20 research outputs found

    Human inbreeding has decreased in time through the Holocene

    Get PDF
    The history of human inbreeding is controversial. In particular, how the development of sedentary and/or agricultural societies may have influenced overall inbreeding levels is unclear. Here we present an approach for reliable estimation of runs of homozygosity (ROH) in genomes with ≥3x mean sequence coverage across >1 million SNPs, and apply this to 411 ancient Eurasian genomes from the last 15,000 years. We show that the frequency of inbreeding, as measured by ROH, has decreased over time. The strongest effect is associated with the Neolithic transition, but the trend has since continued, indicating a population size effect on inbreeding prevalence. We further show that most inbreeding in our historical sample can be attributed to small population size instead of consanguinity. We observed singular cases of high consanguinity only among members of farming societies

    Spatial and temporal heterogeneity in human mobility patterns in Holocene Southwest Asia and the East Mediterranean

    Get PDF
    We present a spatiotemporal picture of human genetic diversity in Anatolia, Iran, Levant, South Caucasus, and the Aegean, a broad region that experienced the earliest Neolithic transition and the emergence of complex hierarchical societies. Combining 35 new ancient shotgun genomes with 382 ancient and 23 present-day published genomes, we found that genetic diversity within each region steadily increased through the Holocene. We further observed that the inferred sources of gene flow shifted in time. In the first half of the Holocene, Southwest Asian and the East Mediterranean populations homogenized among themselves. Starting with the Bronze Age, however, regional populations diverged from each other, most likely driven by gene flow from external sources, which we term “the expanding mobility model.” Interestingly, this increase in inter-regional divergence can be captured by outgroup-f3_3-based genetic distances, but not by the commonly used FST_{ST} statistic, due to the sensitivity of FST_{ST}, but not outgroup-f3_3, to within-population diversity. Finally, we report a temporal trend of increasing male bias in admixture events through the Holocene

    Archaeogenetic analysis of Neolithic sheep from Anatolia suggests a complex demographic history since domestication

    Get PDF
    Yurtman, ozer, Yuncu et al. provide an ancient DNA data set to demonstrate the impact of human activity on the demographic history of domestic sheep. The authors demonstrate that there may have been multiple domestication events with notable changes to the gene pool of European and Anatolian sheep since the Neolithic. Sheep were among the first domesticated animals, but their demographic history is little understood. Here we analyzed nuclear polymorphism and mitochondrial data (mtDNA) from ancient central and west Anatolian sheep dating from Epipaleolithic to late Neolithic, comparatively with modern-day breeds and central Asian Neolithic/Bronze Age sheep (OBI). Analyzing ancient nuclear data, we found that Anatolian Neolithic sheep (ANS) are genetically closest to present-day European breeds relative to Asian breeds, a conclusion supported by mtDNA haplogroup frequencies. In contrast, OBI showed higher genetic affinity to present-day Asian breeds. These results suggest that the east-west genetic structure observed in present-day breeds had already emerged by 6000 BCE, hinting at multiple sheep domestication episodes or early wild introgression in southwest Asia. Furthermore, we found that ANS are genetically distinct from all modern breeds. Our results suggest that European and Anatolian domestic sheep gene pools have been strongly remolded since the Neolithic

    A SEMI-AUTOMATED POINT CLOUD PROCESSING METHODOLOGY FOR 3D CULTURAL HERITAGE DOCUMENTATION

    No full text
    The preliminary phase in any architectural heritage project is to obtain metric measurements and documentation of the building and its individual elements. On the other hand, conventional measurement techniques require tremendous resources and lengthy project completion times for architectural surveys and 3D model production. Over the past two decades, the widespread use of laser scanning and digital photogrammetry have significantly altered the heritage documentation process. Furthermore, advances in these technologies have enabled robust data collection and reduced user workload for generating various levels of products, from single buildings to expansive cityscapes. More recently, the use of procedural modelling methods and BIM relevant applications for historic building documentation purposes has become an active area of research, however fully automated systems in cultural heritage documentation still remains open. In this paper, we present a semi-automated methodology, for 3D façade modelling of cultural heritage assets based on parametric and procedural modelling techniques and using airborne and terrestrial laser scanning data. We present the contribution of our methodology, which we implemented in an open source software environment using the example project of a 16th century early classical era Ottoman structure, Sinan the Architect’s Şehzade Mosque in Istanbul, Turkey

    Integrable systems from inelastic curve flows in 2-and 3-dimensional Minkowski space

    No full text
    Integrable systems are derived from inelastic flows of timelike, spacelike, and null curves in 2-and 3- dimensional Minkowski space. The derivation uses a Lorentzian version of a geometrical moving frame method which is known to yield the modified Korteveg-de Vries (mKdV) equation and the nonlinear Schrodinger (NLS) equation in 2- and 3- dimensional Euclidean space, respectively. In 2-dimensional Minkowski space, time-like/space-like inelastic curve flows are shown to yield the defocusing mKdV equation and its bi-Hamiltonian integrability structure, while inelastic null curve flows are shown to give rise to Burgers' equation and its symmetry integrability structure. In 3-dimensional Minkowski space, the complex defocusing mKdV equation and the NLS equation along with their bi-Hamiltonian integrability structures are obtained from timelike inelastic curve flows, whereas spacelike inelastic curve flows yield an interesting variant of these two integrable equations in which complex numbers are replaced by hyperbolic (split-complex) numbers

    Immigrant children in Turkey a descriptive study: Determining the depression levels of children who have been exposed to forced migration

    No full text
    Purpose: The aim of this study was to determine the level of depression in children aged 6–17 years who had been subject to forced migration. Design and Method: This study was a descriptive design. The sample included comprised 200 children aged 6–17 years who had experienced forced migration. Findings: About 69.5% of the children who participated in the research migrated from Syria due to war. Participants’ mean Children's Depression Inventory (CDI) score was 13.65 ± 8.58; a CDI score of 19 and higher is considered to indicate depression. Conclusion: It was found that the depression levels of the migrant children were low. Practice Implications: Psychiatric nurses should understand risk factors for depression when providing care to immigrant children

    Cell type specificity of neurovascular coupling in cerebral cortex

    Get PDF
    Identification of the cellular players and molecular messengers that communicate neuronal activity to the vasculature driving cerebral hemodynamics is important for (1) the basic understanding of cerebrovascular regulation and (2) interpretation of functional Magnetic Resonance Imaging (fMRI) signals. Using a combination of optogenetic stimulation and 2-photon imaging in mice, we demonstrate that selective activation of cortical excitation and inhibition elicits distinct vascular responses and identify the vasoconstrictive mechanism as Neuropeptide Y (NPY) acting on Y1 receptors. The latter implies that task-related negative Blood Oxygenation Level Dependent (BOLD) fMRI signals in the cerebral cortex under normal physiological conditions may be mainly driven by the NPY-positive inhibitory neurons. Further, the NPY-Y1 pathway may offer a potential therapeutic target in cerebrovascular disease. DOI: http://dx.doi.org/10.7554/eLife.14315.00
    corecore