14C Calibration in the 2nd and 1st Millennia BC—Eastern Mediterranean Radiocarbon Comparison Project (EMRCP)

From the 20th International Radiocarbon Conference held in Kona, Hawaii, USA, May 31-June 3, 2009.We have measured additional known-age German oak samples in 4 intervals in the 2nd and 1st millennia BC to add to (and to replicate) parts of the international Northern Hemisphere radiocarbon calibration data set. In the 17th, 16th, and 12th centuries BC, our results agree well with IntCal04. In the 14th and 13th centuries BC, however, we observe a significant offset, with our results on average 27 yr older than IntCal04. The previously reported 14C offset between Anatolian juniper trees and central European oaks in the 9th and 8th centuries BC is smaller now, on the basis of our new measurements of German oak, but still evident. In the 17th and 16th centuries BC, the 14C ages from the Anatolian chronology agree well with IntCal04 and our new German oak data.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202

14C Record and Wiggle-Match Placement for the Anatolian (Gordion Area) Juniper Tree-Ring Chronology ~1729 to 751 cal BC, and Typical Aegean/Anatolian (Growing Season Related) Regional 14C Offset Assessment

The East Mediterranean Radiocarbon (inter-)Comparison Project (EMRCP) has measured the 14C ages of a number of sets of tree rings from the Gordion Area dendrochronology from central Anatolia at the Heidelberg Radiocarbon Laboratory. In several cases, multiple measurements were made over a period from the 1980s to 2009. This paper presents the final data set from this work (128 high-precision measurements), and considers (i) the relationship of these data against the standard Northern Hemisphere 14C calibration data set (IntCal09), and (ii) the optimum calendar dating of this floating tree-ring record on the basis of the final set of high-precision 14C data. It finds good agreement between the Anatolian data and IntCal09 in some important intervals (e.g. ~1729 to 1350 cal BC) and observes one period (9th-8th centuries BC) where there appears to be some indication of a regional/growing season signal, and another period (later 14th-13th centuries BC) where IntCal09 may not best reflect the real 14C record. The scale of the typical growing-season-related regional 14C offset (Delta-R) between the Aegean/Anatolian region and IntCal09 is also assessed (for the mid-2nd millennium BC and mid-2nd millennium AD), and found to be usually minor (at times where there are no major additional forcing factors and/or issues with the IntCal09 data set): of the order of 2-4 +/- 2-4 yr.The Radiocarbon archives are made available by Radiocarbon and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform February 202

Integrin-linked kinase, a novel component of the cardiac mechanical stretch sensor, controls contractility in the zebrafish heart

The vertebrate heart possesses autoregulatory mechanisms enabling it first to sense and then to adapt its force of contraction to continually changing demands. The molecular components of the cardiac mechanical stretch sensor are mostly unknown but of immense medical importance, since dysfunction of this sensing machinery is suspected to be responsible for a significant proportion of human heart failure. In the hearts of the ethylnitros-urea (ENU)-induced, recessive embryonic lethal zebrafish heart failure mutant main squeeze (msq), we find stretch-responsive genes such as atrial natriuretic factor (anf) and vascular endothelial growth factor (vegf) severely down-regulated. We demonstrate through positional cloning that heart failure in msq mutants is due to a mutation in the integrin-linked kinase (ilk) gene. ILK specifically localizes to costameres and sarcomeric Z-discs. The msq mutation (L308P) reduces ILK kinase activity and disrupts binding of ILK to the Z-disc adaptor protein β-parvin (Affixin). Accordingly, in msq mutant embryos, heart failure can be suppressed by expression of ILK, and also of a constitutively active form of Protein Kinase B (PKB), and VEGF. Furthermore, antisense-mediated abrogation of zebrafish β-parvin phenocopies the msq phenotype. Thus, we provide evidence that the heart uses the Integrin–ILK–β-parvin network to sense mechanical stretch and respond with increased expression of ANF and VEGF, the latter of which was recently shown to augment cardiac force by increasing the heart's calcium transients