241 research outputs found
Economic Diversification Supported the Growth of Mongolia’s Nomadic Empires
Populations in Mongolia from the late second millennium B.C.E. through the Mongol Empire are traditionally assumed, by archaeologists and historians, to have maintained a highly specialized horse-facilitated form of mobile pastoralism. Until recently, a dearth of direct evidence for prehistoric human diet and subsistence economies in Mongolia has rendered systematic testing of this view impossible. Here, we present stable carbon and nitrogen isotope measurements of human bone collagen, and stable carbon isotope analysis of human enamel bioapatite, from 137 well-dated ancient Mongolian individuals spanning the period c. 4400 B.C.E. to 1300 C.E. Our results demonstrate an increase in consumption of C4 plants beginning at c. 800 B.C.E., almost certainly indicative of millet consumption, an interpretation supported by archaeological evidence. The escalating scale of millet consumption on the eastern Eurasian steppe over time, and an expansion of isotopic niche widths, indicate that historic Mongolian empires were supported by a diversification of economic strategies rather than uniform, specialized pastoralism
Exotic foods reveal contact between South Asia and the Near East during the second millennium BCE
Aunque el papel clave del comercio a larga distancia en la transformaciĂłn de las cocinas en todo el mundo está bien documentado desde al menos la Ă©poca romana, la prehistoria del comercio de alimentos euroasiático es menos visible. Con el fin de arrojar luz sobre la transformaciĂłn de las cocinas del Mediterráneo oriental durante la Edad del Bronce y la Edad del Hierro Temprana, analizamos los microrestos y las proteĂnas conservadas en el cálculo dental de individuos que vivieron durante el segundo milenio a. Nuestros resultados proporcionan evidencia clara del consumo de alimentos básicos esperados, como cereales (Triticeae), sĂ©samo ( Sesamum ) y dátiles ( Phoenix ). Además, informamos evidencia del consumo de soja ( glicina ), probable banano ( Musa ) y cĂşrcuma (Curcuma ), que hace retroceder la evidencia más antigua de estos alimentos en el Mediterráneo por siglos (cĂşrcuma) o incluso milenios (soja). Descubrimos que, desde principios del segundo milenio en adelante, al menos algunas personas en el Mediterráneo oriental tuvieron acceso a alimentos de lugares distantes, incluido el sur de Asia, y esos productos probablemente se consumieron en forma de aceites, frutos secos y especias. Estos conocimientos nos obligan a repensar la complejidad y la intensidad del comercio indo-mediterráneo durante la Edad del Bronce, asĂ como el grado de globalizaciĂłn en la cocina del Mediterráneo oriental temprano. Although the key role of long-distance trade in the transformation of cuisines worldwide has been well-documented since at least the Roman era, the prehistory of the Eurasian food trade is less visible. In order to shed light on the transformation of Eastern Mediterranean cuisines during the Bronze Age and Early Iron Age, we analyzed microremains and proteins preserved in the dental calculus of individuals who lived during the second millennium BCE in the Southern Levant. Our results provide clear evidence for the consumption of expected staple foods, such as cereals (Triticeae), sesame (Sesamum), and dates (Phoenix). We additionally report evidence for the consumption of soybean (Glycine), probable banana (Musa), and turmeric (Curcuma), which pushes back the earliest evidence of these foods in the Mediterranean by centuries (turmeric) or even millennia (soybean). We find that, from the early second millennium onwards, at least some people in the Eastern Mediterranean had access to food from distant locations, including South Asia, and such goods were likely consumed as oils, dried fruits, and spices. These insights force us to rethink the complexity and intensity of Indo-Mediterranean trade during the Bronze Age as well as the degree of globalization in early Eastern Mediterranean cuisine
Nature of the electronic transitions in thiacarbocyanines with a long polymethine chain
