940 resultados para 430204 Archaeology of Complex Societies - Asia, Africa, Oceania and the Americas


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We present results of starch analysis of archaeological deposits from Pitcairn Island. High concentrations of starch grains preserved in cell membranes, and xylem tracheary elements, consistent with introduced Colocasia esculenta (taro) were found. Because of limited age control, we are uncertain if the microfossils are prehistoric. Problems associated with identifying taxa with small starch grains in extractions from weathered deposits are highlighted. (c) 2006 Elsevier Ltd. All rights reserved.

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Documenting the history of settlement in Hawaii during the last few Centuries before European contact, is crucial to charting the evolution of the most complex chiefdom in Polynesia. It is precisely this period that Hawaii. and many Polynesian Societies, Underwent their most rapid changes in political, economic and social organisation. The last similar to 500 to 300 years in the C-14 calibration curve is problematic with wide fluctuations Often rendering large age spans that do not precisely date single events, especially troubling with a culture-historical record of similar to 1000 years duration. Here we present in extremely high precision Th-230 chronology for archaeologically constrained coral samples from a range of occupancy sites. Our high precision dates allow the time of site use to be clearly demonstrated. They also provide the first dates for habitation sites in Hawaii that clearly show contemporaneous occupation-the major problem in settlement pattern archaeology. We demonstrate that two sites were occupied within the same year. Our refined chronology, provides new and exciting oppurtunities for tracking sociopolitical and economic developments during the last few centuries-the crucial period in the evolution and transformation of Polynesian societies. (c) 2005 Elsevier Ltd. All rights reserved.

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Micro-Raman spectroscopy was applied to the study of multiple layered wall paints from the Rosalila temple, Copan, Honduras, which dates to the Middle Classic period (A.D. 520 to 655). Samples of red, green and grey paint and a thick white overcoating were analysed. The paint pigments have been identified as hematite, celadonite or green earth and a combined carbon/mica mixture. By combining Raman spectroscopy with micro-ATR infrared spectroscopy and environmental scanning electron microscopy (ESEM), a detailed study has been made of the materials and processes used to make the stucco and paints. The use of green earth as a green pigment on Maya buildings has not been reported before. The combination of carbon and muscovite mica to create a reflective paint is also a novel finding.

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This paper, focusing principally on post-Lapita times, outlines the course and outcomes of work undertaken over the last two decades in the West New Britain-Vitiaz Strait-north New Guinea coastal region. It presents two principal arguments. The first is that major periods of movement and abandonment documented in the archaeological sequences of this region from about 3,500 years ago coincide with the record of volcanism in the Talasea-Cape Hoskins area. The second is that the post-Lapita sequences of this region differ significantly from the post-Lapita sequences emerging in the island arc reaching from Manus via New Ireland to southern and eastern island Melanesia, which show continuous occupation and pottery production.

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INTRODUCTION HIV care and treatment programmes worldwide are transforming as they push to deliver universal access to essential prevention, care and treatment services to persons living with HIV and their communities. The characteristics and capacity of these HIV programmes affect patient outcomes and quality of care. Despite the importance of ensuring optimal outcomes, few studies have addressed the capacity of HIV programmes to deliver comprehensive care. We sought to describe such capacity in HIV programmes in seven regions worldwide. METHODS Staff from 128 sites in 41 countries participating in the International epidemiologic Databases to Evaluate AIDS completed a site survey from 2009 to 2010, including sites in the Asia-Pacific region (n=20), Latin America and the Caribbean (n=7), North America (n=7), Central Africa (n=12), East Africa (n=51), Southern Africa (n=16) and West Africa (n=15). We computed a measure of the comprehensiveness of care based on seven World Health Organization-recommended essential HIV services. RESULTS Most sites reported serving urban (61%; region range (rr): 33-100%) and both adult and paediatric populations (77%; rr: 29-96%). Only 45% of HIV clinics that reported treating children had paediatricians on staff. As for the seven essential services, survey respondents reported that CD4+ cell count testing was available to all but one site, while tuberculosis (TB) screening and community outreach services were available in 80 and 72%, respectively. The remaining four essential services - nutritional support (82%), combination antiretroviral therapy adherence support (88%), prevention of mother-to-child transmission (PMTCT) (94%) and other prevention and clinical management services (97%) - were uniformly available. Approximately half (46%) of sites reported offering all seven services. Newer sites and sites in settings with low rankings on the UN Human Development Index (HDI), especially those in the President's Emergency Plan for AIDS Relief focus countries, tended to offer a more comprehensive array of essential services. HIV care programme characteristics and comprehensiveness varied according to the number of years the site had been in operation and the HDI of the site setting, with more recently established clinics in low-HDI settings reporting a more comprehensive array of available services. Survey respondents frequently identified contact tracing of patients, patient outreach, nutritional counselling, onsite viral load testing, universal TB screening and the provision of isoniazid preventive therapy as unavailable services. CONCLUSIONS This study serves as a baseline for on-going monitoring of the evolution of care delivery over time and lays the groundwork for evaluating HIV treatment outcomes in relation to site capacity for comprehensive care.

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"Appendix to v.I, in two parts, containing 1. The history of the voyages around the world, and toward the North and South poles, which have been made since the year 1764, by English navigators. 2. A digested and geographical account of the most considerable islands and countries which have been either discovered or explored during those voyages, collected from every writer upon those subjects".

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In the current paper, we have primarily addressed one powerful simulation tool developed during the last decades-Large Eddy Simulation (LES), which is most suitable for unsteady three-dimensional complex turbulent flows in industry and natural environment. The main point in LES is that the large-scale motion is resolved while the small-scale motion is modeled or, in geophysical terminology, parameterized. With a view to devising a subgrid-scale(SGS) model of high quality, we have highlighted analyzing physical aspects in scale interaction and-energy transfer such as dissipation, backscatter, local and non-local interaction, anisotropy and resolution requirement. They are the factors responsible for where the advantages and disadvantages in existing SGS models come from. A case study on LES of turbulence in vegetative canopy is presented to illustrate that LES model is more based on physical arguments. Then, varieties of challenging complex turbulent flows in both industry and geophysical fields in the near future-are presented. In conclusion; we may say with confidence that new century shall see the flourish in the research of turbulence with the aid of LES combined with other approaches.