Physio-Biochemical and agronomic responses of Faba Beans to exogenously applied Nano-Silicon under drought stress conditions

Nano-silicon application is an efficient novel approach to mitigate the deleterious impacts of drought stress on field crops, which is expected to increase owing to climate change, especially in arid regions. Two-season field studies investigated the influence of foliar-applied nano-silicon (0.5, 1, and 1.5 mM) on physiological and biochemical attributes and their impacts on crop water productivity (CWP) and the agronomic traits of faba beans (Vicia faba). The plants were evaluated under two irrigation regimes: well-watered (100% ETc giving 406 mm ha−1) and drought stress (65% ETc giving 264 mm ha−1). It was found that drought stress significantly decreased gas exchange (leaf net photosynthetic rate, stomatal conductance, and rate of transpiration), water relations (relative water content and membrane stability index), nutrient uptake (N, P, K+, and Ca+2), flavonoids, and phenolic content. In contrast, drought stress significantly increased oxidative stress (H2O2 and O⋅−2) and enzymatic and non-enzymatic antioxidant activities compared with the well-watered treatment. These influences of drought stress were negatively reflected in seed yield-related traits and CWP. However, foliar treatment with nano-silicon, particularly with 1.5 mM, limited the devastating impact of drought stress and markedly enhanced all the aforementioned parameters. Therefore, exogenously applied nano-silicon could be used to improve the CWP and seed and biological yields of faba bean plants under conditions with low water availability in arid environments

Preparation, characterization, in vitro drug release and anti-inflammatory of thymoquinone-loaded chitosan nanocomposite

In this study, we formulated Thymoquinone-loaded nanocomposites (TQ-NCs) using high-pressure homogenizer without sodium tripolyphosphate. The TQ-NCs were characterized and their anti-inflammatory determined by the response of the LPS-stimulated macrophage RAW 264.7 cells in the production of nitric oxide, prostaglandin E2, tumor necrosis factor-α, interleukin-6, and interleukin-1β. The physicochemical properties of TQ-NC were determined using different machines. TQ was fully incorporated in the highly thermal stable nanoparticles. The nanoparticles showed rapid release of TQ in the acidic medium of the gastric juice. In medium of pH 6.8, TQ-NC exhibited sustained release of TQ over a period of 100 h. The results suggest that TQ-NC nanoparticles have potential application as parenterally administered therapeutic compound. TQ-NC effectively reduce production of inflammatory cytokines by the LPS-stimulated RAW 264.7 cells, indicating that they have anti-inflammatory properties. In conclusion, TQ-NC nanoparticles have the characteristics of efficient carrier for TQ and an effective anti-inflammatory therapeutic compound.The publication of this article was funded by the Qatar National Library

Cohort Profile: COVIDMENT: COVID-19 cohorts on mental health across six nations

Why were the cohorts set up? With more than 218 million cases and 4.5 million deaths worldwide (Worldometers, 31 August 2021), the COVID-19 pandemic has had an unprecedented influence on the global economy and population health. As a potent global disaster, it is likely to significantly affect the incidence of adverse mental health symptoms and psychiatric disorders, particularly in vulnerable and highly affected populations. The World Health Organization and leading scientific journals have alerted concerning the potential adverse mental health impact of COVID-19 and emphasized the need for multinational research in this area, which additionally provides new insights into disease mechanisms

Synthesis and characterization of polyurethane coatings based on soybean oil–polyester polyols

Soybean oil was esterified by glycerol (1:3) molar ratio to produce monoglycerides, and then reacted with phthalic anhydride at ratios 20%, 40% and 60% to produce polyester polyols denoted by PES20, PES40 and PES60. They were investigated by IR spectra and solubility in methanol. Diphenylmethane diisocyanate was reacted with these polyols at NCO/OH ratios 1.2, 1.4, 1.6 using toluene as a solvent to produce polyester–polyurethane coatings, which were characterized by IR spectra. The prepared coatings were characterized by flexibility, pencil hardness, impact resistance and chemical resistance. Good properties of the prepared coatings increase in the direction of increasing hard segments in the sample

Modeling growth, carbon allocation and nutrient budgets of Phragmites australis in Lake Burullus, Egypt

Phragmites australis is the major component of reed stands covering some 8200 ha along the shores of Lake Burullus (Egypt). We applied a published temperate zone reed model to assess growth and cycling of C and nutrients among the various organs of P. australis in this sub-tropical lake. We aim to quantify the role of reed stands for the C balance and nutrients cycling in the south Mediterranean wetland. Above-ground biomass was 3.5 times higher than the below-ground biomass. Root biomass represented 13% of the total below-ground, while leaves and panicles represented 16 and 3% of the above-ground biomass, respectively. Remobilization from rhizomes (15%) and reallocation from leaves (1%) were of little importance as assimilated sources. Nutrients accumulation by total above-ground biomass ranged between 2.7 to 46.8 g m−2 yr−1 for P and K, respectively. We calculated a C sequestration rate of 38.4 g C m−2 yr−1 for the dead rhizomes in the sediments. This value stresses the importance of P. australis stands for C sequestration in Lake Burullus. Further, as much as 254 t P and 5527 t N could potentially be removed annually from Lake Burullus by harvesting P. australis at maximum total above-ground biomass.

Evaluation of carbon stock in the sediment of two mangrove species, Avicennia marina and Rhizophora mucronata, growing in the Farasan Islands, Saudi Arabia

The aim of this study was to conduct the first comprehensive evaluation of carbon stock in the sediments of Avicennia marina (black mangrove) and Rhizophora mucronata (red mangrove) along the coastline of an arid region (Farasan Islands, Saudi Arabia). Such information is necessary for the development of any management plan for the mangrove ecosystems along the Saudi Red Sea islands and provide a rationale for the restoration of mangrove forests in Saudi Arabia. A. marina and R. mucronata locations showed significant (P < 0.001) differences in sediment bulk density (SBD) and sediment organic carbon (SOC) concentration with higher mean values for both in the sediments of A. marina. Considering the whole depth of sediment sampled (0–50 cm), the highest value of SOC stock (12.3 kg C m−2) was recorded at A. marina locations and the lowest (10.8 kg C m−2) at R. mucronata locations. Thus, the SOC stock of A. marina was greater than that of R. mucronata by 114.3%. Consequently, considering the rate of carbon sequestration and the area of mangrove forests (216.4 ha), the total carbon sequestration potential of mangroves in the Farasan Islands ranged between 10.3 Mg C yr−1 and 11.8 Mg C yr−1 for R. mucronata and A. marina locations, respectively. Thus, it is necessary to protect and restore these ecosystems for the sequestration of carbon and for their other valuable ecosystem services