I and I* convergent function sequences

In this paper, we introduce the concepts of I-pointwise convergence, I-uniform convergence,I*-pointwise convergence and I*-uniform convergence of function sequences and then we examine the relation between them

Trophic interactions of two Ponto-Caspian gobies in the Turkish part of their native range

Several Ponto-Caspian gobiids have expanded from their native distribution ranges to Europe and North America. As knowledge on their bio-ecological features in their native range is still limited, the trophic ecology of monkey goby Neogobius fluviatilis and Western tubenose goby Proterorhinus semilunaris was studied in three natural lakes in the Marmara Region of NW Turkey using the stable isotopes of δ13C and δ15N. In two of the lakes, the trophic niches (as the isotopic niche) of the gobies were highly divergent with co-existing native fishes, with no overlap. Moreover, mixing models suggests considerable inter-specific dietary differences. In all lakes, the trophic niches of gobies were never significantly larger than those of co-existing fishes. These results suggest that when introduced outside of their natural range, the gobies might integrate into new fish communities via exploiting resources that are underexploited by native fishes or will initially share resources with these species before their niches diverge, perhaps through competitive displacement

Interactions of invasive pumpkinseed with a riverine endemic fish indicate trophic overlap but minimal consequences for somatic growth and condition

The North American invasive fish pumpkinseed Lepomis gibbosus has been associated with some detrimental ecological consequences in some parts of its invasive range. Here, we tested the trophic interactions of pumpkinseed with the endemic stream fish Aegean chub Squalius fellowesii ('chub') in a Mediterranean-type water course in SW Anatolia, Turkey, using a bulk stable isotope approach (d13C, d15N). Seven sampling sites were able to be grouped as chub in pumpkinseed presence (n=2) and absence (n=3), and pumpkinseed in chub absence (n=2). Across these groups, stable isotope metrics revealed that chub trophic (isotopic) niche size was similar in pumpkinseed presence/absence, but pumpkinseed had a larger niche in chub presence. In sites where they are co-habited, their niches showed some convergence, but with no apparent consequences for their growth or body condition, suggesting there were minimal ecological consequences of this sharing of food resources. These results suggest that the trophic consequences of this riverine invasion of pumpkinseed on this endemic chub was minimal

Evidence of threat to European economy and biodiversity following the introduction of an alien pathogen on the fungal–animal boundary

Recent years have seen a global and rapid resurgence of fungal diseases with direct impact on biodiversity and local extinctions of amphibian, coral, or bat populations. Despite similar evidence of population extinction in European fish populations and the associated risk of food aquaculture due to the emerging rosette agent Sphaerothecum destruens, an emerging infectious eukaryotic intracellular pathogen on the fungal–animal boundary, our understanding of current threats remained limited. Long-term monitoring of population decline for the 8-year post-introduction of the fungal pathogen was coupled with seasonal molecular analyses of the 18S rDNA and histological work of native fish species organs. A phylogenetic relationship between the existing EU and US strains using the ribosomal internal transcribed spacer sequences was also carried out. Here, we provide evidence that this emerging parasite has now been introduced via Pseudorasbora parva to sea bass farms, an industry that represents over 400 M€ annually in a Mediterranean region that is already economically vulnerable. We also provide for the first time evidence linking S. destruens to disease and severe declines in International Union for Conservation of Nature threatened European endemic freshwater fishes (i.e. 80% to 90 % mortalities). Our findings are thus of major economic and conservation importance

Development of validated stability-indicating chromatographic method for the determination of fexofenadine hydrochloride and its related impurities in pharmaceutical tablets

A simple reversed phase high performance liquid chromatographic method with diode array detector (HPLC-DAD) has been developed and subsequently validated for the determination of fexofenadine hydrochloride (FEX) and its related compounds; keto fexofenadine (Impurity A), meta isomer of fexofenadine (Impurity B), methyl ester of fexofenadine (Impurity C) in addition to the methyl ester of ketofexofenadine (Impurity D). The separation was based on the use of a Hypersil BDS C-18 analytical column (250 × 4.6 mm, i.d., 5 μm). The mobile phase consisted of a mixture of phosphate buffer containing 0.1 gm% of 1-octane sulphonic acid sodium salt monohydrate and 1% (v/v) of triethylamine, pH 2.7 and methanol (60:40, v/v). The separation was carried out at ambient temperature with a flow rate of 1.5 ml/min. Quantitation was achieved with UV detection at 215 nm using lisinopril as internal standard, with linear calibration curves at concentration ranges 0.1-50 μg/ml for FEX and its related compounds. The optimized conditions were used to develop a stability-indicating HPLC-DAD method for the quantitative determination of FEX and its related compounds in tablet dosage forms. The drugs were subjected to oxidation, hydrolysis, photolysis and heat to apply stress conditions. Complete separation was achieved for the parent compounds and all degradation products. The method was validated according to ICH guidelines in terms of accuracy, precision, robustness, limits of detection and quantitation and other aspects of analytical validation