A phenoxy-bridged trinuclear Ni(ii) complex: synthesis, structural elucidation and molecular docking with viral proteins

A novel phenoxy-bridged trinuclear nickel(ii) complex [Ni3(mu-L)2(bipy)3](1) (where H3L= (E)-2-hydroxy-N-(2-hydroxy-3,5-diiodophenyl)-3,5-diiodobenzohydrazonic acid, bipy = 2,2'-bipyridyl) has been designed and synthesized as a potential antivirus drug candidate. The trinuclear Ni(ii) complex [Ni3(mu-L)2(bipy)3](1) was fully characterized via single crystal X-ray crystallography. The unique structure of the trinuclear nickel(ii) complex crystallized in a trigonal crystal system with P3221 space group and revealed distorted octahedral coordination geometry around each Ni(ii) ion. The X-ray diffraction analysis established the existence of a new kind of trinuclear metal system containing nickel(ii)-nickel(ii) interactions with an overall octahedral-like geometry about the nickel(ii) atoms. The non-bonded Ni-Ni distance seems to be 3.067 and 4.455 A from the nearest nickel atoms. The detailed structural analysis and non-covalent supramolecular interactions are also investigated by single crystal structure analysis and computational approaches. Hirshfeld surfaces (HSs) and 2D fingerprint plots (FPs) have been explored in the crystal structure to investigate the intermolecular interactions. The preliminary analysis of redox and magnetic characterization was conducted using cyclic voltammetry measurements and a vibrating sample magnetometer (VSM), respectively. This unique structure shows good inhibition performance for SARS-CoV-2, Omicron and HIV viruses. For insight into the potential application of the Ni(ii) coordination complex as an effective antivirus drug, we have examined the molecular docking of the trinuclear Ni(ii) complex [Ni3(mu-L)2(bipy)3](1) with the receptor binding domain (RBD) from SARS-CoV-2 (PDB ID: 7MZF), Omicron BA.3 variant spike (PDB ID: 7XIZ), and HIV protease (PDB ID: 7WCQ) viruses. This structure shows good inhibition performance for SARS-CoV-2, Omicron S protein and HIV protease viruses;the binding energies (DELTAG) and the respective Ki/Kd (inhibition/dissociation constants) correlation values are -8.9 (2.373 muM or 2373 nM), -8.1 (1.218 muM or 1218 nM) and -7.9 (0.874 muM or 874 nM), respectively. The results could be used for rational drug design against SARS-CoV-2 Omicron variant and HIV protease viruses.Copyright © 2023 The Royal Society of Chemistry.

Efficient Purification of Polyhistidine-Tagged Recombinant Proteins Using Functionalized Corundum Particles.

Immobilized metal affinity chromatography (IMAC) is a popular and valuable method for the affinity purification of polyhistidine-tagged recombinant proteins. However, it often shows practical limitations, which might require cumbersome optimizations, additional polishing, and enrichment steps. Here, we present functionalized corundum particles for the efficient, economical, and fast purification of recombinant proteins in a column-free format. The corundum surface is first derivatized with the amino silane APTES, then EDTA dianhydride, and subsequently loaded with nickel ions. The Kaiser test, well known in solid-phase peptide synthesis, was used to monitor amino silanization and the reaction with EDTA dianhydride. In addition, ICP-MS was performed to quantify the metal-binding capacity. His-tagged protein A/G (PAG), mixed with bovine serum albumin (BSA), was used as a test system. The PAG binding capacity was around 3 mg protein per gram of corundum or 2.4 mg per 1 mL of corundum suspension. Cytoplasm obtained from different E. coli strains was examined as examples of a complex matrix. The imidazole concentration was varied in the loading and washing buffers. As expected, higher imidazole concentrations during loading are usually beneficial when higher purities are desired. Even when higher sample volumes, such as one liter, were used, recombinant protein down to a concentration of 1 µg/mL could be isolated selectively. Comparing the corundum material with standard Ni-NTA agarose beads indicated higher purities of proteins isolated using corundum. His6-MBP-mSA2, a fusion protein consisting of monomeric streptavidin and maltose-binding protein in the cytoplasm of E. coli, was purified successfully. To show that this method is also suitable for mammalian cell culture supernatants, purification of the SARS-CoV-2-S-RBD-His8 expressed in human Expi293F cells was performed. The material cost of the nickel-loaded corundum material (without regeneration) is estimated to be less than 30 cents for 1 g of functionalized support or 10 cents per milligram of isolated protein. Another advantage of the novel system is the corundum particles' extremely high physical and chemical stability. The new material should be applicable in small laboratories and large-scale industrial applications. In summary, we could show that this new material is an efficient, robust, and cost-effective purification platform for the purification of His-tagged proteins, even in challenging, complex matrices and large sample volumes of low product concentration.

