A Multistage In Silico Study of Natural Potential Inhibitors Targeting SARS-CoV-2 Main Protease

Among a group of 310 natural antiviral natural metabolites, our team identified three compounds as the most potent natural inhibitors against the SARS-CoV-2 main protease (PDB ID: 5R84), M^pro. The identified compounds are sattazolin and caprolactin A and B. A validated multistage in silico study was conducted using several techniques. First, the molecular structures of the selected metabolites were compared with that of GWS, the co-crystallized ligand of M^pro, in a structural similarity study. The aim of this study was to determine the thirty most similar metabolites (10%) that may bind to the M^pro similar to GWS. Then, molecular docking against M^pro and pharmacophore studies led to the choice of five metabolites that exhibited good binding modes against the M^pro and good fit values against the generated pharmacophore model. Among them, three metabolites were chosen according to ADMET studies. The most promising M^pro inhibitor was determined by toxicity and DFT studies to be caprolactin A (292). Finally, molecular dynamics (MD) simulation studies were performed for caprolactin A to confirm the obtained results and understand the thermodynamic characteristics of the binding. It is hoped that the accomplished results could represent a positive step in the battle against COVID-19 through further in vitro and in vivo studies on the selected compounds.     

A New Algorithm for Measuring and Optimizing the Manipulability Index

The estimation of the performance characteristics of robot manipulators is crucial in robot application and design. Furthermore, studying the manipulability index for every point within the workspace of any serial manipulator is considered an important problem. Such studies are required for designing trajectories to avoid singular configurations. In this paper, a new method for measuring the manipulability index is proposed, and then some simulations are performed on different industrial manipulators such as the Puma 560 manipulator, a six DOF manipulator and the Mitsubishi Movemaster manipulator.     

Preparation and evaluation of a new anti-corrosive coating based on asphalt cement blended with polyesteramide resin for steel protection

Asphalt cement is a material commonly used in coating applications due to its good adhesion properties and relatively low cost. Unfortunately it has the drawback of being slow to dry. Long polyesteramide resin (PEA) is predominantly used for air-dry and force-dry industrial coatings onto metal surfaces, yet is considered to be a relatively weak material. This paper focuses on the potential synergy of mixing asphalt cement, of penetration grade 60/70, with polyesteramide resin to produce industrial coatings for steel applications, with the aim of overcoming the slow drying time of the asphalt cement and the relative weakness of PEA resin. To achieve this aim, PEA resin was mixed with asphalt cement in a range of concentrations from 3 to 12% (w/w). The prepared coating blends were characterised physically using scanning electron microscopy (SEM), while the performance of the coatings were evaluated for mechanical properties and corrosion resistance in selective chemical reagents, following complete immersion for the duration of 84 days. The results obtained concluded that generally, a blend of asphalt cement and polyesteramide resin produces an effective material for industrial coating applications. Also, 9% and 12% PEA resin content produced high-quality anti-corrosive material as compared to virgin asphalt cement. The degree of modification depends upon the properties of the asphalt and the content level of the polyesteramide.     

The impact of seismic interpretation on the hydrocarbon trapping at Falak field,Meleiha, Western Desert,Egypt

The object from this study is to find ways to develop field and discover the possible reservoirs and appropriate solutions to avoid the problems we have faced before in the drilled wells that led to drilling dry wells close to producing wells. A set of twenty reflection sections have been used to highlight the subsurface structural setting and the hydrocarbons entrapment styles in Falak field in the northern Western Desert, this is achieved through an integrated geological and geophysical studies utilizing a number of maps and cross sections, all of that for demonstrating all the chances for exploring or developing the field. The reflectors are Ras-Qattara formation, Khatatba-2D member, Masajid formation, Alam El Beuib 3G member, AEB 3F member, AEB 3E member, AEB 3D member, AEB 2A member, AEB 1 member, Alamein Dolomite formation, Dahab Shale member, Kharita formation, Bahariya 5 member, Bahariya 4 member, Bahariya 1 member, Abu Roash “G” member, Abu Roash “E” member, Abu Roash “A” member, and the Apollonia formation. The N-S and E-W trending seismic sections revealed normal faults forming shape seems to be horsts all over the mapped field, these faults led to thin Cretaceous section in the up thrown block area compared to thick section on the downthrown block of the two main faults, for some instances dry hole conditions occur due to missing of structural closure on both the up thrown block and the downthrown. The TWT maps on the top of the traced reflectors reveal different structural closures with set of normal faults constructing three way dip closure in most of these faults and big shape like horst.     

Effect of high energy ball milling on strengthening of Cu-ZrO2 nanocomposites

In this paper, copper matrix nanocomposites reinforced by 5 and 10?wt% ZrO₂ particles were produced by mechanical milling technique at different milling times. The produced nanocomposite powders were investigated by X-ray diffraction technique and transmission electron microscopy. The effect of high energy ball milling on the morphology, microstructure and microhardness of the produced composites has been investigated. After that cold compaction was applied to the prepared powders under a pressure of 700?MPa and sintered at 950?°C for 2?h in hydrogen atmosphere. The results showed that increasing milling time improves microhardness of the prepared nanocomposites. The microhardness of Cu-10%ZrO₂ after 20?h milling is 3.76 times larger than pure Cu. This improvement is attributed firstly to the presence of ZrO₂ nanoparticles in addition to the improvement coming from the grain refinement and crystallite size reduction occurred due to mechanical alloying. So, in spite of the crystallite size of Cu-10%ZrO₂ nanocomposite is reduced to 10.75?nm compared to 105.5?nm for pure Cu, the presence of ZrO₂ nanoparticles plays a major role on mechanical properties improvement.     

Optimizing the Performance of the Meso-Scale Continuous-Flow Photoreactor for Efficient Photocatalytic CO2 Reduction with Water Over Pt/TiO2/RGO Composites

Catalysis Letters - Tuning the reaction parameters to maximize products yield is one of the major needs for any process. The goal of this research is to increase the reduction of CO2 with water by...     

Evaluation of synthesized polyaniline nanofibres as corrosion protection film coating on copper substrate by electrophoretic deposition

Journal of Materials Science - In this current paper, we report the use of inexpensive, simple electrophoretic deposition (EPD) technique in developing polyaniline (PANI) aqueous colloidal...