ABSTRACT
Explaining the factors that influence past dietary variation is critically important for understanding changes in subsistence, health, and status in past societies; yet systematic studies comparing possible driving factors remain scarce. Here we compile the largest dataset of past diet derived from stable isotope δ13C and δ15N values in the Americas to quantitatively evaluate the impact of 7000 years of climatic and demographic change on dietary variation in the Central Andes. Specifically, we couple paleoclimatic data from a general circulation model with estimates of relative past population inferred from archaeologically derived radiocarbon dates to assess the influence of climate and population on spatiotemporal dietary variation using an ensemble machine learning model capable of accounting for interactions among predictors. Results reveal that climate and population strongly predict diet (80% of δ15N and 66% of δ13C) and that Central Andean diets correlate much more strongly with local climatic conditions than regional population size, indicating that the past 7000 years of dietary change was influenced more by climatic than socio-demographic processes. Visually, the temporal pattern suggests decreasing dietary variation across elevation zones during the Late Horizon, raising the possibility that sociopolitical factors overrode the influence of local climatic conditions on diet during that time. The overall findings and approach establish a general framework for understanding the influence of local climate and demography on dietary change across human history.
ABSTRACT
We present evidence of Middle Pleistocene activity in the central Aegean Basin at the chert extraction and reduction complex of Stelida (Naxos, Greece). Luminescence dating places ~9000 artifacts in a stratigraphic sequence from ~13 to 200 thousand years ago (ka ago). These artifacts include Mousterian products, which arguably provide first evidence for Neanderthals in the region. This dated material attests to a much earlier history of regional exploration than previously believed, opening the possibility of alternative routes into Southeast Europe from Anatolia (and Africa) for (i) hominins, potentially during sea level lowstands (e.g., Marine Isotope Stage 8) permitting terrestrial crossings across the Aegean, and (ii) Homo sapiens of the Early Upper Paleolithic (Aurignacian), conceivably by sea.
Subject(s)
Hominidae/genetics , Africa , Animals , Europe , Fossils , Greece , Neanderthals , OccupationsABSTRACT
BACKGROUND: Moyamoya disease (MMD) is a rare cerebrovascular condition, often presenting as a headache or stroke in adults. Anesthetic management of this illness may challenge providers because it can affect the long-term neurologic outcome and hospital length of stay (LOS) in patients with MMD. MATERIALS AND METHODS: A literature search was conducted to assess etiology and epidemiology, as well as existing reports of intraoperative management of MMD. Due to sparse findings, the search was expanded to include studies of the use of intraoperative anesthetic agents during other neurosurgical procedures. We also retrospectively reviewed all MMD cases from January 1, 2009, to December 31, 2015, at Memorial Hermann Hospital-Texas Medical Center, where intraoperative management involved craniotomy and surgical revascularization. Data were collected primarily on the use of several anesthetic agents. The LOS and any adverse events were also recorded for each case. The data were divided into two equivalent case cohorts: (1) January 1, 2009, to February 18, 2013, and (2) February 19, 2013, to December 31, 2015. RESULTS: Remifentanil use notably increased between the first and second time periods while fentanyl use decreased. Desflurane usage also demonstrated an observed increase when our two cohorts were compared. Additionally, there was a decrease in the mean LOS between the first and second periods of 3.9 and 3.3 days, respectively. CONCLUSION: Increasing use of remifentanil in MMD cases could be attributed to its ability to provide more stable hemodynamics during induction, maintenance, and emergence of anesthesia when compared with fentanyl. Lower systolic pressures, diastolic pressures, and heart rates were reported in patients receiving remifentanil over fentanyl.
Subject(s)
Anesthesia/methods , Cerebral Revascularization/methods , Craniotomy/methods , Moyamoya Disease/surgery , Hemodynamics , Humans , Retrospective Studies , Treatment OutcomeABSTRACT
Holocene climate variability in the Mediterranean Basin is often cited as a potential driver of societal change, but the mechanisms of this putative influence are generally little explored. In this paper we integrate two tools-agro-ecosystem modeling of potential agricultural yields and spatial analysis of archaeological settlement pattern data-in order to examine the human consequences of past climatic changes. Focusing on a case study in Provence (France), we adapt an agro-ecosystem model to the modeling of potential agricultural productivity during the Holocene. Calibrating this model for past crops and agricultural practices and using a downscaling approach to produce high spatiotemporal resolution paleoclimate data from a Mediterranean Holocene climate reconstruction, we estimate realistic potential agricultural yields under past climatic conditions. These serve as the basis for spatial analysis of archaeological settlement patterns, in which we examine the changing relationship over time between agricultural productivity and settlement location. Using potential agricultural productivity (PAgP) as a measure of the human consequences of climate changes, we focus on the relative magnitudes of 1) climate-driven shifts in PAgP and 2) the potential increases in productivity realizable through agricultural intensification. Together these offer a means of assessing the scale and mechanisms of the vulnerability and resilience of Holocene inhabitants of Provence to climate change. Our results suggest that settlement patterns were closely tied to PAgP throughout most of the Holocene, with the notable exception of the period from the Middle Bronze Age through the Early Iron Age. This pattern does not appear to be linked to any climatically-driven changes in PAgP, and conversely the most salient changes in PAgP during the Holocene cannot be clearly linked to any changes in settlement pattern. We argue that this constitutes evidence that vulnerability and resilience to climate change are strongly dependent on societal variables.