Determining the Effect of KmtR Mutants, E101Q, H102Q, and H111Q on the Metal Binding Affinities

Mycobacterium tuberculosis is the second leading infectious killer after COVID-19. The bacteria utilizes several metal transport systems to help it survive in the host.With an increase in the number of multiresistant, extensively resistant and totally drug-resistant strains, the development of new therapeutic strategies that target other essential pathways in the bacteria is critical. The bacteria contain several metal transport systems which are necessary for its survival. Additionally, the bacteria has two metalloregulators that are associated with nickel and cobalt export, NmtR and KmtR. The focus of this research is on KmtR, which represses the expression of the genes, cdf (which encodes the export protein) and kmtR. The goal of our research is to identify the residues that are responsible for binding the cognate metals, nickel and cobalt, as well as the noncognate metal, zinc, to KmtR. Mutagenesis studies coupled with metal binding experiments will be used to determine how KmtR binds these metals. The E101Q, H102Q, and H111Q mutants, among others, have been made, expressed, and purified in our lab. Data obtained from Isothermal Titration Calorimetry determined that all three mutant proteins bind cobalt with nanomolar affinities and the H111Q mutant KmtR proteins binds cobalt an order of magnitude weaker than the other two mutant proteins. Research reported as supported fully by the RI Institutional Development Award (IDeA) Network for Biomedical Research Excellence (RI-INBRE) from the National Institute of General Medical Sciences of the National Institutes of Health under grant #P20GM103430.Copyright © 2023 The American Society for Biochemistry and Molecular Biology, Inc.

Dynamic connectedness in commodity futures markets during Covid-19 in India: New evidence from a TVP-VAR extended joint connectedness approach

This paper presents a unique time-varying parameter vector autoregression (TVP-VAR) based extended joint connectedness approach to quantify the connectedness and transmission mechanism of shocks of nine commodities futures returns (namely;Gold and Silver from the category of precious metals;Copper, Lead, Zinc, Nickel and Aluminium from the category of base or industry metals;Natural Gas and Brent Crude Oil from energy sector) obtained from Multi Commodity Exchange of India Limited (MCX) from January 1, 2018 to December 31, 2021. This paper employs Balcilar et al. (2021)'s TVP-VAR extended joint connectedness approach, which combines the TVP-VAR connectedness approach of Antonakakis et al. (2020) with the joint spillover approach of Lastrapes and Wiesen (2021), to investigate the dynamic connectedness among the select commodity futures of interest. Our findings show that system-wide dynamic connectedness varies over time and is driven by economic events. The pandemic shocks appear to have an impact on system-wide dynamic connectedness, which peaks during the COVID-19 pandemic. Crude oil and zinc are the primary net shock transmitters, whereas gold and silver are the primary net shock receivers. We also discovered that the role of aluminum in shock transmitters and shock receivers changed during the course of the investigation. Pairwise connectivity, on the other hand, shows that Zinc, Copper, Nickel, and Crude oil are the key drivers of gold price changes, explaining the network's high degree of interconnectivity. During the study period, it was also discovered that silver has a significant influence on gold. Furthermore, in comparison to natural gas, gold's spillover activity is still relatively modest (on a scale), indicating that gold is less sensitive to market innovations. © 2023 Elsevier Ltd

