Analysis of the phenotypic variability of twenty f3 biparental populations of bread wheat (Triticum aestivum L.) evaluated under semi-arid environment

This research was conducted to screen and analyse the variability within twenty F3 populations of bread wheat (Triticum aestivum L.) generated by Line x Tester mating design. The results indicated the presence of sufficient variability within and between F3 populations for the eight measured variables, which represent plant phenology, physiology, yield and yield components. Different populations have been identified to improve the measured variables separately. The number of spikes appeared to be the most important determinant of grain yield. PCA and cluster analyses indicated that the Acsad1069/El Wifak and Acsad1135/Hidhab, with a relatively high grain yield,  aboveground biomass and 1000 grains weight, are the best F3 populations to improve the productivity. However, Acsad899/Rmada and Acsad1135/Rmada populations were earlier and had a low number of spikes. These populations had also favorable genes for heat tolerance.Keywords: Triticum aestivum L.; Variability; Selection; Tolerance; Yield

Chronic Exposure to the Herbicide, Atrazine, Causes Mitochondrial Dysfunction and Insulin Resistance

There is an apparent overlap between areas in the USA where the herbicide, atrazine (ATZ), is heavily used and obesity-prevalence maps of people with a BMI over 30. Given that herbicides act on photosystem II of the thylakoid membrane of chloroplasts, which have a functional structure similar to mitochondria, we investigated whether chronic exposure to low concentrations of ATZ might cause obesity or insulin resistance by damaging mitochondrial function. Sprague-Dawley rats (n = 48) were treated for 5 months with low concentrations (30 or 300 µg kg−1 day−1) of ATZ provided in drinking water. One group of animals was fed a regular diet for the entire period, and another group of animals was fed a high-fat diet (40% fat) for 2 months after 3 months of regular diet. Various parameters of insulin resistance were measured. Morphology and functional activities of mitochondria were evaluated in tissues of ATZ-exposed animals and in isolated mitochondria. Chronic administration of ATZ decreased basal metabolic rate, and increased body weight, intra-abdominal fat and insulin resistance without changing food intake or physical activity level. A high-fat diet further exacerbated insulin resistance and obesity. Mitochondria in skeletal muscle and liver of ATZ-treated rats were swollen with disrupted cristae. ATZ blocked the activities of oxidative phosphorylation complexes I and III, resulting in decreased oxygen consumption. It also suppressed the insulin-mediated phosphorylation of Akt. These results suggest that long-term exposure to the herbicide ATZ might contribute to the development of insulin resistance and obesity, particularly where a high-fat diet is prevalent

Noise spectra of K+ and NH4+ ions at over-limiting current in an electrochemical system with a cation exchange membrane

The present work investigates the effect of the counter ion nature on the noise of the over-limiting current (Iov). Moreover, the electrochemical methods, current voltage curve (I-V) and the chronopotentiometry (V-t) measurements are applied. The over-limiting current is always accompanied by a neat electrical noise. It is a well accepted experimental phenomenon. The study of this noise may contribute to a better understanding of the Iov and the feasibility of electrodialysis operation at this current in terms of energy consumption. The electrical noise depends directly on the counter ion nature. The power spectral density of the membrane's potential fluctuation was obtained via Fourier analysis of the time series recorded during the transport of counter ions (K+ and NH4+). The spectra are evaluated above the limiting current indicating the differences between the K+ and the NH4+. It is found that the cation NH4+ presents a singular behaviour and the noise is minimal

Stability analysis for grain yield and thousand kernel weight of durum wheat (Triticum durum Desf.) genotypes growing under semi-arid conditions

Abstract. The present study was carried out to select adapted and stable durum wheat (Triticum durum Desf.) genotypes for grain yield and thousand kernel weight using various stability parameters. Based on the graphical distributions between the parametric indices (Wricke’s ecovalence stability index (Wi²), environmental coefficient of variance (CVi), mean variance component (θi )) and the mean grain yield of tested genotypes, the suitable genotype for the tested conditions was Mexicali 75. Further, the cultivars Oued Zenati and Bousselem were the most adapted with the highest TKW. With non-parametric index was classified genotype Mexicali 75 as the most stable with high grain yield. According to PCA analysis the genotype Altar 84 was classified in dynamic stability group with the highest grain yield in addition, cultivars Bousselem and Oued Zenati were classified in dynamic concept with the highest thousand kernel weight. The results of this study confirmed that the parametric and non-parametric methods are the suitable tools to identify the most stable durum wheat (Triticum durum Desf.) under semi-arid conditions

Electrochemical study of penicillin-G as a corrosion inhibitor for Fe-19Cr stainless steel in hydrochloric acid

In the present work, the inhibitory properties and the adsorption mechanism of penicillin G for the corrosion of Fe-19Cr stainless steel in an HCl solution were investigated. Electrochemical methods, the open circuit potential (OCP) and the current potential curves (I-V) were used. The inhibition efficiency of the penicillin G was calculated and found to be up to 60% for hydrochloric acid. The adsorption of this inhibitor was described by Langmuir isotherm, and the negative values of Gibbs energy indicate the nature of interactions between the inhibitor molecules and the metal surface. © 2017, Sociedade Portuguesa de Electroquimica. All rights reserved

Total polarization effect on the location of maximum temperature value in planar SOFC

The aim of the present study is the evaluation and the location of the maximum temperature values within the solid and porous components of a planar SOFC under the effect of total polarization: Ohmic, activation, concentration and the chemical reaction. The temperature field in SOFC components (interconnection, cathode, anode and electrolyte) is obtained by developing a mathematical model in FORTRAN language. The mathematical model predictions show the effect of the overpotentials on the thermal gradient and its locations in an SOFC with two geometries: i) anode or ii) electrolyte supported. The results are also discussed, following the SOFC low or high operating temperatures. Copyright (C) 2010, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved