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Lead ions are an efficient neurotoxic metal that results in serious disorders for human beings, including poisoning, kidney and liver disorders, hepatitis, anaemia, encephalopathy, and nephritic syndrome. The low-cost and eco-friendly biocomposite from Zea mays sponge (ZMS) biomass encapsulated using Na-alginate in the cross-linked matrix (ZMS/Na-alginate) as a biosorbent. A statistical approach uses full factorial design space to optimize the best conditions for preparation beads. The effect of concentrations (w/v, g/100 mL) of Na-alginate (X1), ZMS biomass (X2), and CaCl2 cross-linker (X3) retesting for Pb(II) ions elimination from the aquatic medium in batch mode. The supreme values optimized for X1, X2, and X3 are relevant to 4.5%, 2.5%, and 1.97%. After optimization using response surface methodology, the maximum lead removal by ZMS/Na-alginate biocomposite was 97.11%. The ZMS/Na-alginate biocomposite was characterized using scanning electron microscopy and attenuated total reflection spectroscopy to investigate physical and chemical modification in the structure during the biosorption system. Therefore, the synthesized ZMS/Na-alginate beads show considerable stability during 5 consecutive adsorption–desorption cycles. This approach study demonstrates that the optimized condition affects the removal of lead ions. The findings support using the modified raw biomass as a potential absorbent for heavy metal ions removal from aqueous media. [ABSTRACT FROM AUTHOR]

Purpose: To determine the patterns of progression after 68Ga prostate-specific membrane antigen (PSMA)-ligand positron emission tomography (PET)/computed tomography (CT)-guided radiation therapy (RT) for recurrent oligometastatic prostate cancer (PCa).Methods and Materials: One hundred and eight patients with increased prostate-specific antigen levels, who received 68Ga-PSMA-ligand PET/CT-guided RT for recurrent oligometastatic disease after primary therapy for PCa were included. The biochemical progression-free survival and distant disease-free survival after PSMA-ligand PET/CT-guided RT were determined. The patterns of progression were determined using renewed 68Ga-PSMA-ligand PET/CT in patients with biochemical progression and compared with the clinical target volume of the 68Ga-PSMA-ligand PET/CT-guided RT. The frequency of infield and outfield relapses was recorded.Results: A total of 97.2% (105 of 108) of patients showed a decrease in prostate-specific antigen levels after RT and were classified as biochemical responders. After the median follow-up of 18 months, 43.5% (47 of 108) of the patients experienced biochemical progression, resulting in an estimated biochemical progression-free survival of 16 months. Renewed 68Ga-PSMA-ligand PET/CT allowed localization of recurrent disease in 91.7% (33 of 36) of patients. Analysis of the patterns of progression resulted in a cumulative infield relapse rate of 12.1% (4 of 33) and a cumulative outfield relapse rate of 87.9% (29 of 33). The resultant median disease-free survival was 11 months. In terms of the pattern of progression, we observed a shift in the pattern of metastases toward skeletal involvement and distant lymph node metastases. Of these patients, 45.5% (15 of 33) were treated with further RT to delay initiation or escalation of systemic therapies.Conclusion: PSMA-ligand PET/CT-guided RT for relapsed PCa with limited tumor burden allowed individualization of treatment approaches, provided effective local control, and resulted in considerably prolonged biochemical progression-free survival. As indicated by the PSMA-ligand PET/CT-based patterns of progression, repeated PET/CT-guided RT may represent a treatment option in well-selected patients with relapse after RT for oligometastatic disease. [ABSTRACT FROM AUTHOR]