DFT, ADMET, molecular docking and molecular dynamics studies of pyridoxal

We report in silico studies of pyridoxal, which is of interest both as a precursor for further functionalization due to the presence of the aldehyde functionality, as well as a bioactive compound. So far, the crystal structure of pyridoxal has not been reported and, thus, we have optimized its structure both under water solvation and in gas phase using the DFT calculations. Under water solvation conditions the optimized structure of pyridoxal is 7.62 kcal/mol more favorable in comparison to that in gas phase. The DFT calculations were also applied to verify optical and electronic properties of the optimized structure of pyridoxal in water. The HOMO and LUMO were revealed to subtract a set of descriptors of the so-called global chemical reactivity as well as to probe pyridoxal as a potential corrosion inhibitor for some important metals used in implants. The title compound exhibits the best electron charge transfer from the molecule to the surface of Ni and Co. Some biological properties of pyridoxal were evaluated using the respective on-line tools. Molecular docking was additionally applied to study interaction of pyridoxal with some SARS-CoV-2 proteins as well as one of the monkeypox proteins. It was established that the title compound is active against all the applied proteins with the most efficient interaction with nonstructural protein 15 (endoribonuclease) and Omicron Spike protein of SARS-CoV-2. Pyridoxal was found to be also active against the studied monkeypox protein. Interaction of pyridoxal with nonstructural protein 15 (endoribonuclease) was further studied using molecular dynamics simulation.Copyright © 2023 Indian Chemical Society

The Paradox of Green Growth: Challenges and Opportunities in Decarbonizing the Lithium-Ion Supply Chain

Global decarbonization is a megatrend destined to impact multiple sectors of the economy. The commodity sector in particular looks set to benefit, given the acute need for raw materials to feed the energy transition. This global transition will take decades and while an "all of the above” energy policy will be necessary, the lithium-ion battery promises to play a central role in the decarbonization of the transportation and grid scale energy storage sectors. With lithium-ion battery costs falling steadily since the early 1990s, many believe that the technology promises to become even more ubiquitous, helping to electrify the global economy. Recent exogenous shocks such as the US-China trade war, COVID-19, and the Russian invasion of Ukraine have underlined the fragility of global energy supply chains and the need for a resilient global energy infrastructure. While solutions to the exogenous shocks seem straightforward, there is an increasingly evident paradox. To achieve significant decarbonization and electrification goals, more, not fewer, battery raw materials will be required and the energy used to produce these materials will almost certainly originate from fossil fuels, possibly slowing the decline of the carbon intensity of industry. Innovation along the supply chain is the only realistic way to achieve large-scale decarbonization. This will require R&D, necessitating a coordinated response between the public and private sector as supply chains evolve. This chapter looks at the geopolitical, economic, technological, and legislative challenges and opportunities that green growth presents in the lithium-ion battery ecosystem as the industry embarks on a rapid growth phase. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

Evaluation of expression and titration of recombinant nucleocapsid protein as an immunogenic candidate against SARS-CoV2.

Introduction: Covid-19 epidemic results from an infection caused by SARS-CoV2. Evolution-based analyses on the nucleotide sequences show that SARS-CoV2 is a member of the genus Beta-coronaviruses and its genome consists of a single-stranded RNA, encoding 16 proteins. Among the structural proteins, the nucleocapsid is the most abundant protein in virus structure, highly immunogenic, with sequence conservatory. Due to a large number of mutations in the spike protein, the aim of this study was to investigate bioinformatics, expression of nucleocapsid protein and evaluate its immunogenicity as an immunogenic candidate Material(s) and Method(s): B and T cell epitopes of nucleocapsid protein were examined in the IEDB database. The PET28a-N plasmid was transferred to E. coli BL21(DE3) expression host, and IPTG induced recombinant protein expression. The protein was purified using Ni-NTA column affinity chromatography, and the Western blotting method was utilized to confirm it. Finally, mice were immunized with three routes of purified protein. Statistical analysis of the control group injection and test results was carried out by t-test from SPSS software. Result(s): The optimized gene had a Codon adaptation index (CAI) of 0/97 Percentage of codons having high-frequency distribution was improved to 85%. Expression of recombinant protein in E.coli led to the production of BoNT/B-HCC with a molecular weight of 45 kDa. The total yield of purified protein was 43 mg/L. Immunization of mice induced serum antibody response. Statistical analysis showed that the antibody titer ratio was significantly different compared to the control sample and the antibody titer was acceptable up to a dilution of 1.256000 Conclusion(s): According to the present study results, the protein can be used as an immunogenic candidate for developing vaccines against SARS-CoV2 in future research.Copyright © 2022, Semnan University of Medical Sciences. All rights reserved.

Evaluation of expression and titration of recombinant nucleocapsid protein as an immunogenic candidate against SARS-CoV2.

