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High soil salinity represents a critical environmental constraint to crop production. In order to ameliorate the effects of salinity, a plethora of molecules have been applied and promising outcomes have been noted. The beneficial effects of chitosan (CTS) and melatonin (Mel) application, separately, have been previously recorded with respect to plant growth and productivity, leading to the hypothesis that their conjugation in the form of chitosan-melatonin nanoparticles (CTS-HPMC-Mel NPs) could lead to further enhanced performance of plants under control and stress conditions. In this regard, novel CTS-HPMC-Mel NPs were synthesized, characterized and then employed as a chemical priming agent in spearmint (Mentha spicata L.) plants 24 h prior to salinity stress imposition. As expected, salt stress negatively affected morphophysiological attributes such as plant height, leaf number, leaf fresh weight, leaf dry weight, photosynthetic pigments, Fv/Fo, and Fv/Fm. On the other hand, stress-related attributes, such as content of proline, MDA and H2O2, as well as activity of APX and GP enzymes were increased in response to salt stress. However, adverse effects of salt stress were ameliorated with Mel and CTS-HPMC-Mel NP treatments by enhancing morphological traits, proline, antioxidant enzymatic activities, as well as content of dominant constituents of essential oil profile. It is worth noting that conjugated form of Mel with chitosan, in comparison with solo treatment of Mel, was more effective in combating stress effects. To our knowledge, this is the first report to demonstrate that engineered CTS-HPMC-Mel NPs could be applied as an innovative protective agent to mitigate the effects of salinity in crop plants.

The growth, development, and morphology of plants are extremely affected by many internal and external factors. In this regard, plant nourishing solutions take the most impact. Nowadays, the magnetization of nutrient solutions has been recommended as a promising eco-friendly approach for improving the growth and development of plants. This study was designed to explore the potential of magnetic nutrient solutions in altering morphometric characteristics as well as some physiological and nutritional attributes of Rasha grapevines. Magnetic treatments included magnetized nutrient solution (MagS) and pre-magnetized water completed with nutrients (MagW + S) at magnetic field intensities (0.1 and 0.2 T). According to the results, the most considerable changes in leaf shape and size as well as fresh and dry weights were observed in the plants treated with MagS at 0.2 T. Also, MagS 0.2 had a significant effect on increasing photosynthetic pigments, content of total soluble carbohydrates and protein, and activity of antioxidant enzymes. The content of TNK, K, P, Fe, and Cu was considerably amplified by MagW + S 0.2. Overall, the magnetic solutions had favorable influences on physiological, nutritional state, and leaf morphology of grapevines possibly through alerting water and solution properties, mineral solubility, and phytohormones signalling.

Software-Defined Networking (SDN) is a modern paradigm that provides a platform for implementing reliable, centrally managed, and automated security solutions for conventional and new generation networks, such as IoT, cloud computing, 5G/6G mobile communication networks, and vehicular communications. In these complex systems, manual security operations can delay or obstruct the identification, mitigation, and prevention of ever-increasing sophisticated threats. Thus, the idea of security automation for networks using the SDN paradigm has become fundamental, given that SDN was created to facilitate the operation and management of complex networks with minimal human intervention, which is considered error-prone. This survey studies the state-of-the-art research efforts concerned with security automation in SDN environments. We identified and ranked various classes of security solutions with different levels of automation and complexity. The level of automation is measured using four well-defined qualitative parameters: self-healing, self-adaptation, self-configuration, and self-optimization. The complexity is characterized by the amount of processing and storage resources and implementation requirements. This work represents the first endeavor to analyze the level of automation and complexity of security solutions in SDN environments. Our findings reveal important advances in the area of security automation in SDN. However, there are still several open problems and challenges, which we detail in this work.

Hydroponic systems are used as an instrument to solve a wide range of environmental concerns such as climate change, drought, and soil fertility. Effective growing media are vital to the hydroponically plant cultivation system. Plant reaction to the growing media treated by magnetic fields, as an innovative technology, should be investigated since the magnetic field can constitute a non-toxic and non-residual stimulus. In the current study, some physiological and biochemical responses (leaf fresh and dry weight, biomass, leaf area, plant height, stem diameter, photosynthesis pigments, carbohydrates, protein, and proline contents and peroxidase activity (POD)) and elemental uptake of hydroponically grown grapevines to the magnetic solutions (with 0.1 and 0.2 T intensities) were evaluated. The solutions were magnetized in two ways: 1) solutions magnetized after preparing (S 0.1 and S 0.2), and 2) salts were added to the pre-magnetized waters (W + S 0.1 and W + S 0.2). The results revealed that magnetic treatments had effect on increasing of leaf elements uptake including N+, P+, K+, Ca2+, Fe2+, and Zn2+. Magnetic treatments also stimulated chlorophyll content, leaf extension, leaf fresh and dry weight, and biomass accumulation. Carbohydrates content and POD were promoted in grapes treated by S 0.1 and W + S 0.1 than control. W + S 0.1 and S 0.2 increased the proline and protein content, respectively. The findings proposed that solution magnetization application could act as an elicitor agent to mimic the stress condition, but at the lesser level resulting in activation of grape physiological and biochemical processes and elemental state through stress-related responses.

