Polluting resource extraction and climate risk

Using a fossil fuel extraction model that treats the atmosphere as a depletable resource, we study the optimal price of carbon in the presence of endogenous uncertainty around a climatic regime shift. We find that the optimal carbon tax should account an uncertainty-adjusted cost term associated with the environment's scarcity. This term is shown to be sensitive to the natural sequestration rate of the atmosphere and to the probability surrounding a climate tail event. Our analysis also shows that in the presence of uncertainty, the shadow price of the environment should grow at a faster rate. Lastly, compared to the endogenous uncertainty case, we find that if the probability surrounding a regime shift is exogenously given, this shadow price should even grow at a higher rate.     

Proximate Composition,Bioactive Compounds,and Antioxidant Potential of Wild Halophytes Grown in Coastal Salt Marsh Habitats

Halophytes have been characterized as a potential resource for fiber, food, fodder, and bioactive compounds. Proximate composition, bioactive compounds, and antioxidant activity of five wild dominant halophytes (Arthrocnemum macrostachyum, Halocnemum strobilaceum, Limoniastrum monopetalum, Limoniastrum pruinosum, and Tamarix nilotica) naturally growing along the Nile Delta coast were assessed. The soil supporting these halophytes was sandy to sand-silty, alkaline, with low organic carbon, and relatively high CaCO₃. H. strobilaceum attained the highest moisture content, ash, crude fiber, lipids, and total soluble sugars. L. monopetalum showed the highest content of crude protein (18.00%), while T. nilotica had the highest content of total carbohydrates. The studied halophytes can be ranked according to their nutritive value as follows: H. strobilaceum > L. monopetalum > A. macrostachyum > L. pruinosum > T. nilotica. A. macrostachyum attained the highest amount of Na⁺, K⁺, Ca²⁺, and Mg²⁺. A. macrostachyum showed a high content of phenolic compounds, while H. strobilaceum was rich in tannins and saponin contents. The MeOH extract of A. macrostachyum and H. strobilaceum exhibited substantial antioxidant activity. The present results showed that the studied halophytes could be considered as candidates for forage production or used as green eco-friendly natural resources for bioactive compounds.     

Design and synthesis of some novel quinoline derivatives as anticancer and radiosensitizing agents targeting VEGFR tyrosine kinase

Quinoline derivatives posses many types of biological activities and have been reported to show significant anticancer activity. There is a variety of mechanisms for the anticancer activity and the most distinguished mechanism is the inhibition of vascular epithelial growth factor receptor tyrosine kinase (VEGFRTK). Novel quinoline derivatives 6 , 7a , 7b , 7c , 8 , 9 , 10 , 11 , 12 and pyrimido[4,5‐b]quinoline derivatives 16 , 17 , 18 , 19 , 20 are reported herein. All the newly synthesized compounds were evaluated for their in vitro anticancer activity against human breast cancer cell line (MCF7) in which VEGFR is highly expressed. Compounds 6 and 7 with IC₅₀ values of 8.5 μM and 21.9 μM were the most active compounds and exhibited cytotoxic activities higher than that of the reference drug doxorubicin (IC₅₀= 32.02 μM). The most active compounds 6 and 7 were further evaluated for their ability to enhance the cell killing effect of γ‐radiation. J. Heterocyclic Chem., (2011).     

802GHz integrated horn antennas imaging array

This short paper presents the pattern measurements at 802GHz of a single element in a 256-element integrated horn imaging array. The integrated-horn antenna consists of a dipole-antenna suspended on a 1m dielectric membrane inside a pyramidal cavity etched in Silicon. The theoretical far-field patterns, calculated using reciprocity and Floquet-modes representation of the free-space field, agree well with the measured far-field patterns at 802GBz. The associated directivity for a 1.40 horn aperture, calculated from the measured E and H-plane patterns is 12.3dB±0.2dB. This work demonstrates that high-efficiency integrated-horn antennas are easily scalable to terahertz frequencies and could be used for radio-astronomical and plasma-diagnostic applications.     

Synthesis of Robust MOFs@COFs Porous Hybrid Materials via an Aza-Diels–Alder Reaction: Towards High-Performance Supercapacitor Materials

Metal–organic frameworks (MOFs) and covalent organic frameworks (COFs) have attracted enormous attention in recent years. Recently, MOF@COF are emerging as hybrid architectures combining the unique features of the individual components to enable the generation of materials displaying novel physicochemical properties. Herein we report an unprecedented use of aza-Diels–Alder cycloaddition reaction as post-synthetic modification of MOF@COF-LZU1, to generate aza-MOFs@COFs hybrid porous materials with extended π-delocalization. A a proof-of-concept, the obtained aza-MOFs@COFs is used as electrode in supercapacitors displaying specific capacitance of 20.35 μF cm⁻² and high volumetric energy density of 1.16 F cm⁻³. Our approach of post-synthetic modification of MOFs@COFs hybrids implement rational design for the synthesis of functional porous materials and expands the plethora of promising application of MOFs@COFs hybrid porous materials in energy storage applications.     

Effect of Agave americana L. on the human,and Aspergillus oryzae S2 α-amylase inhibitions

Among phenolic compounds, Agave americana L. extract contained puerarin (38.4%) and p-coumaric acid (12.29%) (pCa). From the Lineweaver–Burk plots, pCa and puerarin demonstrated a competitive and a non competitive inhibitions towards human α-amylase activity, respectively. PCa exhibited a higher human inhibitory activity with an IC₅₀ of 98.8 μM which was about 2.3 times than acarbose. Puerarin (IC₅₀ = 3.87 μM) and pCa (IC₅₀ = 10.16 μM) also showed an excellent inhibition for Aspergillus oryzae S2 α-amylase activity. The inhibitions of the described biocatalysts compounds towards both amylases were significantly decreased when they were pre-incubated with starch. The binding modes of these compounds were evaluated in silico. The binding efficiency order of these molecules in terms of polar contact numbers for both enzymes was in agreement with the in vitro studies. These findings provided a rational reason to establish the isolated compounds capability as therapeutic target for hyperglycaemia modulation and antifungal therapy.     

Solvothermal Synthesis of Antimony Trioxide Sb2O3 Used as a Photocatalyst for Crystal Violet Dye Degradation

Moscow University Chemistry Bulletin - In the present research, antimony trioxide Sb2O3 particles have been successfully elaborated via solvothermal method and their photocatalytic ability for...