Introduction: Covid-19 epidemic results from an infection caused by SARS-CoV2. Evolution-based analyses on the nucleotide sequences show that SARS-CoV2 is a member of the genus Beta-coronaviruses and its genome consists of a single-stranded RNA, encoding 16 proteins. Among the structural proteins, the nucleocapsid is the most abundant protein in virus structure, highly immunogenic, with sequence conservatory. Due to a large number of mutations in the spike protein, the aim of this study was to investigate bioinformatics, expression of nucleocapsid protein and evaluate its immunogenicity as an immunogenic candidate Material(s) and Method(s): B and T cell epitopes of nucleocapsid protein were examined in the IEDB database. The PET28a-N plasmid was transferred to E. coli BL21(DE3) expression host, and IPTG induced recombinant protein expression. The protein was purified using Ni-NTA column affinity chromatography, and the Western blotting method was utilized to confirm it. Finally, mice were immunized with three routes of purified protein. Statistical analysis of the control group injection and test results was carried out by t-test from SPSS software. Result(s): The optimized gene had a Codon adaptation index (CAI) of 0/97 Percentage of codons having high-frequency distribution was improved to 85%. Expression of recombinant protein in E.coli led to the production of BoNT/B-HCC with a molecular weight of 45 kDa. The total yield of purified protein was 43 mg/L. Immunization of mice induced serum antibody response. Statistical analysis showed that the antibody titer ratio was significantly different compared to the control sample and the antibody titer was acceptable up to a dilution of 1.256000 Conclusion(s): According to the present study results, the protein can be used as an immunogenic candidate for developing vaccines against SARS-CoV2 in future research.Copyright © 2022, Semnan University of Medical Sciences. All rights reserved.

Nickel-Ion Activating Discarded COVID-19 Medical Surgical Masks for Forming Carbon-Nickel Composite Nanowires and Using as a High-Performance Lithium Battery Anode

With the prevalence of COVID-19, wearing medical surgical masks has become a requisite measure to protect against the invasion of the virus. Therefore, a huge amount of discarded medical surgical masks will be produced, which will become a potential hazard to pollute the environment and endanger the health of organisms without our awareness. Herein, a green and cost-effective way for the reasonable disposal of waste masks becomes necessary. In this work, we realized the transformation from waste medical surgical masks into high-quality carbon-nickel composite nanowires, which not only benefit the protection of the environment and ecosystem but also contribute to the realization of economic value. The obtained composite carbon-based materials demonstrate 70 S m-1conductivity, 5.2 nm average pore diameters, 234 m2g-1surface areas, and proper graphitization degree. As an anode material for lithium-ion batteries, the prepared carbon composite materials demonstrate a specific capacity of 420 mA h g-1after 800 cycles at a current density of 0.2 A g-1. It also displays good rate performance and decent cycling stability. Therefore, this study provides an approach to converting the discarded medical surgical masks into high-quality carbon nanowire anode materials to turn waste into treasure. © 2023 American Chemical Society. All rights reserved.

CO2-mediated thermal treatment of disposable plastic food containers

In accordance with global economic prosperity, the frequencies of food delivery and takeout orders have been increasing. The pandemic life, specifically arising from COVID-19, rapidly expanded the food delivery service. Thus, the massive generation of disposable plastic food containers has become significant environmental problems. Establishing a sustainable disposal platform for plastic packaging waste (PPW) of food delivery containers has intrigued particular interest. To comprise this grand challenge, a reliable thermal disposable platform has been suggested in this study. From the pyrolysis process, a heterogeneous plastic mixture of PPW was converted into syngas and value-added hydrocarbons (HCs). PPW collected from five different restaurants consisted of polypropylene (36.9 wt%), polyethylene (10.5 wt%), polyethylene terephthalate (18.1 wt%), polystyrene (13.5 wt%), polyvinyl chloride (4.2 wt%), and other composites (16.8 wt%). Due to these compositional complexities, pyrolysis of PPW led to formations of a variety of benzene derivatives and aliphatic HCs. Adapting multi-stage pyrolysis, the different chemicals were converted into industrial chemicals (benzene, toluene, styrene, etc.). To selectively convert HCs into syngas (H2 and CO), catalytic pyrolysis was adapted using supported Ni catalyst (5 wt% Ni/SiO2). Over Ni catalyst, H2 was produced as a main product due to C[sbnd]H bond scission of HCs. When CO2 was used as a co-reactant, HCs were further transformed to H2 and CO through the chemical reactions of CO2 with gas phase HCs. CO2-assisted catalytic pyrolysis also retarded catalyst deactivation inhibiting coke deposition on Ni catalyst. © 2022 Elsevier B.V.