In this study, a mixed matrix polyethersulfone-based nanofiltration membrane was prepared by incorporation of (cobalt ferrite/activated carbon) composite nanoparticles. The composite nanoparticles were also synthesized using the chemical precipitation technique. The FTIR, XRD and FESEM were used to characterize the synthesized nanoparticles. The fabricated membranes were also studied using SEM, 3D surface image, and water contact angle, mean pore size and porosity measurements. The water flux, salt rejection and antifouling ability of membranes were investigated. The blended membranes showed a more hydrophilic and smoother surface compared to the pristine membrane. The membrane PWF was declined initially using 0.05 wt. % (CoFe2O4/AC) nanoparticles into membrane body and then enhanced by a further increase of nanoparticles’ concentration up to 0.1 wt. % in membrane matrix; PWF was reduced again for the blended membranes at higher concentration of nanoparticles. The NaCl and Na2SO4 rejections were enhanced from (42% to 85%) and (55% to 95%) by the use of (CoFe2O4/AC) nanoparticles into the membrane body. The blended membranes also exhibited appropriate anti-fouling property and more stable flux compared to the pristine membrane. The highest Pb2+, Ni2+, and Cu2+ rejections were found 86%, 90%, and 97%, respectively, for the blended membrane containing of 1 wt. % (CoFe2O4/AC) compared to others.

In the presence of slow diffusion of information, the transmission of idiosyncratic shocks through economically linked firms leaves footprints in the prices. In this paper, we estimate the links between firms using past prices and predict the average shock exerted to each firm in the entire cross-section. The long-short cross-momentum portfolio constructed based on average shocks yields significant alphas and performs well in explaining variation in returns.

Diesel engines are the most commonly used internal-combustion engines. Due to incomplete combustion of fossil fuels, engine performance and emissions output are unsuitable. On the other hand Emissions of greenhouse gases using fossil fuels in internal-combustion engines are considered to be the main cause of climate change. Thus to find an alternative fuel to eliminate or reduce CO2 and exhaust emissions is an urgent concern worldwide. Superabundant and readily available, makes hydrogen an attractive alternative to fossil fuels. In this study, a 3-cylinder turbocharged diesel engine is converted into CNG direct-injection engine and then hydrogen as a fuel enrichment added to CNG. AVL Fire™ Software is used to simulate the engine at different engine speeds, injection pressure, and Air/Fuel ratios. The results confirm that adding hydrogen to CNG improves brake thermal efficiency and engine brake power, reduces brake specific fuel consumption as well as the diminution in HC and Soot but also increases the NOx.

Engine performance parameters, including fuel conversion efficiency (FCE), power, torque and specific fuel consumption (SFC), can be affected by variables such as ignition timing (IGT), injection timing (IT) and hydrogen volume fraction (H2%). In this paper an engine fueled with different H2/CNG blend rations from 0 to 50% volume under ignition and injection timing at different speeds were investigated. For model validation, the engine operating conditions were simulated using the AVL fire software and compared with experimental results. The statistical comparison showed that there was no significant difference between them. Also, a support vector machine (SVM) was used to study the engine's behavior according to the variables studied. The SVM model predicted the FCE, power, torque, SFC and CO with error of less than 4%. The Genetic Algorithm (GA) was used to find optimal IGT, IT and H2% values to achieve optimum engine performance. Therefore, the results showed that the optimum engine operating conditions depend on the engine speed. Also, the results showed that independent variables (IT, IGT and H2%) maximize the engine performance and minimize SFC and CO emission. So that the optimum use of hydrogen in this research at different engine speeds was between 20% and 30%.

In this study, mixed matrix polyethersulfone based nanofiltration membranes were prepared by composite CoFe2O4/CuO nanoparticles. The CoFe2O4/CuO nanoparticles were synthesized by a chemical precipitation technique, and then characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Then, the effect of embedded CoFe2O4/CuO nanoparticles into PES based NF membrane on its physico/chemical properties, separation performance and antifouling ability was studied. The atomic force microscopy (AFM), scanning electron microscopy (SEM), water contact angle, pure water flux, salt rejection, antifouling ability, as well as heavy metal ions separation were used in membrane characterization. The blended membranes with CoFe2O4/CuO exhibited higher surface hydrophilicity and smoother surface than the bare membrane. The water contact angle and average surface roughness reduced from (70° to 35°) and (45 nm to 24 nm) for the bare PES membrane and blended [PES-0.5 wt% CoFe2O4/CuO] membrane, respectively. The PWF measured 34.5 (L/m2 h) for the blended [PES-0.5 wt% CoFe2O4/CuO] membrane and 12 (L/m2 h) for the bare ones. The NaCl and Na2SO4 rejection were increased from (32% to 72%) and (62% to 95%) by introducing CoFe2O4/CuO into the PES matrix. The FRR measured ∼42% for bare membrane whereas that was ∼90% for the superior blended membrane with 0.5 wt% CoFe2O4/CuO nanoparticles. The Cu2+, Ni2+ and Pb2+ rejection measured 98%, 92% and 88% for the blended [PES-0.5 wt% CoFe2O4/CuO] membrane whereas they were 85%, 80% and 78% for the pristine PES membrane. The reusability study for the superior blended membrane showed a slight decrease in average performance less than 4.9%.