Abstract A detailed experimental investigation and quantum-chemical analysis of symmetric cyanines of different conjugation lengths have been performed with the goal of understanding the nature of the electronic transitions in molecules that possess a long chromophore. The nature of electronic transitions in cyanines with a relatively short chromophore (inside the cyanine limit) has already been investigated and many properties of these molecules are well understood. However, little is known about the nature of the transitions beyond the cyanine limit. Their unusual properties, which were proposed by Tolbert and Zhao to be connected with symmetry breaking, still remain unexplored. The analysis of the spectral data in various solvents and results of femtosecond pumpprobe saturable absorption measurements enable us to conclude that an increase in the length of the chain leads to a symmetry breaking and the appearance of two forms with symmetrical and asymmetrical distributions of the charge density in the ground state. For thiacarbocyanines, symmetry breaking is predicted and observed for a pentacarbocyanine dye. Quantum-chemical calculations provide additional proof of this hypothesis. The excited-state absorption properties of a pentacarbocyanine in the visible region are also reported. For the first time we have observed an excited-state cross-section that is larger (%3·) than the ground state cross-section at the peak spectral position
Unique Features of a Global Human Ectoparasite Identified Through Sequencing of the Bed Bug Genome
The bed bug, Cimex lectularius, has re-established itself as a ubiquitous human ectoparasite throughout much of the world during the past two decades. This global resurgence is likely linked to increased international travel and commerce in addition to widespread insecticide resistance. Analyses of the C. lectularius sequenced genome (650 Mb) and 14,220 predicted protein-coding genes provide a comprehensive representation of genes that are linked to traumatic insemination, a reduced chemosensory repertoire of genes related to obligate hematophagy, host-symbiont interactions, and several mechanisms of insecticide resistance. In addition, we document the presence of multiple putative lateral gene transfer events. Genome sequencing and annotation establish a solid foundation for future research on mechanisms of insecticide resistance, human-bed bug and symbiont-bed bug associations, and unique features of bed bug biology that contribute to the unprecedented success of C. lectularius as a human ectoparasite
Integrative omics to detect bacteremia in patients with febrile neutropenia
Background: Cancer chemotherapy-associated febrile neutropenia (FN) is a common condition that is deadly when bacteremia is present. Detection of bacteremia depends on culture, which takes days, and no accurate predictive tools applicable to the initial evaluation are available. We utilized metabolomics and transcriptomics to develop multivariable predictors of bacteremia among FN patients. Methods: We classified emergency department patients with FN and no apparent infection at presentation as bacteremic (cases) or not (controls), according to blood culture results. We assessed relative metabolite abundance in plasma, and relative expression of 2,560 immunology and cancer-related genes in whole blood. We used logistic regression to identify multivariable predictors of bacteremia, and report test characteristics of the derived predictors. Results: For metabolomics, 14 bacteremic cases and 25 non-bacteremic controls were available for analysis; for transcriptomics we had 7 and 22 respectively. A 5-predictor metabolomic model had an area under the receiver operating characteristic curve of 0.991 (95%CI: 0.972,1.000), 100% sensitivity, and 96% specificity for identifying bacteremia. Pregnenolone steroids were more abundant in cases and carnitine metabolites were more abundant in controls. A 3-predictor gene expression model had corresponding results of 0.961 (95%CI: 0.896,1.000), 100%, and 86%. Genes involved in innate immunity were differentially expressed. Conclusions: Classifiers derived from metabolomic and gene expression data hold promise as objective and accurate predictors of bacteremia among FN patients without apparent infection at presentation, and can provide insights into the underlying biology. Our findings should be considered illustrative, but may lay the groundwork for future biomarker development
Dairy pastoralism sustained eastern Eurasian steppe populations for 5,000 years
Dairy pastoralism is integral to contemporary and past lifeways on the eastern Eurasian steppe, facilitating survival in agriculturally challenging environments. While previous research has indicated that ruminant dairy pastoralism was practiced in the region by circa 1300 BC, the origin, extent and diversity of this custom remain poorly understood. Here, we analyse ancient proteins from human dental calculus recovered from geographically diverse locations across Mongolia and spanning 5,000 years. We present the earliest evidence for dairy consumption on the eastern Eurasian steppe by circa 3000 BC and the later emergence of horse milking at circa 1200 BC, concurrent with the first evidence for horse riding. We argue that ruminant dairying contributed to the demographic success of Bronze Age Mongolian populations and that the origins of traditional horse dairy products in eastern Eurasia are closely tied to the regional emergence of mounted herding societies during the late second millennium BC
