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The fish assemblages of the Eastern Mediterranean are highly variable owing to the Lessepsian migration. So far, there has been limited discussion about the temporal variation of Lessepsian populations, which may be a key to better understanding the establishment, persistence and spreading dynamics of these species. The objective of this study was, therefore, to develop an understanding of inter‐annual variations of Lessepsian fish populations through investigating the effects of climate conditions. For this purpose, we evaluated the data obtained from the seasonal bottom trawl surveys conducted over the course of 12 years, from 2004 to 2015, at the infra‐littoral zone of Iskenderun Bay. Our results indicated that Lessepsians constituted 27%, 62% and 85% of total teleost fishes in the number of species (LS‐%), biomass (LW‐%) and abundance (LN‐%), respectively. The linear trends showed that the dominance of Lessepsian fishes increased with annual rates of 1.9 (p < .01, LS‐%), 2.77 (p < .01, LW‐%) and 1.43% (p < .05, LN‐%) per year during the study period. In contrast, seasonal trend decomposition based on GAMMs revealed that the true shape of trends was non‐linear. The majority of the new Lessepsians entered the study area after 2009 when warmer conditions prevailed. Those new invaders such as Nemipterus randalli, Pomadasys stridens and Apogon smithi successfully settled in a short time and remarkably altered the composition of fish assemblages after 2010. We found that variations of lessepsian fish assemblages were correlated with the increase of annual minima and average values of sea surface temperature.  相似文献   
2.
Water, Air, &; Soil Pollution - Lake E?irdir is one of the most important freshwater resources in Turkey. The lake is located at the border of Isparta province in South West Turkey, an area...  相似文献   
3.
Towards the end of the 1980s, when the spawning grounds in the northwestern shelf (NWS) of the Black Sea were lingering with the effects of eutrophication and of an exotic invasive ctenophore, a series of basin‐wide international ichthyoplankton surveys pointed out an increase in the anchovies spawning in the southern half of the Black Sea. Later, with the help of international conservation efforts, several key littoral ecosystem components within the anchovy's historical spawning grounds showed signs of recovery. However, the fate of the spawning stock anchovy in the south remained unanswered. In order to present the current situation in the southern Black Sea after two decades, an ichthyoplankton survey adopting the same methodology as previously used was undertaken during the peak spawning season of the Black Sea anchovy (BSa). The survey showed that the density of eggs was by far greater than for any of the surveys conducted previously. A wider geographical distribution of the eggs indicated an increase in the number of vagrants which had drifted away from the known spawning grounds. In contrast, the increased reproductive activity in the south signifies existence of a growing, non‐migrating southern BS stock. This stock seems to utilize the coastal hydrographic features associated with the rim current facilitating escape (loophole) from gelatinous predators such as Mnemiopsis leidyi and Aurelia aurata.  相似文献   
4.
Grapevine leaves are consumed as a food in Mediterranean countries. At the same time, it is a byproduct of the wine industry. Antioxidant, antihypertensive and antidiabetic properties of grapevine leaves after ultrasound-assisted extraction (UAE), microwave assisted extraction (MAE) and classical solvent extraction (CSE) were evaluated and compared by using water and methanol as solvent. DPPH radical scavenging activity, total phenolic content (TPC), total antioxidant capacity (TEAC), metal chelating activity, ACE inhibitory activity and α?glucosidase inhibitory activity of grapevine leaves extracts were determined. The highest values of grapevine leave extracts for antioxidant properties; DPPH (61.60%), TPC (910.18?mg GAE?g?1), TEAC (6.23?µg Trolox mg?1) and metal chelating activity (IC50; 3.18?mg mL?1) were obtained from UAE when the methanol was used extracting solvent. However antihypertensive activity (13.68%) and antidiabetic activity (83.00%) values obtained from MAE by using water as a solvent were relatively highest. The effectiveness of UAE, MAE and CSE methods in terms of antioxidant, antihypertensive and antidiabetic properties of grapevine leaves were significantly (p?<?0.05) different from each other. This differences depending on the solvent used.  相似文献   
5.
