N-doped reduced graphene oxide anchored with δTa2O5 for energy and environmental remediation: Efficient light-driven hydrogen evolution and simultaneous degradation of textile dyes

Precipitation assisted facile hydrothermal method has been developed for anchoring nitrogen-doped reduced graphene oxide (NRGO) with tantalum pentoxide (TO) denoted as TO@NRGO. Synthesized materials were characterized using spectroscopic, optical and microscopic techniques and confirm transforming TO from orthorhombic to hexagonal phase (δ) upon anchoring with NRGO. TO@NRGO, TO and NRGO have been evaluated for photocatalytic hydrogen evolution, degradation of Methylene blue (MB) and Rhodamine B (RhB). The enhanced photocatalytic activity was observed in TO@NRGO nanocomposite compared to TO and NRGO due to decreased bandgap (2.5 eV) and increased surface area (312 m² g^?1). TO@NRGO evolved 19,500 µmol g^?1 of hydrogen for 3 h. TO@NRGO showed better degradation efficiency of 94 and 88% at a time of 100 min for MB and RhB, respectively. The parameters involved in photocatalytic dye degradation, like the effect of pH, catalyst dosage, and initial concentration of dyes, have been carefully optimized to achieve maximum performance of the catalyst. The stability and reusability of TO@NRGO are good and managed to degrade dyes effectively even after the 5th run. Thus, TO@NRGO could serve as a choice of material in resolving the issues related to energy and the environment.     

Potential Inhibitory Effect of Vitamins Against COVID-19

Coronavirus disease 2019 (COVID-19) is a current pandemic that has affected more than 195 countries worldwide. In this severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, when treatment strategies are not yet clear and vaccines are not available, vitamins are an excellent choice to protect against this viral infection. The rationale behind this study was to examine the inhibitory effect of vitamins B, C, and D against the main protease of SARSCoV-2 and angiotensin-converting enzyme 2 (ACE2), which have critical rolesin the immune system. Molecular docking, performed by using MOE-Dock of the Chemical Computing Group, was used to understand the mechanism. The vitamins all docked within the active sites of the M^pro (PDB ID:6LU7) and ACE2 receptor proteins (PDB ID:6VW1). Vitamins B and C delivered maximum energy scores against both targets, while vitamin D displayed a binding energy score of −7.9532 kcal/mol for M^pro and −7.9297 for ACE2. The efficiency of all three vitamins is higher than the binding energy score of chloroquine (−6.889 kcal/mol), which is now under clinical trials. The use of vitamins is beneficial, being immune system restorative, and they also act as anti-COVID agents. Although the potential beneficial effects of vitamin B and C are revealed through docking studies, further clinical trials are required for the validation of these results.     

Profiling the Effect of Targeting Wild Isocitrate Dehydrogenase 1 (IDH1) on the Cellular Metabolome of Leukemic Cells

Leukemia is one of the most common primary malignancies of the hematologic system in both children and adults and remains a largely incurable or relapsing disease. The elucidation of disease subtypes based on mutational profiling has not improved clinical outcomes. IDH1/2 are critical enzymes of the TCA cycle that produces α-ketoglutarate (αKG). However, their mutated version is well reported in various cancer types, including leukemia, which produces D-2 hydroxyglutarate (D-2HG), an oncometabolite. Recently, some studies have shown that wild-type IDH1 is highly expressed in non-small cell lung carcinoma (NSCLC), primary glioblastomas (GBM), and several hematological malignancies and is correlated with disease progression. This work shows that the treatment of wild-type IDH1 leukemia cells with a specific IDH1 inhibitor shifted leukemic cells toward glycolysis from the oxidative phosphorylation (OXPHOS) phenotype. We also noticed a reduction in αKG in treated cells, possibly suggesting the inhibition of IDH1 enzymatic activity. Furthermore, we found that IDH1 inhibition reduced the metabolites related to one-carbon metabolism, which is essential for maintaining global methylation in leukemic cells. Finally, we observed that metabolic alteration in IDH1 inhibitor-treated leukemic cells promoted reactive oxygen species (ROS) formation and the loss of mitochondrial membrane potential, leading to apoptosis in leukemic cells. We showed that targeting wild-type IDH1 leukemic cells promotes metabolic alterations that can be exploited for combination therapies for a better outcome.     