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Economic Diversification Supported the Growth of Mongolia’s Nomadic Empires
Populations in Mongolia from the late second millennium B.C.E. through the Mongol Empire are traditionally assumed, by archaeologists and historians, to have maintained a highly specialized horse-facilitated form of mobile pastoralism. Until recently, a dearth of direct evidence for prehistoric human diet and subsistence economies in Mongolia has rendered systematic testing of this view impossible. Here, we present stable carbon and nitrogen isotope measurements of human bone collagen, and stable carbon isotope analysis of human enamel bioapatite, from 137 well-dated ancient Mongolian individuals spanning the period c. 4400 B.C.E. to 1300 C.E. Our results demonstrate an increase in consumption of C4 plants beginning at c. 800 B.C.E., almost certainly indicative of millet consumption, an interpretation supported by archaeological evidence. The escalating scale of millet consumption on the eastern Eurasian steppe over time, and an expansion of isotopic niche widths, indicate that historic Mongolian empires were supported by a diversification of economic strategies rather than uniform, specialized pastoralism.
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Unique features of a global human ectoparasite identified through sequencing of the bed bug genome
The bed bug, Cimex lectularius, has re-established itself as a ubiquitous
human ectoparasite throughout much of the world during the past two decades.
This global resurgence is likely linked to increased international travel and
commerce in addition to widespread insecticide resistance. Analyses of the C.
lectularius sequenced genome (650 Mb) and 14,220 predicted protein-coding
genes provide a comprehensive representation of genes that are linked to
traumatic insemination, a reduced chemosensory repertoire of genes related to
obligate hematophagy, host–symbiont interactions, and several mechanisms of
insecticide resistance. In addition, we document the presence of multiple
putative lateral gene transfer events. Genome sequencing and annotation
establish a solid foundation for future research on mechanisms of insecticide
resistance, human–bed bug and symbiont–bed bug associations, and unique
features of bed bug biology that contribute to the unprecedented success of C.
lectularius as a human ectoparasite
The 5-Choice Continuous Performance Test: Evidence for a Translational Test of Vigilance for Mice
Attentional dysfunction is related to functional disability in patients with neuropsychiatric disorders such as schizophrenia, bipolar disorder, and Alzheimer's disease. Indeed, sustained attention/vigilance is among the leading targets for new medications designed to improve cognition in schizophrenia. Although vigilance is assessed frequently using the continuous performance test (CPT) in humans, few tests specifically assess vigilance in rodents.We describe the 5-choice CPT (5C-CPT), an elaboration of the 5-choice serial reaction (5CSR) task that includes non-signal trials, thus mimicking task parameters of human CPTs that use signal and non-signal events to assess vigilance. The performances of C57BL/6J and DBA/2J mice were assessed in the 5C-CPT to determine whether this task could differentiate between strains. C57BL/6J mice were also trained in the 5CSR task and a simple reaction-time (RT) task involving only one choice (1CRT task). We hypothesized that: 1) C57BL/6J performance would be superior to DBA/2J mice in the 5C-CPT as measured by the sensitivity index measure from signal detection theory; 2) a vigilance decrement would be observed in both strains; and 3) RTs would increase across tasks with increased attentional load (1CRT task<5CSR task<5C-CPT).C57BL/6J mice exhibited superior SI levels compared to DBA/2J mice, but with no difference in accuracy. A vigilance decrement was observed in both strains, which was more pronounced in DBA/2J mice and unaffected by response bias. Finally, we observed increased RTs with increased attentional load, such that 1CRT task<5CSR task<5C-CPT, consistent with human performance in simple RT, choice RT, and CPT tasks. Thus we have demonstrated construct validity for the 5C-CPT as a measure of vigilance that is analogous to human CPT studies
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