High-K volcanism in the Afyon region, western Turkey: from Si-oversaturated to Si-undersaturated volcanism

Volcanic rocks of the Afyon province (eastern part of western Anatolia) make up a multistage potassic and ultrapotassic alkaline series dated from 14 to 12 Ma. The early-stage Si-oversaturated volcanic rocks around the Afyon city and further southward are trachyandesitic volcanic activity (14.23 ± 0.09 Ma). Late-stage Si-undersaturated volcanism in the southernmost part of the Afyon volcanic province took place in three episodes inferred from their stratigraphic relationships and ages. Melilite– leucitites (11.50 ± 0.03 Ma), spotted rachyandesites, tephryphonolites and lamproites (11.91 ± 0.13 Ma) formed in the first episode; trachyandesites in the second episode and finally phonotephrites, phonolite, basaltic trachyandesites and nosean-bearing trachyandesites during the last episode. The parameter Q [normative q-(ne + lc + kls + ol)] of western Anatolia volcanism clearly decreased southward with time becoming zero in the time interval 10–15 Ma. The magmatism experienced a sudden change in the extent of Si saturation after 14 Ma, during late-stage volcanic activity of Afyon volcanic province at around 12 Ma, though there was some coexistence of Si-oversaturated and Si-undersaturated magmas during the whole life of Afyon volcanic province

In vaginal fluid, bacteria associated with bacterial vaginosis can be suppressed with lactic acid but not hydrogen peroxide

<p>Abstract</p> <p>Background</p> <p>Hydrogen peroxide (H₂O₂) produced by vaginal lactobacilli is generally believed to protect against bacteria associated with bacterial vaginosis (BV), and strains of lactobacilli that can produce H₂O₂are being developed as vaginal probiotics. However, evidence that led to this belief was based in part on non-physiological conditions, antioxidant-free aerobic conditions selected to maximize both production and microbicidal activity of H₂O₂. Here we used conditions more like those <it>in vivo </it>to compare the effects of physiologically plausible concentrations of H₂O₂and lactic acid on a broad range of BV-associated bacteria and vaginal lactobacilli.</p> <p>Methods</p> <p>Anaerobic cultures of seventeen species of BV-associated bacteria and four species of vaginal lactobacilli were exposed to H₂O₂, lactic acid, or acetic acid at pH 7.0 and pH 4.5. After two hours, the remaining viable bacteria were enumerated by growth on agar media plates. The effect of vaginal fluid (VF) on the microbicidal activities of H₂O₂and lactic acid was also measured.</p> <p>Results</p> <p>Physiological concentrations of H₂O₂(< 100 μM) failed to inactivate any of the BV-associated bacteria tested, even in the presence of human myeloperoxidase (MPO) that increases the microbicidal activity of H₂O₂. At 10 mM, H₂O₂inactivated all four species of vaginal lactobacilli but only one of seventeen species of BV-associated bacteria. Moreover, the addition of just 1% vaginal fluid (VF) blocked the microbicidal activity of 1 M H₂O₂. In contrast, lactic acid at physiological concentrations (55-111 mM) and pH (4.5) inactivated all the BV-associated bacteria tested, and had no detectable effect on the vaginal lactobacilli. Also, the addition of 10% VF did not block the microbicidal activity of lactic acid.</p> <p>Conclusions</p> <p>Under optimal, anaerobic growth conditions, physiological concentrations of lactic acid inactivated BV-associated bacteria without affecting vaginal lactobacilli, whereas physiological concentrations of H₂O₂produced no detectable inactivation of either BV-associated bacteria or vaginal lactobacilli. Moreover, at very high concentrations, H₂O₂was more toxic to vaginal lactobacilli than to BV-associated bacteria. On the basis of these <it>in vitro </it>observations, we conclude that lactic acid, not H₂O₂, is likely to suppress BV-associated bacteria <it>in vivo</it>.</p

A rare central nervous system tumor of childhood with spongiform appearance on brain magnetic resonance imaging; primary diffuse leptomeningeal oligodendrogliomatosis [Un raro tumor del sistema nervioso central de la infancia con apariencia espongiforme en la resonancia magnética cerebral; oligodendrogliomatosis leptomeníngea difusa primaria]

2-s2.0-85100396296Primary diffuse leptomeningeal oligodendrogliomatosis is a rare fatal tumor of childhood. Symptoms usually occur when the tumor causes hydrocephalus. Brain magnetic resonance imaging (MRI) may be nearly normal in the early stages of the disease, while hydrocephalus and multiple leptomeningeal cysts with spongiform appearance may appear later on. One may consider the diagnosis when radiologic findings become apparent with multiple leptomeningeal cysts. However, failure to recognize the imaging findings due to the rarity of the disease may delay the diagnosis. Here, we report a 3.5-year-old girl who presented with ataxia and vomiting and had a diagnosis of primary diffuse leptomeningeal glioneuronal tumor with remarkable brain MRI findings as diffuse multiple tiny cystic lesions on the brain and spinal cord. She benefited from radiotherapy and temozolomide treatment with remission of brain MRI findings. Increasing the number of reported cases will enable the elucidation of the disease's pathogenesis and the development of treatment protocols. © 2021 Sociedad Española de Neurocirugí

