649 research outputs found
Life and death at precolumbian Lavoutte, Saint Lucia, Lesser Antilles
The Caribbean archaeological record requires immediate attention and protection. Development and natural forces have impacted archaeological sites, destroying or severely damaging them. The precolumbian site of Lavoutte, located in northern Saint Lucia, has been known as a major Late Ceramic Age (A.D. 1000–1500) settlement since the 1960s, but it has been damaged over the past decades by both natural and human processes. Multidisciplinary field and laboratory methodologies were implemented during a rescue project at the site from 2009 to 2010. This paper presents the results of collaborative efforts between local and international organizations. The first goal was to demonstrate the importance of protection and rescue of endangered archaeological sites. Secondly, we aimed to show that by adopting a
multidisciplinary approach including artifact analysis, bioarchaeology, paleoenvironmental reconstruction, and geochemistry, severely damaged sites can be of significant informational value. Archaeology of indigenous Americ
Thermal instability in ionized plasma
We study magnetothermal instability in the ionized plasmas including the
effects of Ohmic, ambipolar and Hall diffusion. Magnetic field in the single
fluid approximation does not allow transverse thermal condensations, however,
non-ideal effects highly diminish the stabilizing role of the magnetic field in
thermally unstable plasmas. Therefore, enhanced growth rate of thermal
condensation modes in the presence of the diffusion mechanisms speed up the
rate of structure formation.Comment: Accepted for publication in Astrophysics & Space Scienc
Anse Trabaud commune de Sainte-Anne, Martinique:reconstruction d’un village amérindien. Son insertion dans le réseau d’échanges Antillais entre 600 et 1200 après J.-C. Rapport final, prospection thématique, sondages et fouille 2012 et 2015.
Archaeology of indigenous Americ
Mangrove archives: unravelling human-environment interactions from deeply buried deposits at the site Anse Trabaud, Martinique, Lesser Antilles (1290–780 cal BP)
The site of Anse Trabaud on Martinique in the Windward Islands of the Lesser Antilles has yielded valuable information about human occupation from deep beneath its surface. The site is located in the southeastern part of the island, an area vulnerable to extreme wave events. The archaeological deposits are dated to 1290–780 cal BP (2σ). The earliest horizon is buried under thick layers of mangrove sediments. The deeply buried deposits have allowed excellent preservation of inorganic and organic remains providing an unexpected opportunity to reconstruct the paleoenvironmental conditions of past human settlement, and to study human-environment interactions and social adaptation to climate challenges in this part of the Caribbean archipelago. The cultural remains provide invaluable information into the exploitation of the surroundings of the site as well as into the subsistence patterns, material culture repertoires, procurement strategies and use and exchange of raw materials and tools. Additionally, the excellent preservation of organic materials offers new insights into food plants grown and harvested on-site, and then processed and consumed. The environmental challenges incited the Anse Trabaud community to adapt their settlement organisation and procurement strategies over time and underscore the importance of their participation in a regional and social network of mobility and exchange.Seventh Framework Programme (FP7)319209Bioarchaeolog
Neonatal intervention
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68335/2/10.1177_027112148300300105.pd
From early markers to neuro-developmental mechanisms of autism
A fast growing field, the study of infants at risk because of having an older sibling with autism (i.e. infant sibs) aims to identify the earliest signs of this disorder, which would allow for earlier diagnosis and intervention. More importantly, we argue, these studies offer the opportunity to validate existing neuro-developmental models of autism against experimental evidence. Although autism is mainly seen as a disorder of social interaction and communication, emerging early markers do not exclusively reflect impairments of the “social brain”. Evidence for atypical development of sensory and attentional systems highlight the need to move away from localized deficits to models suggesting brain-wide involvement in autism pathology. We discuss the implications infant sibs findings have for future work into the biology of autism and the development of interventions
Comparison of deep inelastic electron-photon scattering data with the HERWIG and PHOJET Monte Carlo models
Deep inelastic electron-photon scattering is studied in the range from 1.2 to 30 GeV using the LEP1 data taken with the ALEPH, L3 and OPAL detectors at centre-of-mass energies close to the mass of the Z boson. Distributions of the measured hadronic final state are corrected to the hadron level and compared to the predictions of the HERWIG and PHOJET Monte Carlo models. For large regions in most of the distributions studied the results of the different experiments agree with one another. However, significant differences are found between the data and the models. Therefore the combined LEP data serve as an important input to improve on the Monte Carlo models.Deep inelastic electron-photon scattering is studied in the Q**2 range from 1.2 to 30 GeV**2 using the LEP1 data taken with the ALEPH, L3 and OPAL detectors at centre-of-mass energies close to the mass of the Z boson. Distributions of the measured hadronic final state are corrected to the hadron level and compared to the predictions of the HERWIG and PHOJET Monte Carlo models. For large regions in most of the distributions studied the results of the different experiments agree with one another. However, significant differences are found between the data and the models. Therefore the combined LEP data serve as an important input to improve on the Monte Carlo models
A palaeoenvironmental reconstruction (based on palaeobotanical data and diatoms) of the Middle Pleistocene elephant (Palaeoloxodon antiquus) butchery site at Marathousa, Megalopolis, Greece
Bioarchaeolog
Non Linear Current Response of a Many-Level Tunneling System: Higher Harmonics Generation
The fully nonlinear response of a many-level tunneling system to a strong
alternating field of high frequency is studied in terms of the
Schwinger-Keldysh nonequilibrium Green functions. The nonlinear time dependent
tunneling current is calculated exactly and its resonance structure is
elucidated. In particular, it is shown that under certain reasonable conditions
on the physical parameters, the Fourier component is sharply peaked at
, where is the spacing between
two levels. This frequency multiplication results from the highly nonlinear
process of photon absorption (or emission) by the tunneling system. It is
also conjectured that this effect (which so far is studied mainly in the
context of nonlinear optics) might be experimentally feasible.Comment: 28 pages, LaTex, 7 figures are available upon request from
[email protected], submitted to Phys.Rev.
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