Methyl parathion is an organophosphate insecticide that has been used in agriculture and domestic for several years. Vitamin C (200 mg/kg bw per day) + vitamin E (200 mg/kg bw per day), methyl parathion (0.28 mg/kg bw per day) and vitamin C (200 mg/kg bw per day) + vitamin E (200 mg/kg bw per day) + methyl parathion (0.28 mg/kg bw per day) combination were given to rats orally via gavage for 7 weeks. Body and testis weights, sperm counts, sperm motility, sperm morphology and histopathological changes in the testes were investigated at the end of 24 h, 4th and 7th weeks comparatively with control group. No pathological changes were observed in all parameters at the end of 24 h. When methyl parathion-treated group and vitamins C and E + methyl parathion-treated group were compared to control group, body and testis weights decreased significantly at the end of 4th and 7th weeks. It was observed that, at the end of 4th and 7th weeks there was a statistically significant decrease in sperm counts and sperm motility, increase in abnormal sperm morphology when methyl parathion- and vitamins C and E + methyl parathion-treated group were compared to control group. While sperm counts increased at the end of 4th and 7th weeks, sperm motility increased at the end of 7th week when vitamins C and E + methyl parathion-treated group compared with methyl parathion-treated group, no changes were observed in abnormal sperm morphology at the end of 4th and 7th weeks. In our light microscopic investigations, after 4 and 7 weeks of methyl parathion exposure, necrosis and edema were observed in the seminiferous tubules and interstitial tissues. After 4 and 7 weeks of vitamins C and E + methyl parathion exposure, degenerative changes were detected in the seminiferous tubules while no pathological findings were observed in the interstitial tissues. According to the present study, we conclude that vitamins C and E reduces methyl parathion testicular toxicity, but it does not protect completely.  相似文献   
6.
Graft copolymerization of acrylamide onto commercial acrylic fibers was carried out using benzoyl peroxide as a free-radical initiator in aqueous medium within the 75–95 °C temperature range. In this study, the effects of initiator and monomer concentration, the amount of fiber, polymerization time, and temperature on the graft yield were investigated. The optimum concentration for initiator was found to be 2.0×10−3 mol/l and the optimum temperature of 85 °C. The activation energy of the reaction was calculated to as 35.81 kJ/mol at the temperature interval of 75–95 °C. The structures and morphologies characterization of grafted fibers was investigated by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The thermogravimetric analysis data showed that the thermal stability of the acrylic fibers increased with graft yield. The scanning electron photographs showed that the homogeneous appearance of the fiber surface changed and a shell-like heterogeneous structure occurred at the surface with an increasing degree of grafting. The moisture content, water absorption, dyeability, and antimicrobial activity of grafted acrylic fibers were also reported. The results showed that grafting of polyAAm improved the moisture contain, water absorption, dyeability, and antimicrobial activity of fiber.  相似文献   
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8.
This study evaluated the inhibitory effects of plant-based extracts (grape seed, green tea, and white tea) and their constituent flavan-3-ol monomers (catechins) on α-amylase and α-glucosidase activity, two key glucosidases required for starch digestion in humans. To evaluate the relative potency of extracts and catechins, their concentrations required for 50 and 90% inhibition of enzyme activity were determined and compared to the widely used pharmacological glucosidase inhibitor, acarbose. Maximum enzyme inhibition was used to assess relative inhibitory efficacy. Results showed that grape seed extract strongly inhibited both α-amylase and α-glucosidase activity, with equal and much higher potency, respectively, than acarbose. Whereas tea extracts and catechin 3-gallates were less effective inhibitors of α-amylase, they were potent inhibitors of α-glucosidase. Nongallated catechins were ineffective. The data show that plant extracts containing catechin 3-gallates, in particular epigallocatechin gallate, are potent inhibitors of α-glucosidase activity and suggest that procyanidins in grape seed extract strongly inhibit α-amylase activity.  相似文献   
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