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Occupied between ~10,300 and 9300 years ago, the Pre-Pottery Neolithic site of Aşıklı Höyük in Central Anatolia went through early phases of sheep domestication. Analysis of 629 mitochondrial genomes from this and numerous sites in Anatolia, southwest Asia, Europe, and Africa produced a phylogenetic tree with excessive coalescences (nodes) around the Neolithic, a potential signature of a domestication bottleneck. This is consistent with archeological evidence of sheep management at Aşıklı Höyük which transitioned from residential stabling to open pasturing over a millennium of site occupation. However, unexpectedly, we detected high genetic diversity throughout Aşıklı Höyük's occupation rather than a bottleneck. Instead, we detected a tenfold demographic bottleneck later in the Neolithic, which caused the fixation of mitochondrial haplogroup B in southwestern Anatolia. The mitochondrial genetic makeup that emerged was carried from the core region of early Neolithic sheep management into Europe and dominates the matrilineal diversity of both its ancient and the billion-strong modern sheep populations. [ABSTRACT FROM AUTHOR]

In this article, we review the publications served by theCanadian Journal of Science, Mathematics and Technology Educationin the past 15 years, specific to the field of mathematics education, and make connections with development of the field. In particular, we adopt current Editor-in-Chief John Wallace's (2009) approach of “looking back, looking forward,” to reflect on the journal's development both qualitatively, by recapping significant moments of the journal and highlighting recurrent themes, and quantitatively, by reviewing the number of contributions in terms of country, language, and genre. In looking forward, we inform a discussion of future directions of the journal. [ABSTRACT FROM PUBLISHER]

Dating silk mounting textiles is important for understanding their condition and susceptibility to degradation. Amino acid racemization is a technique currently used for this purpose. The research presented here aimed to clarify when this technique is reliable and when it is not. Silk fibers taken from a cocoon and from Japanese mounting textiles were studied using optical microscopy to document surface roughness. Chiral capillary electrophoresis mass spectrometry for amino acid racemization dating (AAR), liquid chromatography mass spectrometry for dye analysis, and FTIR for analysis of sericin and other materials adhering to the silk were also used. A change from rough fiber surfaces (greater than a hundred years old) to smooth fiber surfaces (less than a hundred years) was found. This correlated with the time of the introduction of Western degumming methods in Japan. Synthetic dyes were not found on the earlier silk fibers with rough surfaces. AAR dating measurements on rough surfaced fibers with remaining sericin correlated better with the estimated age of the silk fabrics than fibers with smooth surfaces, suggesting the technique should only be used for silk fibers with rough surfaces. A screening method for fibers for AAR analysis was outlined. [ABSTRACT FROM AUTHOR]

Palmer amaranth (Amaranthus palmeri S. Wats.) is a highly competitive weed that can be difficult to manage in many cropping systems. Research to date has not quantified the growth and development of A. palmeri in a manner that allows direct comparisons across cropping systems. Research was conducted to compare the growth, development, and seed production of A. palmeri when competing with corn (Zea mays L.), cotton (Gossypium hirsutum L.), peanut (Arachis hypogaea L.), and soybean [Glycine max (L.) Merr.] when emerging with crops or emerging three weeks after crops emerge. Regardless of when A. palmeri emerged, seed production was greatest and similar in cotton and peanut and exceeded that of corn and soybean; seed production in soybean exceeded that of corn. However, seed production was approximately 10-fold greater when A. palmeri emerged with crops compared with emergence three weeks later. These results illustrate the importance of controlling weeds during the first three weeks of the season relative to contributions of A. palmeri to the weed seed bank and is the first report comparing seed production in presence of these crops in a manner allowing a statistical comparison of seed production and highlighting the importance of crop sequence for seed bank management. [ABSTRACT FROM AUTHOR]

Scientific imaging of a large fragile work of art can be especially challenging, but especially rewarding to better grasp the complexity and changes that have occurred during its creation and lifetime. Here, noninvasive imaging, macro X-ray fluorescence (MAXRF) imaging spectroscopy and reflectance imaging spectroscopy, from the visible to the near infrared spectral range, are utilized to document a 14-m-long Japanese narrative handscroll, The Miraculous Interventions of Jizō Bosatsu. Due to the scroll's age and its handling during past use as a teaching tool, it has a number of conservation needs and shows evidence of past repairs. The scroll has extensive and severe creasing, breaks and tears, as well as unstable and powdering pigments. Microscopic observation and scientific analyses were performed both to document the current condition of the scroll and to better understand its long history. Combining RIS and MAXRF allowed for pigment characterization through elemental and molecular information. While RIS and MAXRF previously have been applied to the study of other painted materials, their application to East Asian paintings is rare. The obstacles of the scroll's length and fragile uneven surface were overcome by optimizing the setups of the two imaging systems. The MAXRF and RIS analyses, here focused on a select scene of the scroll, found certain original pigments common in early Japanese scroll paintings were used frequently, such as vermilion, iron-based compounds (yellow and red ochres), and copper-containing greens, while others occurred sparingly, such as azurite and red lead. A chloride-containing lead-based white pigment was employed. Faded organic colorants, notably indigo as well as an organic yellow/brown, could be detected but their vibrancy has been muted over the centuries. In the case of indigo, it may be visibly observed in some areas; however, analysis revealed its previously unknown presence mixed with a copper green in a select area. This focused study sets a foundation for further studies on both this object and other Asian works of art. [ABSTRACT FROM AUTHOR]

Genome-wide analysis of 67 ancient Near Eastern cattle, Bos taurus, remains reveals regional variation that has since been obscured by admixture in modern populations. Comparisons of genomes of early domestic cattle to their aurochs progenitors identify diverse origins with separate introgressions of wild stock. A later region-wide Bronze Age shift indicates rapid and widespread introgression of zebu, Bos indicus, from the Indus Valley. This process was likely stimulated at the onset of the current geological age, ~4.2 thousand years ago, by a widespread multi-century drought. In contrast to genome-wide admixture, mitochondrial DNA stasis supports that this introgression was male-driven, suggesting that selection of arid-adapted zebu bulls enhanced herd survival. This human-mediated migration of zebu-derived genetics has continued through millennia, altering tropical herding on each continent. [ABSTRACT FROM AUTHOR]

The article presents a study in which genomic data from ancient goats from Paleolithic to Medieval contexts was used to determine the location and mode of domestication of goats in the Fertile Crescent.

The article presents a letter to the editor in response to the article "Diagnosis and treatment of low back pain," by Koes et al.