An archaeological mystery revealed by radiocarbon dating of cross-flow nanofiltrated amino acids derived from bone collagen, silk, and hair: case study of the bishops Baldwin I and Radbot II from Noyon-Tournai

Excavations in the cathedral of Tournai revealed two sepultures, which were identified by the excavators as those of bishops because of their special location in the cathedral. One burial was assigned to Baldwin I, who died in AD 1068, because (1) a ring with the inscription "BAL" was found and (2) a funeral stone with text was present on top of the grave mentioning the name Baldewinus. The second burial probably belongs to Radbot II, who was the successor of Baldwin I, and died in AD 1098. Both burials contained textiles (silk), the skeleton, a wooden pastoral staff, and human hair was still present on the skull of what was presumed to be Radbot II. All the protein-containing materials were degraded and/or contaminated. Standard sample pretreatment methods were not able to remove all the contaminants. Single and double cross-flow nanofiltration of the hydrolyzed protein-containing materials were performed. The sample quality for radiocarbon dating was improved and C-14 data revealed interesting and surprising results. The C-14 dates of the wooden pastoral staff and permeate femur confirm that the skeleton and tomb belong to bishop Baldwin I. The C-14 dates of hair and permeate skull indicate that the skeleton may indeed belong to bishop Radbot II. The younger C-14 dates of the wooden pastoral staff and silk samples indicate a postburial disturbance of the site burial during the 12th-13th century

The role of Dnmts and Tets in shaping the DNA methylation landscape of mouse embryonic stem cells

DNA methylation is an important epigenetic mark, which is set and maintained by DNA methyltransferases (Dnmts) and removed via passive or active mechanisms involving Ten eleven translocation enzyme (Tet) mediated oxidation. Stable cell type specific methylation patterns can only be achieved if methylation and demethylation events are in balance. Yet, the genome wide regulation of Dnmt and Tet activity is still not fully understood. The present studies use novel hairpin sequencing techniques coupled with oxidative bisul te sequencing, which permits the simultaneous and strand speci c detection of 5- methylcytosine and 5-hydroxymethylcytosine. Application of HMM models then facilitates the estimation of enzyme efficiencies for Dnmts and Tets. Furthermore, spatial modelling of hairpin bisulfite data allows the investigation of how Dnmts interpret preexisting methylation patterns. Taken together, the results of the presented studies show that methylation and hydroxylation are antagonistic, but not mutual exclusive events. In this context, the data shows that Tet efficiency is highest at open and accessible chromatin. Furthermore, the absence of Tets leads to a considerable misregulation of Dnmts, resulting in an increase in both maintenance and de novo methylation efficiency. Lastly, the spatial analysis of methylation patterns reveals that the de novo methyltransferases Dnmt3a and 3b depend in their activity on pre-existing neighbouring CpG methylation.DNA Methylierung is eine epigenetische Modifikation, welche durch DNA Methyltransferasen (Dnmts) gesetzt und beibehalten wird. Entfernt wird DNA Methylierung durch aktive oder passive Mechanismen welche die Oxidation von DNA Methylierung durch Ten- Eleven Translocation Enzyme (Tets) involviert. Stabile, Zelltyp-spezifische Methylierungsmuster können nur erreicht werden, wenn Methylierungs- und Demethylierungsvorgänge im Gleichgewicht sind. Dennoch ist die genomweite Regulation von Dnmts und Tets nicht vollständig geklärt. Die hier gezeigten Studien verwenden neue Hairpin-Sequenzierungs-Verfahren, gekoppelt mit oxidativer Bisulfit-Sequenzierung, was eine simultane und strangspezifische Analyse von 5-Methylcytosin und 5-Hydroxymethylcytosin erlaubt. Die Anwendung von hid- den Markov Modellen erlaubt im Anschluss die Berechnung von Enzymeeffizienzen für Dnmts und Tets. Darüber hinaus erlaubt eine räumliche Modellierung von Methylierungsmustern die Untersuchung, wie Dnmts bereits bestehende Methylierung interpretieren. Die Ergebnisse zeigen, dass Methylierung und Hydroxylierung antagonistische, aber keinesfalls sich ausschließende Ereignisse sind. Dabei zeigen Tets ihre stärkste Aktivität an offenem und zugänglichem Chromatin. Zudem führt der Verlust von Tets zu einer deutlichen Missregulation von Dnmts, welche sich durch eine Zunahme der Maintenance und de novo-Methylierungseffizienz äußert. Schließlich zeigt die räumliche Modellierung, dass die de novo-Methyltransferasen bei ihrer Aktivität abhängig von bereits bestehender DNA Methylierung sind

Experimental study of the flow field in patient specific lower airways

In this study Particle Image Velocimetry (PIV) is used to visualize and measure airflow in the lower airways. Using Rapid Prototyping Manufacturing (RPM) technology, a hydraulic in vitro model was developed and constructed. Preliminary 2D PIV measurements compared successfully to Computational Fluid Dynamics (CFD) results

Understanding CME and associated shock in the solar corona by merging multi wavelengths observation

Using multi-wavelength imaging observations, in EUV, white light and radio, and radio spectral data over a large frequency range, we analyzed the triggering and development of a complex eruptive event. This one includes two components, an eruptive jet and a CME which interact during more than 30 min, and can be considered as physically linked. This was an unusual event. The jet is generated above a typical complex magnetic configuration which has been investigated in many former studies related to the build-up of eruptive jets; this configuration includes fan-field lines originating from a corona null point above a parasitic polarity, which is embedded in one polarity region of large Active Region (AR). The initiation and development of the CME, observed first in EUV, does not show usual signatures. In this case, the eruptive jet is the main actor of this event. The CME appears first as a simple loop system which becomes destabilized by magnetic reconnection between the outer part of the jet and the ambient medium. The progression of the CME is closely associated with the occurrence of two successive types II bursts from distinct origin. An important part of this study is the first radio type II burst for which the joint spectral and imaging observations allowed: i) to follow, step by step, the evolution of the spectrum and of the trajectory of the radio burst, in relationship with the CME evolution; ii) to obtain, without introducing an electronic density model, the B-field and the Alfven speed.Comment: 17 pages, 13 figure