Elemental mapping of moroccan enameled terracotta tile works (Zellij) based on X-ray micro-analyses

The purpose of this work is the elemental mapping of enameled terracotta samples (Zellij), produced between the 13th and 20th centuries in Morocco, collected from five different monuments from Marrakech. These pieces were analyzed by two non-destructive micro X-Ray Fluorescence (XRF) spectrometers, aiming to obtain elemental distribution and elemental composition.From the obtained spectra we have identified the main elements present in the tin-opacified lead glaze. The identification of the decoration colors is based on the different ratios between the fluorescence lines of the main component of the glaze (Pb-Lα line) and the fluorescence lines of the main components of the pigment (Co-Kα, Mn-Kα, Ni-Kα,. . lines). The semi-quantitative calculations based on these ratios revealed significant differences between modern and ancient samples. © 2013 Elsevier Ltd.Peer Reviewe

Study of Ferroelectric Bi 3.25 La 0.75 Ti 3 O 12 Thin Films Deposited by Sol-Gel Method

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Phosphorylation and activation of PINOID by the phospholipid signaling kinase 3-phosphoinositide-dependent protein kinase 1 (PDK1) in Arabidopsis

Activity of the serine-threonine protein kinase PINOID (PID) has been implicated in the asymmetrical localization of the membrane-associated PINFORMED (PIN) family of auxin transport facilitators. However, the means by which PID regulates PIN protein distribution is unknown. We have used recombinant PID protein to dissect the regulation of PID activity in vitro. We demonstrate that intramolecular PID autophosphorylation is required for the ability of PID to phosphorylate an exogenous substrate. PID-like mammalian AGC kinases act in a phosphorylation cascade initiated by the phospholipid-associated kinase, 3-phosphoinositide-dependent protein kinase 1 (PDK1), which binds to the C-terminal hydrophobic PDK1-interacting fragment (PIF) domain found in PDK1 substrates. We find that Arabidopsis PDK1 interacts with PID, and that transphosphorylation by PDK1 increases PID autophosphorylation. We show that a PID activation loop serine is required for PDK1-dependent PID phosphorylation. This activation is rapid and requires the PIF domain. Cell extracts from flowers and seedling shoots dramatically increase PID phosphorylation in a tissue-specific manner. A PID protein variant in which the PIF domain was mutated failed to be activated by the seedling shoot extracts. PID immunoprecipitated from Arabidopsis cells in which PDK1 expression was inhibited by RNAi showed a dramatic reduction in transphosphorylation of myelin basic protein substrate. These results indicate that AtPDK1 is a potent enhancer of PID activity and provide evidence that phospholipid signaling may play a role in the signaling processes controlling polar auxin transport