Structural and theoretical investigations, Hirshfeld surface analysis and anti-SARS CoV-2 of nickel (II) coordination complex.

A nickel(II) Schiff base complex, [Ni(L)(DMF)](1), was synthesized by treating NiCl2.6H2O with an ONS-donor Schiff base ligand(H2L) derived from the condensation 3,5-Dichlorosalicylaldehyde and 4,4-Dimethyl-3-thiosemicarbazide in DMF. The geometry around the center metal ion in [Ni(L)(DMF)](1) was square planar as revealed by the data collection from diffraction studies. DFT calculations were performed on the complex to get a structure-property relationship. Hirshfeld surface analysis was also carried out in the crystal structure of nickel (II) Schiff base complex. Additionally, inspiring from recent developments to find a potential inhibitor for SARS-CoV-2 virus, we have also performed molecular docking study of [Ni(L)(DMF)](1) to see if our novel complex show affinity for main protease (Mpro) of SARS-CoV-2 Mpro (PDB ID: 6LZE). Interestingly, the results are found quite encouraging where the binding affinity and inhibition constant was found to be -6.6 kcal/mol and 2.358 µM, respectively, for the best docked confirmation of complex [Ni(L)(DMF)](1) with Mpro protein. This binding affinity is reasonably well as compared to recently known antiviral drugs. For instance, the binding affinity of complex [Ni(L)(DMF)](1) is found to be better than that of recently docking results of anti-SARS-CoV-2 drugs like chloroquine (-6.293 kcal/mol), hydroxychloroquine (-5.573 kcal/mol) and remdesivir (-6.352 kcal/mol) when targeted to the active-site of SARS-CoV-2 Mpro. Besides this, molecular docking against G25K GTP-nucleotide binding protein (PDB ID: 1A4R) was also studied. We believe that current results can intrigue not only for the biomedical community but also for the materials chemists who are engaged to explore the application coordination complexes.Communicated by Ramaswamy H. Sarma.

Screening and identification of potential MERS-CoV papain-like protease (PLpro) inhibitors; Steady-state kinetic and Molecular dynamic studies.

MERS-CoV belongs to the coronavirus group. Recent years have seen a rash of coronavirus epidemics. In June 2012, MERS-CoV was discovered in the Kingdom of Saudi Arabia, with 2,591 MERSA cases confirmed by lab tests by the end of August 2022 and 894 deaths at a case-fatality ratio (CFR) of 34.5% documented worldwide. Saudi Arabia reported the majority of these cases, with 2,184 cases and 813 deaths (CFR: 37.2%), necessitating a thorough understanding of the molecular machinery of MERS-CoV. To develop antiviral medicines, illustrative investigation of the protein in coronavirus subunits are required to increase our understanding of the subject. In this study, recombinant expression and purification of MERS-CoV (PLpro), a primary goal for the development of 22 new inhibitors, were completed using a high throughput screening methodology that employed fragment-based libraries in conjunction with structure-based virtual screening. Compounds 2, 7, and 20, showed significant biological activity. Moreover, a docking analysis revealed that the three compounds had favorable binding mood and binding free energy. Molecular dynamic simulation demonstrated the stability of compound 2 (2-((Benzimidazol-2-yl) thio)-1-arylethan-1-ones) the strongest inhibitory activity against the PLpro enzyme. In addition, disubstitutions at the meta and para locations are the only substitutions that may boost the inhibitory action against PLpro. Compound 2 was chosen as a MERS-CoV PLpro inhibitor after passing absorption, distribution, metabolism, and excretion studies; however, further investigations are required.