Rapid and efficient microwave-assisted synthesis of some new triazol-3-one derivatives

A growing body of literature has shown the effectiveness of using microwaves in chemical reactions. The aim of this study is to demonstrate a rapid and highly efficient synthesis of some new triazol-3-ones via microwave heating using a monomode microwave. Compared with the thermal process, the microwave heating induces a dramatic reduction of the reaction time and improvement of the yields. In this study, rapid N-benzylation and N-acetylation of triazol-3-ones were achieved by microwave irradiation method for the first time. The newly synthesized compounds showed moderate antimicrobial activity against the standard bacterial and fungal organisms tested. © 2013 HeteroCorporation

Flux Pinning in YBCO Single Crystal Grown on Y2O3 Layer

Karadeniz Technical University research grant (BAP-2008.111.001.8).In this study, single-crystal Y123 samples were grown by a cold top-seeding method by using Nd123 seed, and the effect of Y2O3 buffer layer was investigated. The upper critical magnetic field and coherence length were established as 110 T and 17.3 ´ Å, respectively. The dependence of the effective activation energy U of the flux pinning on the magnetic field and temperature of the sample were determined using the Arrhenius activation energy law from the resistivity curves. It was found that the deduced value of the activation energy for a Y123 sample is in good agreement with the corresponding values in YBCO samples. The maximum activation energy value was approximately 0.9 eV in the zero magnetic field. In order to examine the homogeneity of the pinning properties of different layers, rectangular specimens were cut from the sample. AC susceptibility measurement was performed, and it was found that the shifting of the peak temperature (Tp) with an AC magnetic field is small, indicating good pinning properties. The normalized pinning force density versus the reduced field was examined at different temperatures to determine the pinning mechanism. It was found that normal core-type pinning was effective, and in low fields, pinning was only due to Y211 particles

Experimental and computational studies on 4-[(3,5-dimethyl-1H-pyrazol-1-yl) methoxy]phthalonitrile and synthesis and spectroscopic characterization of its novel phthalocyanine magnesium(ii) and tin(ii) metal complexes

PubMed: 23800773The molecular structure of the substituted phthalonitrile was analyzed crystallographically and compared with optimized geometric structure. The structural properties of the compound such as energy, vibrational frequency, ground state transitions, 1H and 13C NMR chemical shifts, NBO analysis and hyper-polarizability were computed by DFT (Density Functional Theory) method and compared with experimental results. The novel Mg(ii) and Sn(ii) phthalocyanines synthesized from the substituted phthalonitrile and their aggregation behaviors were investigated in different solvents and at different concentrations in DMSO. © 2013 Elsevier B.V. All rights reserved

Synthesis and antimicrobial evaluation of novel di-triazoles and 4-arylidene amino 4,5 dihydro-1H-[1,2,4] triazole-5-one derivatives

A series of novel di-[3(thiophen-2-yl-methyl)-4,5-dihydro-1H-[1,2,4] triazole-5-one-4yl]n-alkanes (2a-h) were obtained by the reaction of N'-1-ethoxy-2-thiophen-2-yl-ethylydene hydrazino carboxylic acid ethyl ester (1) and diamines. Compound 3 was reacted with aldehydes and 4-(arylidene-amino)-3- thiophen-2-yl-methyl-4,5-dihydro-1H-[1,2,4] triazole-5-ones (4, 5, and 8) with Schiff base character were synthesized. (4-(arylidene-amino)-5-oxo-3-thiophen-2- yl-methyl-4,5-dihydro-1H-[1,2,4]triazole-1-yl)-acetic acid ethyl esters (6, 7, and 9) were obtained by the reaction of 4-(arylidene-amino)-3-thiophen-2-yl- methyl-4,5-dihydro-1H-[1,2,4]triazole-5-ones (4, 5, and 8) and ethyl bromoaeetate. The structures of the new compounds were inferred through IR, 1H/13C NMR, elemental analyses, and mass spectral data. Compound 8i was characterized by IR, 1H/13C NMR, elemental analyses, mass, and X-ray spectral techniques. Geometry optimization of compounds 2a, 2c, 2f, 4, and 5 was achieved by computer using the AM1 method. Compounds 2f, 4, 5, 6, 7, 8i, and 9k showed good antifungal activity only against yeast fungi, while compound 2d showed antimicrobial activity against the bacteria Pseudomonas aeruginosa ATCC10145, Enterococcus faecalis ATCC29212 and the yeast fungi Candida albicans ATCC 60193 and Candida tropicalis ATCC 13803. © TÜBITAK