Malaria, a persistent and ancient adversary, continues to impact vast regions worldwide, afflicting millions and severely affecting human health and well-being. Recently, despite significant progress in combating this parasitic disease, malaria remains a major global health concern, especially in areas with limited resources and vulnerable populations. Consequently, identifying and developing effective agents to combat malaria and its associated dysfunctions is essential therefore the two new Schiff base ligands incorporated Co(II), Ni(II), Cu(II) and Zn(II) ions were synthesized and thoroughly characterized. The synthesized compounds were assessed for in vitro anti-malarial and antimicrobial efficacy, compounds (9, 10) demonstrated highest potential with IC50=1.08±0.09 to 1.18±0.04 μM against P. falciparum and MIC=0.0058 μmol/mL against C. albicans and E. coli, respectively. The complexes (5, 6) were effectively reduce mitigate oxidative stress with lowest IC50 value of 2.69±0.12 to 2.87±0.09 μM. Moreover, the biological findings were reinforced by a molecular docking investigation involving the potential compounds (2, 7-10) against dihydroorotate dehydrogenase and sterol 14-alpha demethylase proteins which exposed complex\'s excellent biological response than their parent ligands. ADMET profiling was used to confirm the compounds\' oral drug-like features. This research offers promising prospects for future multi-functional drug innovations targeting malaria, pathogenic infections, and oxidative stress.

In sodium-cooled fast reactors, the wettability of sodium with materials is closely related to sodium-related operations and the detection accuracy of instruments and meters, so how to achieve the selection of materials with different wettability requirements is a key problem in engineering design. To meet these requirements, the wetting behaviors of liquid sodium with nine transition metals were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), and molecular dynamics (MD) simulations. The results show that metals such as zinc and gold, which react with sodium to form intermetallic compounds at the interface, exhibit superior wettability. Followed by the metals that have strong interatomic interactions even though they do not react with sodium or dissolve each other, such as cobalt, nickel and copper, while the wettability of these systems tends to be poor at low temperatures. Systems that do not react with each other or have strong interatomic affinities proved to be the most difficult to wet. Notably, metals with the closest-packed crystal structures of fcc and hcp generally have better wettability than those with a bcc structure. They can be a valuable guide for experimental research and technical control.

BACKGROUND: The efficient catalysis of CO2 adsorption and activation presents a formidable challenge due to its pronounced thermodynamic stability and kinetic inertia. Previous experiments have left gaps in understanding the promotional effects and underlying mechanism of potassium. In this study, we systematically investigate CO2 adsorption and activation on clean and potassium-preadsorbed low index surfaces of transition metals. Theoretical results reveal a substantial augmentation in CO2 binding strength when potassium is introduced, concomitant with a general reduction in activation energies. Notably, linear correlations are significant on close-packed metal surfaces without and with potassium additive. Through a comprehensive analysis encompassing geometric parameters, electronic structures, and energy decomposition, we discern the physical underpinnings of the potassium effect. This enhancement is primarily ascribed to direct electron transfer and dipole-dipole interactions. Furthermore, we scrutinize the impact of an external electric field, demonstrating that the application of a negative electric field accelerates CO2 activation, mirroring the effects observed with potassium.
METHODS: All the periodic density function theory (DFT) calculations were performed by the Vienna Ab Initio Simulation package (VASP). The interaction between nucleus and valence electron was described using the pseudopotentials found in the projector augmented wave method (PAW). Throughout the entire work, the Bayesian error estimation functional (BEEF) was used.

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Transition-metal dichalcogenides (TMDs) have promising properties for their use as catalysts of CO2 reduction to methane via the Sabatier reaction. In this article we use density-functional theory calculations to gain insight into the energetics of this reaction for Mo/W-based and S/Se-based TMDs with non-, Ni- and Cu-doping. We show that sulfur-based TMDs with Ni/Cu doping exhibit better indicators for catalytic performance of the CO2 reduction reaction than non-doped and doped TMDs without active sites. In addition, the role of the transition metal was found to a much smaller influence in the reaction than the role of the chalcogen and dopant atoms, which influence the bonding strength and type, respectively.

Crystals of l-asparagine monohydrate doped with Fe(III) were studied by Raman spectroscopy in a diamond anvil cell (DAC) in the spectral range from 100 to 3200 cm-1 and pressures up to 9.2 GPa. The behavior of external modes suggests conformational changes between 3.0 and 4.0 GPa mainly affecting the CH2 group. X-ray diffraction measurements with synchrotron radiation were performed in the angular range from 3 to 12 degrees (2θ) up to 9.3 GPa. The lattice parameters contract up to 9.3 GPa, with the exception of parameter b, which exhibits expansion from 7.2 GPa. The lattice parameters exhibit discontinuities between 3.0 and 4.0 GPa, this effect is compatible with conformational changes. Such modifications occur without a change in symmetry, at least up to 9.3 GPa. Under decompression, down to atmospheric pressure, the original Raman spectrum is recovered, showing that the conformational change and the other changes are all reversible.

