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Fossil biomolecules from an endogenous source were previously identified in Cretaceous to Pleistocene fossilized bones, the evidence coming from molecular analyses. These findings, however, were called into question and an alternative hypothesis of the invasion of the bone by bacterial biofilm was proposed. Herewith we report a new finding of morphologically preserved blood-vessel-like structures enclosing organic molecules preserved in iron-oxide-mineralized vessel walls from the cortical region of nothosaurid and tanystropheid (aquatic and terrestrial diapsid reptiles) bones. These findings are from the Early/Middle Triassic boundary (Upper Roetian/Lowermost Muschelkalk) strata of Upper Silesia, Poland. Multiple spectroscopic analyses (FTIR, ToF-SIMS, and XPS) of the extracted "blood vessels" showed the presence of organic compounds, including fragments of various amino acids such as hydroxyproline and hydroxylysine as well as amides, that may suggest the presence of collagen protein residues. Because these amino acids are absent from most proteins other than collagen, we infer that the proteinaceous molecules may originate from endogenous collagen. The preservation of molecular signals of proteins within the "blood vessels" was most likely made possible through the process of early diagenetic iron oxide mineralization. This discovery provides the oldest evidence of in situ preservation of complex organic molecules in vertebrate remains in a marine environment.

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The paper reports a new route for the fabrication and determination of physicochemical properties and biological activity, of metallic silica-based nanostructure (Ag/SiO2, Cu/SiO2).

Mechano-chemical synthesis of Cu-doped BiVO4 monoclinic nanopowders and investigation of structural, optical and electronic properties.

Nickel titanate (NiTiO 3 ) thin films were grown by a radio frequency magnetron co-sputtering process using metal (Ni and Ti) targets on fused quartz substrates at a substrate temperature of 400 C. Annealing of asdeposited (amorphous) films was performed at 1100 C for 2 hours to realize a stable crystalline phase. The effect of the Ti target power (200 and 250 W) and nitrogen doping on the structural, morphological and optical properties of post-annealed NiTiO 3 thin films were investigated besides photocatalytic activity under visible light irradiation. X-ray diffraction measurement on the films revealed a pure ilmenite phase at 250 W Ti power. Preferential orientation changed from [104] to [110] as Ti power increased from 200 to 250 W. Raman studies on NiTiO 3 thin films showed almost all the active modes (5A g + 5E g ) of a crystalline structure. Two different microstructures were observed by scanning electron microscopy, films showed rounded (250 nm) grains at 200 W Ti target power while facet forms (500 nm) develop in the films deposited at 250 W. Chemical bonding and valence states of the involved ions such as Ni 2p, Ti 2p and O 1s were investigated by X-ray photoelectron spectroscopy. Nitrogen doping modifies the rms roughness from 12 nm to 17 nm as demonstrated on 200 W grown films and contributes also to modify the indirect optical band gap from 2.50 to 2.43 eV in films obtained at 250 W Ti target power. As a crucial role of nitrogen doping, photocatalytic activity in a broad visible light range was observed with a good efficiency for the degradation of methylene blue by nitrogen doped NiTiO 3 thin films.

Crystal structure and temperature dependence of magnetic susceptibility and electrical resistivity have been determined for GdTiSi and GdTiGe. Both compounds order ferromagnetically and for GdTiGe TC is 374 K which is a very high value for such kinds of compounds. The electronic structure for both compounds has been investigated by photoelectron spectroscopy and compared with calculations performed using the TB-LMTO method. A very good agreement with experiment was obtained, especially for GdTiGe. A strong hybrydization between the d states from Gd and Ti was found and a significant polarization of the Ti 3d electrons in GdTiGe was obtained which may be related to the enhanced indirect exchange between Gd magnetic moments.

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