Effect of drought stress on yield, proline and chlorophyll contents in three chickpea cultivars

Drought stress is one of the major abiotic stresses in agriculture worldwide. This study was carried out to investigate the effect of drought stress on proline content, chlorophyll content, photosynthesis and transpiration, stomatal conductance and yield characteristics in three varieties of chickpea (drought tolerant Bivaniej and ILC482 and drought sensitive Pirouz). A field experiment with four irrigation regimes was carried out in a randomized complete block design with three replications. Treatments included control (no drought),drought stress imposed during the vegetative phase, drought stress imposed during anthesis and drought stress during the vegetative phase and during anthesis. All physiological parameters were affected by drought stress. Drought stress imposed during vegetative growth or anthesis significantly decreased chlorophyll a, chlorophyll b and total chlorophyll content. Proline accumulation was higher in ‘ILC482’ than in ‘Pirouz’ both under control and drought stress conditions. Photosynthesis, transpiration, stomatal conductance and yield were higher but sub-stomatal CO2 concentration was lower under drought stress conditions than under control conditions. The results showed that mesophyll resistance is the basic determinate of rate of phototosynthesis under drought stress conditions. Under drought conditions the drought tolerant variety ‘Bivaniej’ gave the highest yield whereas the drought sensitive variety ‘Pirouz’ gave the lowest yield. Drought stress at anthesis phase reduced seed yield more severe than that on vegetative stag

Effect of drought stress and subsequent recovery on protein, carbohydrate contents, catalase and peroxidase activities in three chickpea (Cicer arietinum) cultivars

Drought stress is one of the major abiotic stresses in agriculture worldwide. This study was carried out to investigate the effects of drought stress and subsequent recovery on protein, carbohydrate content, catalase (CAT), and peroxidase (POX) activities in three varieties of chickpea (drought tolerant Bivaniej and ILC482 and drought sensitive Pirouz). A field experiment with four irrigation regimes was carried out in a randomized complete block design with three replications. Treatments included control (well-watering), drought stress imposed during the vegetative phase, drought stress imposed during anthesis and drought stress during the vegetative phase and anthesis. Drought stress imposed during vegetative growth or anthesis significantly decreased soluble protein content and increased water soluble carbohydrate concentration. The tolerant variety accumulated more soluble carbohydrate than the sensitive one. Drought stress at flowering stage had significantly higher POX activity compared to than that at vegetative stage. Compared with the stress, there was significantly more soluble protein after exposure to recovery conditions but POX decreased in all three varieties. These results suggest that CAT and POX activities play an essential protective role against drought stress in chickpea. Antioxidants act as a major defense against radical mediated toxicity by protecting the damages caused by free radicals. An increase was observed in POX and CAT activity of three cultivars under stress conditions throughout the experiment. Results showed that POX acts as the major antioxidant enzyme in chickpea leaves under oxidative stress condition. So activity of this enzyme in stress condition can be used as an index for chickpea cultivars tolerance assessment

Economic and productivity evaluation of different horizontal drilling scenarios: Middle East oil fields as case study

Development of high-density oil and gas fields presents a great challenge to the energy industry due to the low productivity of individual wells and their high drilling cost. We thus compared the productivity, associated costs and economical revenues gained from two field development scenarios, with multilateral and horizontal drilling, to evaluate the optimal drilling and completion conditions in a giant heavy oil reservoir in the Middle East. Well path design was identified as one of the most complex parameters depending on the well-testing results, field production and reservoir simulation data. The fishbone well of four branches with a length of 300 m each and 30° deviation from the main hole was identified to be drilled and completed using open-hole sidetrack as the best approach. The fishbone structure raised production by 393%, while drilling cost only increased by 130% compared with a conventional horizontal well

Smart Contracts in the 5G Roaming Architecture: The Fusion of Blockchain with 5G Networks.

The rollout of fifth generation (5G) cellular network technology has generated a new surge of interest in the potential of blockchain to automate various use cases involving cellular networks. 5G is indeed expected to offer new market opportunities for small and large enterprises alike. In this article, we introduce a new roaming network architecture for 5G based on a permissioned blockchain platform with smart contracts. The proposed solution improves the visibility for mobile network operators of their subscribers\u2019 activities in the visited network, as well as enabling quick payment reconciliation and reducing fraudulent transactions. The article further reports on the methodology and architecture of the proposed blockchain-based roaming solution using the Hyperledger platform

Silicon metasurfaces with tunable electromagnetic resonances for nonlinear optical conversion

Dielectric metasurfaces sustain electromagnetic modes which can be exploited to enhance nonlinear frequency-conversion processes such as thirdharmonic generation. In this work we employ electron-beam lithography to fabricate silicon metasurfaces supporting electromagnetic resonances with different quality factors (Q), ruled by the geometry. This allows to investigate the trade-off between resonant enhancement and matching the spectral bandwidth of the ultrafast excitation source. Both experiments and simulations indicate that higher values of Q do not a priori bring about a stronger third-harmonic generation, which correlates to the spectral overlap between the metasurface resonance and the pump bandwidth

EFFECT OF ANNEALING TEMPERATURE ON THE OPTICAL AND STRUCTURAL PROPERTIES OF DIP-COATED Al2O3 THIN FILMS PREPARED BY SOL–GEL ROUTE

Thin films of Al2O3 were prepared by the sol–gel process. Dip-coating technique was used for deposition of the Al2O3 thin films onto glass substrates. Optical and structural properties of the films were investigated with respect to the annealing temperature (100–500°C). The structure of these films was determined by X-ray diffraction (XRD). Scanning electron microscopy (SEM) was performed for the analysis of surface morphology. For determination of the optical constants of Al2O3 thin films, UV-Visible spectrophotometry measurements were carried out. Annealing temperature affects the structural and optical properties of the Al2O3 thin films. The refractive index and extinction coefficient of the films at 550 nm wavelength increase from 1.56 to 1.66, and from 3.41 × 10-5 to 5.54 × 10-5, respectively while optical band gap and thickness of the films decrease from 4.15 eV to 4.11 eV, and 360 nm to 260 nm, respectively, by increasing annealing temperature from 100°C to 500°C.Aluminum oxide, sol–gel, thin films, optical constants