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- Heckbert, Scott, et al.
(författare)
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Growing the Precolumbian Maya Social-Ecological System from the Bottom Up
- 2019
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Ingår i: The Oxford Handbook of Historical Ecology and Applied Archaeology / edited by Christian Isendahl and Daryl Stump.. - Oxford : Oxford University Press. - 9780199672691 ; , s. 302-322
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Bokkapitel (refereegranskat)abstract
- Archaeological data can be represented in quantitative models to test theories of societal growth, development, and resilience. This chapter describes the results of simulations employing integrated agent-based, cellular automata, and network models to represent elements of the ancient Maya social-ecological system. The purpose of the model is to better understand the complex dynamics of the Maya civilization and to test quantitative indicators of resilience as predictors of system sustainability or decline. The model examines the relationship between population growth, agricultural production, pressure on ecosystem services, forest succession, value of trade, and the stability of trade networks. These combine to allow agents representing Maya settlements to develop and expand within a landscape that changes under climate variation and responds to anthropogenic pressure. The model is able to reproduce spatial patterns and timelines somewhat analogous to that of the ancient Maya, although this model requires refinement and further archaeological data for calibration.
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| 3. |
- Stephens, Lucas, et al.
(författare)
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Archaeological assessment reveals Earth’s early transformation through land use
- 2019
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Ingår i: Science. - : American Association for the Advancement of Science. - 0036-8075 .- 1095-9203. ; 365:6456, s. 897-902
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Tidskriftsartikel (refereegranskat)abstract
- Humans began to leave lasting impacts on Earth’s surface starting 10,000 to 8000 years ago. Through a synthetic collaboration with archaeologists around the globe, Stephens et al. compiled a comprehensive picture of the trajectory of human land use worldwide during the Holocene (see the Perspective by Roberts). Hunter-gatherers, farmers, and pastoralists transformed the face of Earth earlier and to a greater extent than has been widely appreciated, a transformation that was essentially global by 3000 years before the present.Science, this issue p. 897; see also p. 865Environmentally transformative human use of land accelerated with the emergence of agriculture, but the extent, trajectory, and implications of these early changes are not well understood. An empirical global assessment of land use from 10,000 years before the present (yr B.P.) to 1850 CE reveals a planet largely transformed by hunter-gatherers, farmers, and pastoralists by 3000 years ago, considerably earlier than the dates in the land-use reconstructions commonly used by Earth scientists. Synthesis of knowledge contributed by more than 250 archaeologists highlighted gaps in archaeological expertise and data quality, which peaked for 2000 yr B.P. and in traditionally studied and wealthier regions. Archaeological reconstruction of global land-use history illuminates the deep roots of Earth’s transformation and challenges the emerging Anthropocene paradigm that large-scale anthropogenic global environmental change is mostly a recent phenomenon.
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| 4. |
- Wang, Li-San, et al.
(författare)
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Rarity of the Alzheimer Disease-Protective APP A673T Variant in the United States.
- 2015
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Ingår i: JAMA neurology. - : American Medical Association (AMA). - 2168-6157 .- 2168-6149. ; 72:2
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Tidskriftsartikel (refereegranskat)abstract
- Recently, a rare variant in the amyloid precursor protein gene (APP) was described in a population from Iceland. This variant, in which alanine is replaced by threonine at position 673 (A673T), appears to protect against late-onset Alzheimer disease (AD). We evaluated the frequency of this variant in AD cases and cognitively normal controls to determine whether this variant will significantly contribute to risk assessment in individuals in the United States.
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