Preparation of LiFePO4/C cathode material by extracting Fe2O3 from laterite nickel ore by ammonium jarosite method

In the context of the COVID-19 pandemic and the war between Russia and Ukraine, domestic oil prices have skyrocketed. Saving resources and develop lithium ion batteries with excellent performance are particularly important. In view of unreasonable utilization of non-target elements in laterite nickel ore and high energy consumption of traditional sulfate roasting laterite nickel ore, a pioneering idea was adopted to combine laterite nickel ore with LiFePO 4 , which not only meets the resource saving but also prepares lithium ion batteries with excellent performance, in this study. Using ammonium sulfate roasting laterite nickel ore-ammonium jarosite iron precipitation and hydrolysis preparation of Fe 2 O 3 -carbon thermal reduction preparation of LiFePO 4 /C process means, to achieve the ultimate goal of preparing LiFePO 4 from laterite nickel ore. Determining the optimum conditions of each part of experiment by single factor experiment and orthogonal experiment. It was concluded that under the optimal preparation conditions, the discharge specific capacity of lithium ion battery was 164.56 mAh/g at the rate of 0.5 C, and it was 94% of the theoretical capacity. After 100 cycles, we could find that the discharge specific capacity could be maintained at 162.78 mAh/g, and the capacity retention rate still reached 98%. • Preparation of LiFePO 4 /C cathode material from laterite nickel ore for rational utilization of resources. • Ammonium sulfate roasting laterite nickel ore can greatly improve the recovery rate of nickel and iron resources • The ammonium jarosite method has high iron precipitation rate, simple operation and less pollution. • The preparation of LiFePO 4 /C cathode material by carbothermal reduction method is conducive to practical applications. [ FROM AUTHOR]

New nickel(ii) Schiff base complexes as potential tools against SARS-CoV-2 Omicron target proteins: an in silico approach

Herein, we report the in silico design and synthesis of two new nickel(ii) coordination complexes, viz., [Ni(L-1)][(PPh3)]DMF (1) and [Ni(L-2)] (2), based on Schiff bases derived from the 2-hydroxy-1-naphthaldehyde moiety (where, (LH2)-H-1 = (E)-3-(((5-chloro-2-hydroxyphenyl)imino)methyl)naphthalene-2-ol), ((LH2)-H-2 = 2,2 & PRIME;-((1E,1 & PRIME;E)-(ethane-1,2-diylbis(azaneylylidene))bis(methaneylylidene))bis(naphthalen-2-ol)), PPh3 = (triphenylphosphine). The synthesized ligands (LH2)-H-1 and (LH2)-H-2 were coordinated to Ni(ii) ions through the tridentate-ONO and tetradentate-N2O2 donor atoms, respectively. The newly synthesized complexes were fully characterized using X-ray crystallography analysis. The synthesized complexes (1) and (2) crystallized in the triclinic and monoclinic crystal system with the P1 and P21/c space group, respectively, and exhibited a square planar geometry around the Ni(ii) ions. Computational approaches were employed to determine the structure-property relationship of the complexes. Hirshfeld surface analysis was also performed to investigate intermolecular interactions in the crystal systems. The strength of the interaction and 3D topology of crystal packing were visualized through an energy framework. To gain insights into the potential application of Ni(ii) complexes as effective SARS-CoV-2 Omicron inhibitors, we performed the following docks (a) Ni(ii) complexes with S protein from original SARS-CoV-2 (PDB ID: 7CWO), (b) Ni(ii) complexes with selected Omicron targets (PDB ID: 7QTK and 7WK8) and (c) controls ivermectin and levosalbutamol with the original SARS-CoV-2 spike protein and the Omicron S proteins. The synthesized Ni(ii) complexes (1) and (2) showed good docking results with the S protein of SARS-CoV-2, where the binding energies (& UDelta;G) and respective K-i (inhibition constants) correlation values are -7.38 (3.87 mu M) and -8.82 (341.77 nM), respectively. The molecular docking results revealed that the synthesized complexes (1) and (2) with the SARS-CoV-2 Omicron target protein (PDB ID: 7QTK) resulted the binding energy (& UDelta;G) of -7.46 kcal mol(-1) with an inhibition constant (K-i) of 3.39 mu M and binding energy (& UDelta;G) of -7.56 kcal mol(-1) with an inhibition constant (K-i) of 2.89 mu M, respectively. Similarly, the synthesized Ni(ii) complexes (1) and (2) with the SARS-CoV-2 Omicron target protein (PDB ID: 7WK8) exhibited the binding energy (& UDelta;G) and inhibition constant (K-i) of -7.03 kcal mol(-1) and 7.08 mu M and -7.89 kcal mol(-1) and 1.64 mu M, respectively. It was predicted that ivermectin shows a larger binding energy (& UDelta;G) for S proteins compared to levosalbutamol after molecular docking. Further, in silico ADMET to predict the drug-likeness behaviour and pharmacokinetic response of the synthesized complexes was also explored. Overall, the present study suggests that nickel(ii) complexes can be considered as potential therapeutic drugs against the Omicron target protein of SARS-CoV-2.

