Resistance to QoI Fungicide and Cytochrome b Diversity in the Hungarian Botrytis cinerea Population

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Magyarországi Botrytis cinerea izolátumok citokróm b génjének diverzitása

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Optimization of Turbine Blade Cooling Using Combined Cooling Techniques

This paper presents analysis and optimization of turbine bade cooling systems. Since the temperature of combustion gases is very high sometimes reaching 2400 K, the turbine blade cannot sustain the resulting thermal stress. Moreover, for higher efficiency for advanced gas turbines, increase of inlet temperature is needed. Common blade cooling methods are film cooling, convection cooling, impingement cooling and combined cooling. In this paper, a numerical solution of the thermal and flow fields in film cooling technique on the AGTB expand symmetrical turbine blade was obtained and the results were validated with experimental data. Then the turbine blade geometry was changed and two combined cooling (impingement/convection cooing and impingement/film cooling) techniques were evaluated. The low Reynolds number k-epsilon turbulence model (AKN) was used for the turbulent flow simulations at various blowing ratios for two blade thicknesses. Comparisons of the results between the available experimental and numerical data showed that the AKN model is capable of predicting the turbulent flow and heat transfer in turbine blade cooling. Combined techniques (impingement/convection cooling and impingement/film cooling) were also carried out and more cooling effectiveness and uniform temperature distribution were found than film cooling method only

Resistance to QoI Fungicide and Cytochrome b Diversity in the Hungarian Botrytis cinerea Population

Quinol oxidation inhibitors (QoIs) are one of the most important classes of fungicides used in agriculture. They block electron transfer between cytochrome b and cytochrome c1, thereby impeding the production of ATP via oxidative phosphorylation. QoI fungicides are generally at high risk of provoking resistance in fungal phytopathogens. Resistance has been reported in more than thirty species, amongst others, in Botrytis cinerea. In various QoI-resistant monosporic B. cinerea isolates from Hungary, a G-to-C point mutation was identified in the mitochondrial gene that encodes the QoI target, cytochrome b, resulting in a glycine to alanine substitution at position 143 (G143A). Analysis of Hungarian group I and group II strains further indicated the frequent occurrence of an additional group I-type intron in the cytb gene directly downstream of the glycine-143 codon. Mutual presence of distinct mitochondrial DNAs specifying different cytb alleles (heteroplasmy) has also been detected in monosporic strains. Remarkably, a number of group II field isolates were found to be highly resistant to azoxystrobin although they did not appear to carry the G-to-C mutation (G143A) generally associated with fungal QoI-resistance

Carthamus, Salvia and Stachys species protect neuronal cells against oxidative stress-induced apoptosis.

Abstract Context: Finding effective therapies for neurodegenerative diseases is of utmost importance for the aging population. Plants growing in Iran are rich sources of antioxidants and active phytochemicals.The protective capacity of plants, with a special focus on those with reported antioxidant or neuroprotective potential or nervous system-related applications in folk medicine, was tested against oxidative stress-induced apoptosis.Aerial parts of 20 plants including Carthamus, Salvia, and Stachys species were extracted with 80\% methanol and dichloromethane and preincubated with neuronal PC12 cells for 3 h. Oxidative stress and apoptosis were induced by hydrogen peroxide (75 µM, 1 h exposure). Cell viability and intracellular reactive oxygen species (ROS) were measured by MTT and 2',7'-dichlorofluorescein-diacetate (DCFH-DA) assays, respectively, while apoptosis was determined by annexin V-FITC/propidium iodide staining by a flow cytometer.Eighty percent methanol extracts of Carthamus oxyacantha Bieb. (Asteraceae), Salvia santolinifolia Boiss. (Lamiaceae), and Salvia sclarea L. (Lamiaceae) at the concentration of 100 μg/ml showed significant neuroprotection in the MTT assay by 38.7, 34.7, and 39.5\%, respectively, and inhibited intracellular ROS by 48.6, 61.9, and 61.4\%, respectively. The first two extracts also significantly inhibited apoptosis. Dichloromethane extracts of C. oxyacantha and Stachys pilifera Benth. (Lamiaceae) at the concentration of 25 μg/ml showed neuroprotection by 27.5 and 26.5\%, respectively, and inhibited ROS by 44.5 and 39.4\%, respectively.The above-mentioned plants seem to have important biological activities and their further study may lead to the discovery of new natural therapeutics useful against disorders such as Alzheimer and Parkinson diseases