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Distinct Episodes (distinct + episode)
Selected AbstractsDating the introduction of cereal cultivation to the British Isles: early palaeoecological evidence from the Isle of ManJOURNAL OF QUATERNARY SCIENCE, Issue 7 2003James B. Innes Abstract The adoption of cereal cultivation is a key benchmark in the transition from Mesolithic hunter,gatherer foraging to Neolithic farming economies, but the nature, timing and ecological,cultural context of the earliest cereal use in the British Isles and northwest Europe is still uncertain. We present AMS radiocarbon dating and fine-resolution pollen evidence from the Isle of Man for cereal growing in the latter stages of a distinct episode of forest disturbance at almost 6000,yr,BP (uncalibrated). The coherent ecological structure of this phase at the fine resolution level suggests that it records cereal cultivation well before the Ulmus decline, rather than wild grass pollen grains. This example is one of a cluster of early dates for cereal-type pollen near the start of the sixth millenium BP, including several around the Irish Sea, which indicate that the introduction of cereal agriculture probably occurred as early in the central British Isles as in the northern European plain. This early cereal phase is followed later by a probable phase of pre- Ulmus decline pastoral activity. We also report Mesolithic age woodland disturbance around 7000,yr,BP (uncalibrated) and the first radiocarbon dates for mid-Holocene forest history of the Isle of Man. Copyright © 2003 John Wiley & Sons, Ltd. [source] Geochronology, sediment provenance, and fossil emplacement at Sumidouro Cave, a classic late Pleistocene/early Holocene Paleoanthropological site in eastern BrazilGEOARCHAEOLOGY: AN INTERNATIONAL JOURNAL, Issue 8 2005Luís B. Piló Peter Wilhelm Lund's (1845a) heavily debated suggestion of a contemporaneity between Paleo-Indians and extinct Pleistocene fauna at Sumidouro Cave was re-examined through detailed sedimentological and geochronological analyses of sediment and both human and faunal remains. Sources of the cave's sediment include both entrances as well as ceiling fissures. Non-human fossils, on the other hand, were probably carried by floodwater through the once more-spacious swallet entrance. Seasonal flooding reworked and mixed these two highly asynchronous assemblages. U-series and radiocarbon ages indicate that there are at least two distinct episodes of sediment input in the cave, at ,240,000 yr B.P. and ,8000 yr B.P. Human remains represent a later emplacement event, probably at ,8400 cal yr B.P. Although the human remains are of considerable age, the cave's complex stratigraphy, flooding dynamics, and extensive removal of the cave's filling during earlier excavations do not allow the determination of an unequivocal co-existence between Paleo-Indians and extinct megafauna at the site. © 2005 Wiley Periodicals, Inc. [source] The changing face of mass murder: massacre, genocide, and postgenocideINTERNATIONAL SOCIAL SCIENCE JOURNAL, Issue 174 2002Mark Levene This contribution argues the case for the efficacy of labelling distinct episodes of extreme violence. While accepting common ingredients in what are here denoted as examples of ,massacre', ,genocide', and ,post-genocide the clue to their ' separateness lies not in the form but in the historical framework within which each occurs. Only by examining patterns of historical process, in this case in the late-Ottoman empire, are we likely to be able to build a broader analysis of the nature and causation of chronic and systemic violence in the modern world. [source] Synchronous peak Barrovian metamorphism driven by syn-orogenic magmatism and fluid flow in southern Connecticut, USAJOURNAL OF METAMORPHIC GEOLOGY, Issue 5 2008P. J. LANCASTER Abstract Recent work in Barrovian metamorphic terranes has found that rocks experience peak metamorphic temperatures across several grades at similar times. This result is inconsistent with most geodynamic models of crustal over-thickening and conductive heating, wherein rocks which reach different metamorphic grades generally reach peak temperatures at different times. Instead, the presence of additional sources of heat and/or focusing mechanisms for heat transport, such as magmatic intrusions and/or advection by metamorphic fluids, may have contributed to the contemporaneous development of several different metamorphic zones. Here, we test the hypothesis of temporally focussed heating for the Wepawaug Schist, a Barrovian terrane in Connecticut, USA, using Sm,Nd ages of prograde garnet growth and U,Pb zircon crystallization ages of associated igneous rocks. Peak temperature in the biotite,garnet zone was dated (via Sm,Nd on garnet) at 378.9 ± 1.6 Ma (2,), whereas peak temperature in the highest grade staurolite,kyanite zone was dated (via Sm,Nd on garnet rims) at 379.9 ± 6.8 Ma (2,). These garnet ages suggest that peak metamorphism was pene-contemporaneous (within error) across these metamorphic grades. Ion microprobe U,Pb ages for zircon from igneous rocks hosted by the metapelites also indicate a period of syn-metamorphic peak igneous activity at 380.6 ± 4.7 Ma (2,), indistinguishable from the peak ages recorded by garnet. A 388.6 ± 2.1 Ma (2,) garnet core age from the staurolite,kyanite zone indicates an earlier episode of growth (coincident with ages from texturally early zircon and a previously published monazite age) along the prograde regional metamorphic T,t path. The timing of peak metamorphism and igneous activity, as well as the occurrence of extensive syn-metamorphic quartz vein systems and pegmatites, best supports the hypothesis that advective heating driven by magmas and fluids focussed major mineral growth into two distinct episodes: the first at c. 389 Ma, and the second, corresponding to the regionally synchronous peak metamorphism, at c. 380 Ma. [source] Integrons as tools for epidemiological studiesCLINICAL MICROBIOLOGY AND INFECTION, Issue 2 2004P. Severino Abstract The integron content of Gram-negative strains implicated in three distinct episodes of suspected cross-infection among inpatients was investigated and compared with ribotyping. In the first episode, ribotyping identified a strain of Acinetobacter, isolated over a 3-month period, responsible for an outbreak associated with the use of mechanical ventilation in the intensive care unit (ICU). The second episode concerned simultaneous isolations of Pseudomonas aeruginosa and Serratia marcescens from 13 bronchoscopy patients. In these two episodes, results obtained by analysis of integron content and ribotyping were in agreement and correctly identified the epidemiologically related strains. In the third episode, isolates of Enterobacter cloacae were collected from patients in the neonatal ICU over a 3-month period. Although several isolates belonged to the same ribotype, cross-infection could not always be confirmed when the integron content was analysed. Integron detection can be considered a useful tool for studying molecular epidemiology in hospital environments, facilitating the quick detection of possible cross-infection cases, especially in critical wards such as the ICU. [source] | |||||||||||||