Impact Of Covid-19 On The Linkages Between Indochina Metal Futures Markets

This paper attempts to test whether the Covid-19 pandemic has an impact on the linkages of the metal futures market of India and China. Taking Daily closing prices from 4 Jun 2016 to 23 Apr 2021 for the seven metals, including copper, aluminum, zinc, lead, nickel, gold, and silver, have been included in the study in the pre-announcement and post-announcement of covid-19 as a pandemic. The autoregressive distributed lag (ARDL) bound test and Johansen cointegration test report no cointegrating relationship between the markets for all the metal futures before the covid period. There is no change in the absence of cointegration in the post-announcement period of Covid-19. Similarly, Granger causality results report no change in the short-run relationship between the metal futures markets except for silver futures. The results have implications for portfolio managers and investors looking to reshuffle their portfolios in the light of changes in the market due to the covid-19 pandemic. Copyright © 2022 Wolters Kluwer Medknow Publications. All rights reserved.

Preparation of LiFePO4/C cathode material by extracting Fe2O3 from laterite nickel ore by ammonium jarosite method

In the context of the COVID-19 pandemic and the war between Russia and Ukraine, domestic oil prices have skyrocketed. Saving resources and develop lithium ion batteries with excellent performance are particularly important. In view of unreasonable utilization of non-target elements in laterite nickel ore and high energy consumption of traditional sulfate roasting laterite nickel ore, a pioneering idea was adopted to combine laterite nickel ore with LiFePO4, which not only meets the resource saving but also prepares lithium ion batteries with excellent performance, in this study. Using ammonium sulfate roasting laterite nickel ore-ammonium jarosite iron precipitation and hydrolysis preparation of Fe2O3-carbon thermal reduction preparation of LiFePO4/C process means, to achieve the ultimate goal of preparing LiFePO4 from laterite nickel ore. Determining the optimum conditions of each part of experiment by single factor experiment and orthogonal experiment. It was concluded that under the optimal preparation conditions, the discharge specific capacity of lithium ion battery was 164.56 mAh/g at the rate of 0.5 C, and it was 94% of the theoretical capacity. After 100 cycles, we could find that the discharge specific capacity could be maintained at 162.78 mAh/g, and the capacity retention rate still reached 98%.

Synergistic induction of IL-6 production in human bronchial epithelial cells in vitro by nickel nanoparticles and lipopolysaccharide is mediated by STAT3 and C/EBPß.

We previously reported that delivery of nickel nanoparticles (NiNPs) and bacterial lipopolysaccharide (LPS) into the lungs of mice synergistically increased IL-6 production and inflammation, and male mice were more susceptible than female mice. The primary goal of this study was to utilize an in vitro human lung epithelial cell model (BEAS-2B) to investigate the intracellular signaling mechanisms that mediate IL-6 production by LPS and NiNPs. We also investigated the effect of sex hormones on NiNP and LPS-induced IL-6 production in vitro. LPS and NiNPs synergistically induced IL-6 mRNA and protein in BEAS-2B cells. TPCA-1, a dual inhibitor of IKK-2 and STAT3, blocked the synergistic increase in IL-6 caused by LPS and NiNPs, abolished STAT3 activation, and reduced C/EBPß. Conversely, SC144, an inhibitor of the gp130 component of the IL-6 receptor, enhanced IL-6 production induced by LPS and NiNPs. Treatment of BEAS-2B cells with sex hormones (17ß-estradiol, progesterone, or testosterone) or the anti-oxidant NAC, had no effect on IL-6 induction by LPS and NiNPs. These data suggest that LPS and NiNPs induce IL-6 via STAT3 and C/EBPß in BEAS-2B cells. While BEAS-2B cells are a suitable model to study mechanisms of IL-6 production, they do not appear to be suitable for studying the effect of sex hormones.