Mechanism of the corrosion inhibition of Zn Anode in NaOH by gelatine and some inorganic anions

The quantity of electricity required for passivation of Zn anode in NaOH solutions has been determined in absence and presence of different concentrations of gelatine, phthalic acid, sodium sulphide, sodium silicate or potassium chromate. The results obtained for gelatine in dilute alkali conform with a simple Langmuir model, whereas deviations are observed for the rest of the additives. The concentrations needed to establish a certain inhibiting efficiency increase wth increase in alkali concentration. The results are interpreted in the light of dissolution-precipitation mechanism.     

The effect of changes in the microstructure of steel on the inhibitive properties of some anodic and cathodic inhibitors

The electrode behaviour of spectroscopically pure Fe, steel samples containing 0·15–1·3%C and grey cast Fe in aerated 0·1M solutions of NaNO₂, Na benzoate and ZnSO₄, in 0·01M quinoline and in saturated CaCO₃ has been studied. The anodic (and cathodic) behaviour of these samples under potentiostatic or galvanostatic conditions has been followed in de-aerated NaNO₂ and ZnSO₄ solutions. It has been shown that anodic inhibitors are more sensitive to changes in the C-content of the samples than cathodic inhibitors, ZnSO₄ being almost indifferent to these changes.The protective nature of the cubic oxide formed in NaNO₂ or Na benzoate solutions is less efficient in presence of separate phases of ferrite, carbide or graphite than in its absence. Quinoline is more preferentially adsorbed on these separate phases. The effectiveness (in situ) of precipitated Ca(OH)₂ in blocking cathodic sites is counteracted by the presence of separate phases.     

Performance tradeoffs of optical WDM switches using different shared limited-range wavelength conversion mechanisms

The effects of different wavelength conversion ranging configurations on the performance of Wavelength Division Multiplexing (WDM) optical switches are investigated. Any-to-Any, Any-to-Range, Range-to-Any, and Range-to-Range conversion ranging configurations are considered. These mechanisms provide important design alternatives for optical switches due to technological limitations in the implementation of full range wavelength conversion in an all-optical wavelength converter device. Limited-range wavelength converter (LRWC) is a more economical and practical solution for WDM based optical networks. Differences among the input and output side ranging mechanisms and their effects on conversion resource sharing, and consequently on performance, are investigated. Any- to-Range ranging configuration is the most efficient mechanism and it operates comparably to Any-to-Any, reducing the need for complex control algorithms. The results help determine the most efficient ranging configuration for all-optical crossconnect.     

Restoration Probability Modelling for Active Restoration-Based Optical Networks with Correlation Among Backup Routes

Active restoration (AR) is a novel lightpath restoration scheme proposed recently to guarantee a certain degree of survivability in wavelength-division multiplexing (WDM) optical networks with a reasonable trade-off between capacity requirement and restoration time. In this paper, we conduct a comprehensive performance analysis for AR-based optical networks. In particular, we propose a novel analytical framework for modeling the restoration probability of a connection (the probability that the connection can be successfully restored in case of a failure) when the possible correlation among its multiple backup routes is incorporated. Although theoretically, we need to consider all the possible correlations between as many as Q) pairs of backup routes to analyze the restoration probability in a network with N nodes, and this high computation complexity may obscure the practicality of an approach, considering all the possible correlations among backup routes, our analysis in this paper indicates that by considering at most the possible correlations among any three successive backup routes of a connection, we can achieve a very good approximation to the simulated restoration probability of the connection, as verified by extensive simulation results upon two typical network topologies under various workloads. We find that the proposed framework can deeply investigate into the inherent relationship among restoration probability, wavelength channel utilization ratio, number of wavelengths per fiber, routes hop length, and wavelength conversion capability. As a result, the framework significantly contributes to the related areas by providing network designers with a quantitative tool to evaluate the restoration probability and, thus, the survivability of AR-based optical networks.