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Abstract  

Three series of new copper and rare-earth metal tungstates with the formulas: CuRE 2W2O10 (RE = Nd, Sm, Eu) and Cu3 RE 2W4O18 (RE = Sm, Eu or RE = Dy, Ho, Er) were synthesized by the solid-state reaction method. The CuRE 2W2O10 and Cu3 RE 2W4O18 (RE = Dy, Ho, Er) compounds crystallize in the monoclinic system. The Cu3 RE 2W4O18 phases with the large rare-earth ions crystallize in the triclinic system. All obtained compounds melt incongruently below 1273 K. The anion lattice of the Cu3 RE 2W4O18 phases is built from isolated groups of octahedra (W4O16)8−, while CuRE 2W2O10 from WO6 octahedra forming structural elements [(W2O9)6−]. The EPR spectra of analyzed compounds consisted of an intense line originating generally from the rare-earth ions and a weak, narrow line from Cu2+ separate centers appearing only on the surface of the grains. The absence of bulk copper in the EPR spectrum is probably due to a very short relaxation time of the Cu2+ subsystem.

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The intraformational paleosol and calcareous muddy cavity fills interbedded in the travertine of the Vár-hegy (Castle Hill) in Budapest were analyzed for carbon and oxygen isotope compositions and compared with the isotope compositions of the host travertine. Microscopic investigations of these layers indicate mechanical reworking of the travertine and mixing with the allothigenic siliciclastic material. Micromorphological features, e.g. needle-fiber calcite, carbonate hypocoatings around pores, ferruginous precipitations and clay infillings in the paleosol and cavity fills indicate that in situ pedogenic processes were active in both layers. The presence of ferrihydrite in the A horizon of the paleosol also supports pedogenic alteration. The stable carbon and oxygen isotope compositions of bulk carbonate of paleosol and cavity fills (d13C= -0.6 to 2.1‰ and d 18O= -16.7 to -12.9‰) are very close to the compositions of the host travertine (d 13C=1.1 to 2.1‰ and d 18O = -17.7 to -13.7‰,) and differ from the probable isotope composition of pedogenic carbonate (d 13C values around -11‰). These results indicate that the studied paleosol and cavity fills have only minor pedogenic component (authigenic carbonate content up to 20%); thus the paleosol represents a weakly developed soil, mostly composed of travertine clasts and allothigenic siliciclastic material.

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JPC - Journal of Planar Chromatography - Modern TLC
Authors: Paco Noriega, Tatiana Mosquera, Erika Paredes, Michelle Parra, Morgana Zappia, Mónica Herrera, Abigail Villegas, and Edison Osorio

The present research evaluated the chemical composition as well as the antioxidant and antimicrobial properties of the essential oil from the bark of Ocotea quixos (Lam.) Kosterm. The major components of the essential oil were cinnamaldehyde <(E)-> (30.69%), methoxy cinnamaldehyde <(E)-o-> (16.29%), cinnamyl acetate <(E)-> (12.18%), and methyl cinnamate <(E)-> (5.72%). The antioxidant capacity showed to be superior to that of the essential oil of Tymus vulgaris. The results show low half maximal inhibitory concentration (IC50) values, which means that the essential oil has a high activity: 2,2-diphenyl-1-picrylhydrazyl (DPPH) IC50, 2.786 ± 0.150 mg mL−1; 2,2′-azino-di-(3-ethylbenzthiazoline sulfonic acid (ABTS) IC50, 0.240 ± 0.034 mg mL−1; and IC50 β-carotene test, 0.496 ± 0.017 mg mL−1. The essential oil was active with all the microorganisms evaluated, being very active against: Escherichia coli ATCC (American type culture collection) 25922, Staphylococcus aureus ATCC 29213, Listeria grayi ATCC 19120, Micrococcus luteus ATCC 4698, Trichophyton mentagrophytes ATCC 9533, and Trichophyton rubrum ATCC 13803. The bioautography assays showed that bergamoteno <α-trans-> and methoxy cinnamaldehyde <€-o-> were the responsible molecules for the antioxidant activity and cinnamyl acetate <€-> was the molecule responsible for the antimicrobial activity.

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European Journal of Microbiology and Immunology
Authors: Comoé Koffi Donatien Benie, Adjéhi Dadié, Nathalie Guessennd, Nadège Ahou N’gbesso-Kouadio, N’zebo Désiré Kouame, David Coulibaly N’golo, Solange Aka, Etienne Dako, Koffi Marcellin Dje, and Mireille Dosso

Pseudomonas aeruginosa owns a variability of virulence factors. These factors can increase bacterial pathogenicity and infection severity. Despite the importance of knowledge about them, these factors are not more characterized at level of strains derived from local food products. This study aimed to characterize the virulence potential of P. aeruginosa isolated from various animal products. Several structural and virulence genes of P. aeruginosa including lasB, exoS, algD, plcH, pilB, exoU, and nan1 were detected by polymerase chain reaction (PCR) on 204 strains of P. aeruginosa. They were isolated from bovine meat (122), fresh fish (49), and smoked fish (33). The 16S rRNA gene was detected on 91.1% of the presumptive strains as Pseudomonas. The rpoB gene showed that 99.5% of the strains were P. aeruginosa. The lasB gene (89.2%) was the most frequently detected (p < 0.05). In decreasing importance order, exoS (86.8%), algD (72.1%), plcH (72.1%), pilB (40.2%), and exoU (2.5%) were detected. The lasB gene was detected in all strains of P. aeruginosa serogroups O11 and O16. The prevalence of algD, exoS, and exoU genes in these strains varied from 51.2% to 87.4%. The simultaneous determination of serogroups and virulence factors is of interest for the efficacy of surveillance of infections associated with P. aeruginosa.

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genesis of wh -based correlatives: From indefiniteness to relativization . Paper presented at Sinn und Bedeutung 19, Göttingen . http://tinyurl.com/oq9bf4o (16/08/2015) Bende

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1970 Graphical method for examination of 18 O/ 16 O fractionations in silicate rocks Earth and Planetary Science Letters 10 12 16

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. Javoy 1980 18O/16O and D/H ratios in high temperatures peridotites Centre National de la Recherche Scientifique Colloque International 272 279

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1980 The effects of assimilation of country rocks by magmas on 18O/16O and 87Sr/86Sr systematics in igneous rocks Earth Plan. Sci. Lett. 47 243 254

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Acta Geologica Hungarica
Authors: Sándor Kele, Lászó Korpás, Attila Demény, Péter Kovács-Pálffy, Bernadett Bajnóczi, and Zsófia Medzihradszky

Opauszky, L., L. Matus, J. Lukács, I. Kiss 1964: Die Bestimmung der Paleotemperatur durch Messung des 18 O/ 16 O Isotopverhältnisses von Karbonaten. - In: Vértes, L. (Ed.): Tata, eine mittelpaläolithische Travertin-Siedlung in Ungarn. Akadémiai Kiadó

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of the third stage was attributed to V 2 O 5 (ICDD card 85–0601), and second to (NH 4 ) 2 V 6 O 16 (ICDD card 79–205). The assumption that the product of the first stage corresponds to (NH 4 ) 3 V 6 O 16 was made basing on the mass balance (there

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