Real-contaminated soils are a significant source of combined polycyclic aromatic hydrocarbons and potentially toxic elements, which call for special methods of immobilization. Herein, for the first time, Fe-based metal-organic frameworks (MIL-101(Fe)) were composited with biochar to use as an amendment to a real highly contaminated soil in dynamic column leaching experiments. In this regard, MIL-101(Fe) was successfully mounted on the surface of rice husk biochar (RBC) to create a composite (RBC-MIL). Response surface methodology was used to model Cu contents in the leachate by considering two independent parameters: sorbent to soil mass ratio and leaching time. The effectiveness of Cu immobilization was observed to be improved in the presence of 3% RBC-MIL and a leaching period of two days with a minimum concentration of 0.2 mg L−1. According to the Tessier's chemical fractionation findings, RBC-MIL remarkably eliminated the acid soluble fraction of Cu by deploying it in the residual fraction. The composite was more effective at polycyclic aromatic hydrocarbon retention by having a capacity of 15.70 μg g−1, as opposed to RBC, which had a capacity of 4.86 μg g−1. Overall, our results demonstrate that MIL-based biochar composite can be utilized as advanced amendments for remediating real contaminated soil. [Display omitted] • MIL-101 was used for the first time in an actual polluted soil to immobilize Cu. • Novel use of the RSM was introduced to simulate leaching in dynamic soil columns. • Biochar-MIL-101(Fe) composite significantly immobilized Cu and PAHs. • The composite induced immobilization of 2–3 rings of PAH and acid soluble Cu. [ABSTRACT FROM AUTHOR]

Abstract: Metallothioneins are the proteins containing seven Cd atoms in tetrahedral arrangement of S atoms. For this compound full multiple scattering XAFS calculations have been used as a tool for verification of structural models generated using molecular dynamic. To determine the sensitivity of the spectrum to different structural parameters and to check does the best-fit XANES spectrum correspond to the correct structure of the complex we have tested method for Cd(SPh)4 model compound. [Copyright &y& Elsevier]

The article presents a comprehensive investigation of the crystal structure, impedance spectra, magnetic, magnetodielectric, and magnetoresistive properties of (1- x)CoFe 2 O 4 – x PbTiO 3 composites with varying concentrations (х = 0, 0.2, 0.4, and 0.6). The study also examines the effects of applying a uniaxial pressure of 1 GPa to the synthesized powders using Bridgman anvils. Our findings reveal that the synthesis of these composites results in the formation of an additional phase, lead hexaferrite PbFe 12 O 19 , which exhibits multiferroic properties. Additionally, the coherent scattering region of the components is significantly reduced after mechanical activation. Notably, the real part of the resistivity ρ ′(ω) of nanostructured CoFe 2 O 4 ceramics increases eightfold at T = 240 °C. The composites demonstrate significant magnetoresistance at room temperature, reaching up to 250 %. The study also reveals that the signs of the magnetodielectric MD (B) and magnetoresistive coefficient MR (B) vary with the frequency of the measuring field for certain concentrations. Using the first-order reversal curve (FORC) method, it was observed that after nanostructuring CoFe 2 O 4 through mechanical activation, the interaction field H u shifts from ± 0.6 kOe to ± 0.8 kOe, while the coercive field H c increases from 1.05 kOe to 5 kOe. Moreover, the two-dimensional FORC maps of the composites show increased complexity, due to the formation of additional magnetic phases. [ABSTRACT FROM AUTHOR]

Abstract: Ni-isocyanide and Ni-acac complexes have been studied by X-ray absorption spectroscopy. Theoretical analysis has been done using self-consistent full multiple scattering (MS) approach within both muffin-tin (MT) model of the potential and non-MT finite deference method. For the isocyanide complex, it was shown that MS theoretical spectra reproduce all structural details of the X-ray absorption near-edge structure (XANES), but also that it is important to consider the non-MT effects in the potential for a correct simulation of the shape of the pre-edge structures. The contribution of a non-constant potential in the interstitial regions is extremely important for the interpretation of the XANES of Ni(acac)2. [Copyright &y& Elsevier]

Abstract: The local and electronic structure of nitrogen-related defects in thin film of InN (0001) has been studied using synchrotron-based X-ray absorption near edge structure (XANES) spectroscopy. Several defect levels within the band gap and the conduction band of InN were clearly resolved in XANES spectra around the nitrogen K-edge. Theoretical analysis of XANES data includes advanced “ab initio” simulations: self-consistent full multiple scattering calculations using muffin-tin approximation, non-muffin-tin finite difference approach to study the influence of non-muffin-tin effects on XANES shape as well as advanced local density approximation scheme for optimization of initial geometry around nitrogen defects. Theoretical analysis of XANES data allows to attribute the level observed at 1.7eV above the conduction band mimimum to antisite nitrogen and a sharp resonance at 3.2eV above the conduction band minimum to molecular nitrogen. [Copyright &y& Elsevier]

