An experiment was conducted at Malakabad (Gadera) Dargai Malak and KPK to study the effect of different levels of nitrogen and phosphorus on the yield of maize varieties in randomize complete block design with split plot arrangement.

Rice crop is highly susceptible to the toxic levels of lead (Pb) during early growth stages. Moreover, a sufficient availability of mineral nutrients is critical for survival of plants particularly under stressful conditions. An experiment was carried out to unravel the coordinated effects of Pb stress (1-mM PbCl) and different nutrient treatments (sufficient nutrient supply, nitrogen (N) deprivation, phosphorus (P) deprivation, and potassium (K) deprivation) on morphological growth, reactive oxygen species (ROS), antioxidants, and nutrient status in primed and non-primed rice seedlings. Seeding were primed with distilled water, 60-μM selenium, or 100-mg L salicylic acid. Results indicated that Pb toxicity did not affect the root growth, but severely reduced the shoot growth (length and biomass) of rice in N- or P-deprived seedlings. Rice seedlings grown with sufficient supply of nutrients or K-deprivation showed no growth reduction under Pb toxicity. Exposure of Pb stress triggered the production of ROS (HO, O˙, OH) and lipid peroxidation rate particularly under N- or P-deprivation. Moreover, the shoot accumulations of macronutrients (P in particular) were also restricted under Pb toxicity. Seed priming treatments effectively alleviated the undesirable effects of Pb stress on rice growth. The primed rice seedlings showed minimal oxidative damage caused by excessive generation of ROS under Pb stress and/or nutrient deprivation. Seed priming strengthened the antioxidative defense system of rice seedlings by regulating the activities/levels of superoxide dismutase, catalase, peroxidase, and glutathione in rice leaves. Moreover, better accumulation of essential nutrients in primed rice seedlings prevented the excess uptake and translocation of Pb, as evident by the lowered shoot accumulation of Pb.

No abstract

We investigated double perovskite compounds of the form Sr 2 XOsO 6 (X = Li, Na, Ca) using the fullpotential linearized augmented plane wave (FP-LAPW) method. For the exchange-correlation energy, Wu and Cohen generalized gradient approximation (WC-GGA), Perdew, Burke and Ernzerhof GGA (PBE-GGA), Engel and Vosko GGA (EV-GGA), and GGA plus Hubbard U-parameter (GGA + U) were used. The calculated structural parameters are in good agreement with the existing experimental results. Calculation of different elastic constants and elastic moduli reveals that these compounds are elastically stable and possess ductile nature. The GGA + U approach yields quite accurate results of the bandgap as compared with the simple GGA schemes. The density of states plot shows that Sr-4d, Os-5d and O-2p states predominantly contribute to the conduction and valence bands. Further, our results regarding to the magnetic properties of these compounds reveal their ferromagnetic nature. In addition, these compounds seem to possess half-metallic properties, making them useful candidates for applications in spintronics devices.

This study shows that the resolution of a digital elevation model (DEM) and model mesh strongly influences 3D simulations of seismic response. Topographic heterogeneity scatters seismic waves and causes variation in seismic response (amplification and deamplification of seismic amplitudes) at the Earth's surface. DEM resolution influences the accuracy and detail with which the Earth's surface can be represented and hence affects seismic simulation studies. Apart from the spatial resolution of a DEM, the mesh resolution, adopted in the creation of a 3D spectral element meshing, also changes the detailedness of surface topography. Working with high-resolution data is in most cases not possible on a regional scale because of its costliness in terms of time, money, and computation. In this study, we evaluate how low the resolution of DEM and mesh can become before the results are significantly affected. We simulated models with different combinations of DEM and mesh resolutions. The peak ground displacement (PGD) obtained from these simulations was compared with the PGD of the model with the finest mesh and DEM resolution. Our results show that any mesh or DEM resolution of 540 m or coarser will give unrealistic results. These results are valid for similar terrains as studied here and might not be directly applicable to regions with significantly different topography.