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Co3O4 is a promising catalyst for removing CO from H2 streams via the preferential CO oxidation (PROX). A Mars-van-Krevelen redox mechanism is often suggested but a detailed knowledge especially of the oxidation state of the catalytically active surface under reaction conditions is typically missing. We have thus utilized operando X-ray absorption spectroscopy to examine structure and oxidation state during PROX, and near atmospheric pressure-XPS at low photoelectron kinetic energies and thus high surface sensitivity to monitor surface composition changes. The rather easy surface reduction in pure CO (starting already at ∼100 °C) and the easy reoxidation by O2 suggest that molecularly adsorbed CO reacts with lattice oxygen, which is replenished by gas phase O2. Nevertheless, the steady state concentration of oxygen vacancies under reaction conditions is too low even for XPS detection so that both the bulk and surface of Co3O4 appear fully oxidized during PROX. Furthermore, the effect of adding CeO2 (a less active material) to Co3O4 was studied. Promotion of Co3O4 with 10 wt% CeO2 increases the reduction temperatures in CO and H2 and enhances the PROX activity. Since CeO2 is a less active material, this can only be explained by a higher activity of the Co-O-Ce interface.

The aim of this study was to screen potential probiotic bacteria against Aeromonas hydrophila and determine the effects of antagonistic bacteria and a commercial product containing lactic acid bacteria on the survival and growth of stage II Astacus leptodactylus juveniles. For this purpose, a total of 110 bacterial strains were isolated from adult, stage II crayfish juveniles and rearing water screened for antagonistic activities against A. hydrophila with well diffusion agar assay. Hafnia alvei strain from stage II crayfish juveniles displayed the inhibition zone (10mm) against A. hydrophila. The experiment was conducted in a completely randomized design with four treatments for 60 days: (I) crayfish fed with live food without probiotics (control group); (II) crayfish fed with live food enriched with lactic acid bacteria (0.015 gL(-1)); (III) crayfish fed with live food enriched with Hafnia alvei (106 CFU mL(-1)); (IV) crayfish fed with control diet and H. alvei added to rearing water (106 CFU mL(-1)). As a result of this study, lactic acid bacteria and Hafnia alvei applications did not positively affect growth and survival of stage II A. leptodactylus juveniles. In the future, studies on screening potential probiotic bacteria should be used in vitro and in vivo tests. In addition, it will be useful to investigate the lactic acid bacteria and Bacillus spp. from indigenous microflora of crayfish.

Plecotus auritus and Plecotus austriacus were recorded from 8 and 3 localities in the Asiatic part of Turkey, respectively. It was determined that the length of the first premolar, the shape of the zygomatic arches and baculum distinguish these taxa from each other. Apart from these morphological characteristics, the tibia length of P. austriacus was found to be significantly greater than that of P. austriacus (P < 0.05). The diploid chromosome numbers were identical in both taxa (2n = 32). The number of chromosomal arms (FN = 54) and the number of autosomal chromosomal arms (FNa = 50) were the same as in previously published papers on P. austriacus.

WOS: 000310069000012, Past climatic fluctuations influenced forest habitats and impacted heavily the distribution of forest species, such as the edible dormouse, by changing the distribution and composition of forests themselves. Such effects may be valid for ongoing climate change as well. To improve our understanding of the edible dormouse's history and how it responded to changes in its environment, we investigated its variation across the understudied zone of Northern Turkey using two complementary markers of differentiation: the mitochondrial cytochrome b gene for genetics, and size and shape of the first upper molar for phenotypic differences. Genetic and morphometric results were strongly discrepant. Genetic analyses evidenced an amazing homogeneity throughout the Eurasian range of the edible dormouse, whereas morphometrics pointed to a complex, step-wise differentiation along the Black Sea coast, the main signal being an opposition between Easternmost and Westernmost Turkish dormice. The genetic homogeneity suggests that this phenotypic differentiation is not the inheritance of glacial refuges, but the consequence of a more recent post-glacial isolation. The transition between the European and Asian groups is located eastwards from the Marmara straits, undermining its claimed role as an efficient barrier but stressing the importance of climatic and vegetational factors. A secondary differentiation between populations from the Central Black Sea coast and Easternmost regions was evidenced, attributed to a complex interplay of climatic, topographic, anthropogenic, and ecological factors. Turkey, at the crossroad of European and Asian species, heavily impacted by the current global change including climatic and anthropogenic factors, appears of importance for understanding the historical dynamics of differentiation and exchanges between populations that shaped the current distribution of Eurasian species and their future survival. (C) 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, , ., Council of Higher Education in Turkey (YOK); TUBITAK [105T068], We thank Prof. Dr Engin Unay, Associate Prof. Sakir Ozkurt, Res. Asst. Guliz Yavuz and two anonymous reviewers who provided valuable comments at earlier points in the study. The Council of Higher Education in Turkey (YOK) supported Z.H. by a scholarship to visit the University of Lyon. This study was partially funded by TUBITAK (105T068).