Abstract: Three alternative approaches have been applied to calculate As K-edge XANES of InAs: multiple scattering (MS) theory, non-muffin-tin finite difference method (FDM) and full potential linearized augmented plane wave (FLAPW) method. Such combination allows to make the distinction between two types of non-muffin-tin effects. First, in the interstitial region the potential is not constant. Second, the covalent bonds increase the charge density between nearest atoms and lead to additional loss of spherical symmetry of the potential within MT spheres. [Copyright &y& Elsevier]

Abstract: X-ray absorption near edge structure (XANES) spectra at the cooper L2,3-edge of small cooper nanoclusters has been studied. Theoretical interpretation of XANES spectra measured for small copper nanoclusters have been performed. Theoretical analysis is based on a self-consistent full multiple scattering theory of X-ray absorption as well as on non-muffin-tin finite difference method (FDM). This approach allows choosing the best model for local geometry of small cooper nanoclusters. [Copyright &y& Elsevier]

Towards solving the poor electrochemical performance of LiCoPO 4 as a cathode in Lithium-ion batteries, here we propose a novel durable one-pot technique. Mil-88a metal-organic framework (MOF) nanoparticles have been incorporated through LiCoPO 4 synthesis to form a metal-carbon layer after calcination. The structure of our novel cathode has been investigated using XRD, XRF, and TEM. The TEM images showed that the increase in the concentration of Mil-88a to 3% and annealed under air led to forming of a homogeneously distributed shell layer from porous carbon and doped with iron oxide nanoparticles (10–40 nm). The X-ray photoelectron spectra of LiCoPO4@Mil-88a verifies the presence of a Fe-rich surface layer on the nanoparticle surface of LiCoPO 4. The electrochemical studies assured that the 1st cycle yielded a discharge-specific capacity of 138 mAhg−1. The Mil-88a MOF is a basis for metal atoms and carbon, increasing the bulk conductivity. [ABSTRACT FROM AUTHOR]

We present here the quantum model of a Ni solid-state electron spin qubit on a silicon surface with the use of a density-functional scheme for the calculation of the exchange integrals in the non-collinear spin configurations in the generalized spin Hamiltonian (GSH) with the anisotropic exchange coupling parameters linking the nickel ions with a silicon substrate. In this model the interaction of a spin qubit with substrate is considered in GSH at the calculation of exchange integrals J ij of the nanosystem Ni 7 –Si in the one-electron approach taking into account chemical bonds of all Si-atoms of a substrate (environment) with atoms of the Ni 7 -cluster. The energy pattern was found from the effective GSH Hamiltonian acting in the restricted spin space of the Ni ions by the application of the irreducible tensor operators (ITO) technique. In this paper we offer the model of the quantum solid-state N-spin qubit based on the studying of the spin structure and the spin-dynamics simulations of the 3d-metal Ni clusters on the silicon surface. The solution of the problem of the entanglement between spin states in the N-spin systems is becoming more interesting when considering clusters or molecules with a spectral gap in their density of states. For quantifying the distribution of the entanglement between the individual spin eigenvalues (modes) in the spin structure of the N-spin system we use the density of entanglement (DOE). In this study we have developed and used the advanced high-precision numerical techniques to accurately assess the details of the decoherence process governing the dynamics of the N-spin qubits interacting with a silicon surface. We have studied the Rabi oscillations to evaluate the N-spin qubits system as a function of the time and the magnetic field. We have observed the stabilized Rabi oscillations and have stabilized the quantum dynamical qubit state and Rabi driving after a fixed time (0.327 μs). The comparison of the energy pattern with the anisotropic exchange models conventionally used for the analysis of this system and, with the results of the experimental XANES spectra, shows that our complex investigations provide a good description of the pattern of the spin levels and the spin structures of the nanomagnetic Ni 7 qubit. The results are discussed in the view of the general problem of the solid-state spin qubits and the spin structure of the Ni cluster. [ABSTRACT FROM AUTHOR]