Association between COVID-19 and Heavy Metal Pollution in Iraqi Cities Determined from Hierarchical Prediction

This study assesses the relationship between coro-navirus (COVID-19) and the spread of various heavy metal contaminants across Iraq. The study collects all confirmed, recovered, and death cases of the COVID-19 virus at its onset in Iraq until May 2, 2020, comparing Iraq with the top three infected countries in the world (the United States Spain, and Italy). In addition, numerous heavy metal contamination in different Iraqi cities have been summarized and associated with the allowable upper and lower worldwide standard limits. Furthermore, the study introduces a hierarchical predictive approach for the relationship between confirmed infected cases and deaths due to the COVID-19 virus and heavy metal contamination in various Iraqi cities. It is concluded that all the studied Iraqi cities have heavy metal contamination for different chemical elements exceeding the allowable standard limits. Extreme contents of copper, nickel, lead, and zinc are concentrated in Al-Qadisiyah, Al-Sulaimaniyah, Erbil, and Baghdad with limits of 160 µg/g, 240.9 µg/g, 378 µg/g, and 1,080 µg/g, respectively. Based on the hierarchical prediction approach, a linear positive relationship between both confirmed cases and deaths due to COVID-19 with different heavy metal contamination was obtained with a maximum coefficient of determination (R2) of 0.97.

Synthesis and characterization of violurate-based Mn(II) and Cu(II) complexes nano-crystallites as DNA-binders and therapeutics agents against SARS-CoV-2 virus

Synthesis and structural characterization of nano crystallites of bis-violurate-based manganese(II) and copper(II) chelates is the subject of the present study. Analytical data and mass spectra as well as thermal analysis determined the molecular formulas of the present metal chelates. Spectroscopic and magnetic measurements assigned the structural formula of the present violurate metal complexes. The spectroscopic and magnetic investigations along with structural analysis results indicated the square planar geometry of both the Mn(II) and Cu(II) complexes. The structural analysis of the synthesized metal complexes was achieved by processing the PXRD data using specialized software Expo 2014. Spectrophotometeric and viscosity measurements showed that violuric acid and its Mn(II) and Cu(II) complexes successfully bind to DNA with intrinsic binding constants Kb from 38.2 x 105 to 26.4 x 106 M-1. The antiviral activity study displayed that the inhibitory concentrations (IC50) of SARS-CoV-2 by violuric acid and its Mn(II) and Cu(II) complexes are 84.01, 39.58 and 44.86 lM respectively. Molecular docking calculations were performed on the SARS-CoV-2 virus protein and the computed binding energy values are -0.8, -3.860 -5.187 and -4.790, kcal/mol for the native ligand, violuric acid and its Mn(II) and Cu(II) complexes respectively. Insights into the relationship between structures of the current compounds and their degree of reactivity are discussed.(c) 2022 The Author(s). Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Bio-monitoring of atmospheric heavy metal pollution of major emergency events using moss bags:a case study in Xichang

In order to trace and monitor the atmospheric heavy metal pollution in Xichang City, an investigation activity was carried out with a sort of moss (Taxiphyllum taxirameum) (packed in moss bags) as a biological indicator for monitoring heavy metal pollution. The investigation was conducted from the period from April 2019 to April 2020, during which two grave emergency events occurred during spring monitoring period from January 15 to April 15, 2020, i.e., COVID-19 and "3.30"severe forest fire in Xichang, which inevitably affected the atmospheric quality. Based on the concentration analysis of 12 kinds of heavy metal, including Al, Cr, Fe, Cu, Ni, Pb, Mn, Hg, Zn, V, As and Ba contained in the moss and the local meteorological data, comparing those informative data before and after the time when the emergency events toke place, the paper made an analysis on the impacts of two enormous emergency events on the air pollution of heavy metal in Xichang. The results showed that total amount of enrichment of above-mentioned 12 heavy metals in spring (January 15 to April 15, 2020) is (12.85 +or- 1.57) mg/g, which was significantly higher than in the other three seasons (p < 0.01), but no significant discrepancies about the total enrichment amount in the other three seasons (p > 0.05). Primarily because of COVID-19 pandemic, the level of motor vehicles emissions cut down, and the decrease of the tourism in the related areas perhaps causing the decline of pollution of Pb. In addition, the decrease of unbalanced emission of pollutants led to a noted increase of atmospheric oxidation in urban area, thus boosting the formation of secondary particulate matter, and the particulate matter from surrounding industrial sources was transported into the urban area;as a result, remarkable increases of Hg concentration of moss within the moss bags were detected downwind the industrial area located in the urban fringe. Consequently, the investigation showed that the moss-bag method is an effective biological tool for monitoring air heavy metal pollution, which could reflect the impacts of major pollution events on air quality.