian cases, but on frequently overlooked decisions from
courts in both parts of Ireland and in parts of Canada, as well as ‘old’ English judgments on the
1868 Act.

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We find that regional height levels around the world were fairly uniform throughout most of the 19th century, with two exceptions: above-average levels in Anglo-Saxon settlement regions and below-average levels in Southeast Asia. After 1880, substantial diver- gences began to differentiate other regions -- making the world population taller, but more unequal. During the late 19th century and 20th century, heights between world regions devi- ated significantly, when incomes also became very unequal. Interestingly, during the “breaking point period” between the two regimes, heights declined significantly in the cattle-rich New World countries, whereas they started to increase in Old Europe. We discuss in this study whether immigration was a core factor to influence the height decline in the “Anthropometric Decline of the Cowboy and Gaucho Empires”.