The effects of commercial cellulase enzyme products on the nutritive value of canola meal (CM) were determined in tilapia fry. Nine diets were prepared by adding cellulase enzyme (1-5 g kg(-1)) to control diet (containing no canola), low canola (41.7 g kg(-1) CM) and high canola (208.3 g kg(-1) CM). Tilapia fry was fed for 90 days, and growth, feed conversion ratio (FCR), body composition and nutrient digestibility were determined. Fish fed the diets containing the lowest levels of canola meal (41.7 g kg(-1)) had similar final weight and FCR relative to the group fed the control diet, and high canola diet showed significantly lower growth than other groups (P < 0.05), irrespective of cellulase enzyme. The addition of canola meal to tilapia diets resulted in lower protein digestibility and cellulose digestibility. There were no significant differences in body compositions in all treatments. Addition of enzymes to canola meal diets had no significant effects on growth performance, body compositions and nutrient digestibility. The results of this study indicate that use in higher level of canola meal in tilapia diet was adversely affected growth parameters and FCR. Adding dietary cellulase enzyme in different rations to diets showed no significant differences in growth parameter.

The main objective of this work was to study the effectiveness of iron oxide-coated pumice and volcanic slag particles in removing disinfection by-product (DBP) precursors from a raw drinking water source with high specific UV absorbance (SUVA(254)) value. Iron oxide coating of particles significantly increased dissolved organic carbon (DOC) uptakes and decreased DBP formation after chlorination compared to uncoated particles. pH values close to neutral levels during adsorption and chlorination provided DOC, trihalomethane and haloacetic acid reductions around 60-75% employing 6 g/L coated particle dosage. Higher degree of DOC and DBP reductions (>85%) were obtained with increasing particle dose. The uptake of bromide by iron oxide surfaces was negligible and increasing bromide concentrations (up to 550 mu g/L) did not negatively impact the DOC uptake. However, due to competition between natural organic matter (NOM) and bicarbonate for the iron oxide surfaces, increasing bicarbonate alkalinity levels reduced DOC uptakes. Overall, the results indicated that the iron oxide-coated pumice/slag particles are effective adsorbents to remove NOM and control DBP formation in waters with relatively high DOC and SUVA(254) levels. However, they may not be effective for waters with alkalinity levels above 250 mg CaCO3/L. (C) 2010 Elsevier B.V. All rights reserved.

Dryomys nitedula occurring in Turkish Thrace and Anatolia, and Dryomys laniger were morphologically and biometrically compared to each other. In addition, the blood serum proteins of D. nitedula and D. laniger were examined by the SDS - PAGE technique. There are very small morphological differences among the populations of D. nitedula, but the shapes of the braincase, tympanic bullae and mandible morphologically distinguished D. nitedula from D. laniger. In pair-wise biometric comparisons, nine biometric characteristics were found to differ statistically between D. nitedula (Thrace) and D. nitedula (Anatolia), 16 characteristics between D. nitedula (Turkish Thrace) and D. laniger, I I characteristics between D. nitedula (Anatolia) and D. laniger (p < 0.05). UPGMA cluster analysis established links between D. nitedula (Turkish Thrace) and D. nitedula (Anatolia) with a distance of 0.042, and D. laniger was connected to this cluster with a distance of 0.084. In the patterns of blood serum proteins, eight or nine bands were identified in the globulin zone, one band in the post-albumin and albumin zones and one or two bands in the pre-albumin zone of both species.

The Habitat, external and cranial morphologies, and karyotype of Turkish specimens of Tatera Indica are described for the first time with this study. It was determined that Tatera Indica was located in uncultivated arid and semi-arid habitat in southeastern Turkey. Its external and cranial characteristics are consistent with those detailed in published papers. The karyotype of Tatera indica is composed of 2n=68, NF=84 and NFa=80.