In this work, the molecular mechanism of Lactobacillus paracasei bio-colloid clumping under divalent metal ions treatment such as zinc, copper and magnesium at constant concentrations was studied. The work involved experimental (electrophoretic - capillary electrophoresis in pseudo-isotachophoresis mode, spectroscopic and spectrometric - FT-IR and MALDI-TOF-MS, microscopic - fluorescent microscopy, and flow cytometry) and theoretical (DFT calculations of model complex systems) characterization. Electrophoretic results have pointed out the formation of aggregates under the Zn2+ and Cu2+ modification, whereas the use of the Mg2+ allowed focusing the zone of L. paracasei biocolloid. According to the FT-IR analysis, the major functional groups involved in the aggregation are deprotonated carboxyl and amide groups derived from the bacterial surface structure. Nature of the divalent metal ions was shown to be one of the key factors influencing the bacterial aggregation process. Proteomic analysis showed that surface modification had a considerable impact on bacteria molecular profiles and protein expression, mainly linked to the activation of carbohydrate and nucleotides metabolism as well with the transcription regulation and membrane transport. Density-functional theory (DFT) calculations of modeled Cu2+, Mg2+ and Zn2+ coordination complexes support the interaction between the divalent metal ions and bacterial proteins. Consequently, the possible mechanism of the aggregation phenomenon was proposed. Therefore, this comprehensive study could be further applied in evaluation of biocolloid aggregation under different types of metal ions.

Transition metals are widespread in aquatic environments and can be harmful when concentrations exceed thresholds. Especially for fish, an important component of the human diet, low concentrations of transition metals will directly affect their well-being. Different taxa are protected by unified water quality criteria (WQC) thresholds, which rarely consider the ecological status and economic value of different species. There is therefore an urgent need to study taxon-specific sensitivity. The present study established the species sensitivity distributions of nine typical transition metals (Cr, Mn, Fe, Ni, Cu, Zn, Ag, Cd and Hg) for protecting freshwater and seawater fish based on non-parametric kernel density estimation methods, and then derived their acute and chronic HC5-values. The results showed that Ag and Hg have the highest acute toxic potency to fish in freshwater as well as seawater. Compared with marine fish, freshwater fish were more tolerant to acute exposure to Cr, Fe, Ni and Zn, whilst being more sensitive to Ag and Cd. Moreover, edible fish are more sensitive than other fish to these metals in both freshwater and seawater, encouraging more protection of economically valuable fish that may potentially affect human health. The study provides a strong reference for future research on taxon-specific WQC for transition metals.

Herein, we report the synthesis of eight new mononuclear and binuclear Co2+, Ni2+, Cu2+, and Zn2+ methoxy thiosemicarbazone (MTSC) complexes aiming at obtaining thiosemicarbazone complex with potent biological activity. The structure of the MTSC ligand and its metal complexes was fully characterized by elemental analysis, spectroscopic techniques (NMR, FTIR, UV-Vis), molar conductivity, thermogravimetric analysis (TG), and thermal differential analysis (DrTGA). The spectral and analytical data revealed that the obtained thiosemicarbazone-metal complexes have octahedral geometry around the metal center, except for the Zn2+-thiosemicarbazone complexes, which showed a tetrahedral geometry. The antibacterial and antifungal activities of the MTSC ligand and its (Co2+, Ni2+, Cu2+, and Zn2+) metal complexes were also investigated. Interestingly, the antibacterial activity of MTSC- metal complexes against examined bacteria was higher than that of the MTSC alone, which indicates that metal complexation improved the antibacterial activity of the parent ligand. Among different metal complexes, the MTSC- mono- and binuclear Cu2+ complexes showed significant antibacterial activity against Bacillus subtilis and Proteus vulgaris, better than that of the standard gentamycin drug. The in silico molecular docking study has revealed that the MTSC ligand could be a potential inhibitor for the oxidoreductase protein.

Recently, the design of new biological metal-ligand complexes has gained a special interest all over the world. In this research, new series of mixed ligand complexes from meloxicam (H2mel) and glycine (Gly) were synthesized. Structures of the compounds were investigated employing elemental analyses, infrared, electronic absorption, 1H NMR, thermal analyses, effective magnetic moment and conductivity. The estimated molar conductivity of the compounds in 1 × 10-3 M DMF solution indicates the non-electrolyte existence of the examined complexes. Additionally, the effective magnetic moment values refer to the complexes found as octahedral molecular geometry. The data of the infrared spectra showed the chelation of H2mel and Gly with metal ions from amide oxygen and nitrogen of the thyizol groups of H2mel and through nitrogen of the amide group and oxygen of the carboxylic group for Gly. Thermal analyses indicated that the new complexes have good thermal stability and initially lose hydration water molecules followed by coordinated water molecules, Gly and H2mel. The kinetic parameters were calculated graphically using Coats-Redfern and Horowitz-Metzeger methods at n = 1 and n ≠ 1. The density functional theory (DFT) calculations were performed at B3LYP levels. The optimized geometry of the ligand and its complexes were obtained based on the optimized structures. The data indicated that the complexes are soft with η value in the range 0.114 to 0.086, while η = 0.140 for free H2mel. The new prepared complexes were investigated as antibacterial and antifungal agents against some phyto- and human pathogens and the minimum inhibitory concentration (MIC) data showed that complex (A) has the lowest MIC for Listeria and E. coli (10.8 µg/mL).