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This study investigates the magnetic response of Ho3+ doped Ni 0.4 Cu 0.6 Ho y Fe 2-y O 4 (y = 0.0, 0.02, 0.04, 0.06, and 0.08) spinel ferrites (SFs) and their correlation with crystallite size. The synthesis was achieved using a sol-gel auto-combustion (SGAC) route and performed different characterizations, including X-ray diffraction (XRD), Scanning electron microscope (SEM), Energy dispersive x-ray (EDX), Inductively coupled plasma atomic emission spectroscopy (ICP-AES), and vibrating sample magnetometer (VSM) analysis. The cubic spinel phase was verified via XRD in pure NCF and Ho3+ doped NCF samples. The lattice constant (a) was improved from 8.344 Å to 8.378 Å. The substitution of Ho3+ ions led to a decrease in porosity from 42.22 % to 39.54 %. The introduction of Ho3+ ions also reduced the crystallite size (D) from 37.05 nm to 27.72 nm. The specific surface area (S) was increased from 27.44 g/cm2 to 36.14 g/cm2 with the doping of Ho3+. The average particle size (D S) was decreased from 54 nm to 35 nm. The EDX and ICP-AES analyses confirmed the good agreement with the theoretical composition. The VSM measurements provided insights into their magnetic properties. Furthermore, the doping of Ho3+ ions enhanced coercivity (H C), while reducing saturation magnetization (M S) from 64.35 emu/g to 16.22 emu/g. The decrease in crystalline anisotropy (K) observed at higher concentrations of Ho3+ may result from the increase in coercivity, potentially attributable to the smaller crystallite size of the single-domain SFs particles. The single-phase matrix and their magnetic behaviour showed that the Ho3+ doped Ni–Cu SFs samples are suitable for high-frequency applications. [Display omitted] • Ni 0.4 Cu 0.6 Ho y Fe 2-y O 4 was prepared via the sol-gel auto-combustion technique. • The crystallite size was the minimum (27.72 nm) for the y = 0.08 (NCHF4) sample. • The sample has y = 0.08 (NCHF4) and contains maximum coercivity (1031.44 Oe). • The sample has y = 0.08 (NCHF4) and is best-suitable for high-frequency applications. [ABSTRACT FROM AUTHOR]

Synthesis of unique morphologies in photocatalytic materials, coupled with utilization of wide-spectrum solar energy through rare earth doping, holds significant promise to maximize the potential of photocatalysts. Herein in, cube-like Holmium (Ho) doped Bi 5 Nb 3 O 15 was synthesized by the hydrothermal method and integrated with reduced graphene oxide (rGO) sheets. As synthesized Ho–Bi 5 Nb 3 O 15 @rGO composite along its analogs i.e., Bi 5 Nb 3 O 15 and Ho–Bi 5 Nb 3 O 15 was characterized by XRD, SEM, FT-IR, TGA, I–V, EIS, Mott-Schottky and photo-current measurements. Phase studies showed that crystallite size for Bi 5 Nb 3 O 15 , Ho–Bi 5 Nb 3 O 15 , and Ho–Bi 5 Nb 3 O 15 @rGO was 27.4, 25.5, and 13.5 nm, respectively. Optical analysis exhibited a reduction in the band gap in consequent to Ho doping from 2.54 to 2.19 eV for Ho–Bi 5 Nb 3 O 15. Conductivity and photo-current measurements showed a remarkable increase in both electrical conductivity and photo-response of Ho–Bi 5 Nb 3 O 15 upon its incorporation into rGO matrix, reaching maximum values of 1.72 × 10−2 S/m and 0.66 μA, respectively. The enhanced photocatalytic activity of Ho–Bi 5 Nb 3 O 15 @rGO was ensured through the outstanding photo-degradation efficiency (96.5 %) against crystal violet (CV), greater than Bi 5 Nb 3 O 15 (49 %) and Ho–Bi 5 Nb 3 O 15 (63.4 %). Additionally, Ho–Bi 5 Nb 3 O 15 @rGO showed sufficient potential towards the degradation of acetylsalicylic acid (ASA) with 79.1 % photo-degradation. This elevated photocatalytic activity of Ho–Bi 5 Nb 3 O 15 @rGO is believed to be contributed by the collaborative outcomes aroused from the Ho-doping and heterojunction fabrication among cubical Ho–Bi 5 Nb 3 O 15 and rGO sheets. Hence, our work proposes an efficient strategy for the development of innovative photolytic materials for sustainable wastewater remediation. [ABSTRACT FROM AUTHOR]

In spite of available treatment options, glaucoma continues to be a leading cause of irreversible blindness in the world. Current glaucoma medications have multiple limitations including: lack of sustained action; requirement for multiple dosing per day, ocular irritation and limited options for drugs with different mechanisms of action. Previously, we demonstrated that pregabalin, a drug with high affinity and selectivity for CACNA2D1, lowered IOP in a dose-dependent manner. The current study was designed to evaluate pregabalin microemulsion eye drops and to estimate its efficacy in humans using in silico methods. Molecular docking studies of pregabalin against CACNA2D1 of mouse, rabbit, and human were performed. Pregabalin microemulsion eye drops were characterized using multiple in vivo studies and its stability was evaluated over one year at different storage conditions. Molecular docking analyses and QSPR of pregabalin confirmed its suitability as a new IOP-lowering medication that functions using a new mechanism of action by binding to CACNA2D1 in all species evaluated. Because of its prolonged corneal residence time and corneal penetration enhancement, a single topical application of pregabalin ME can provide an extended IOP reduction of more than day in different animal models. Repeated daily dosing for 2 months confirms the lack of any tachyphylactic effect, which is a common drawback among marketed IOP-lowering medications. In addition, pregabalin microemulsion demonstrated good physical stability for one year, and chemical stability for 3–6 months if stored below 25 °C. Collectively, these outcomes greatly support the use of pregabalin eye drops as once daily IOP-lowering therapy for glaucoma management. [Display omitted] • Molecular docking analyses estimate strong binding affinity of pregabalin, a novel therapy for open angle glaucoma • Pregabalin microemulsion eye drops supports once daily use by extending the precorneal drug residence time up to 24 h • Pregabalin microemulsion eye drops didn't have any tachyphylactic effect upon repeated dosing for 2 months • Pregabalin microemulsion eye drops is chemically stable for 3–6 month at temperature below 25 °C. [ABSTRACT FROM AUTHOR]

This work provides an environmental approach to utilise Blast furnace slag (BFS) waste for the processing of aluminium oxide (Al2O3-BFS) as an efficient adsorbent for uranium removal from wastewater. The composition of BFS is less variable and this makes it a low cost and abundant raw material for preparing a solid base Al2O3-BFS. The silica material was initially removed and then the aluminium content was separated by precipitation with sodium hydroxide depending on pH control (pH 5.5). The raw BFS and Al2O3-BFS were characterised via various methods, such as; XRD, Zeta potential, N2 adsorption-desorption isotherm, DLS, and FT-IR. BFS exhibited the typical type III isotherm with an H3-type hysteresis loop. The curve of Al2O3-BFS exhibited the typical IV isotherms with a H2-type hysteresis loop. The BET surface and average pore sizes of the Al2O3-BFS are 137.7 m2 g-1 and 3.9 nm, respectively. Experiments and discussions were performed in terms of balance, isothermal, kinetic, and applicability. The finding provides proof of the ability of synthesised Al2O3-BFS to remove U(VI) ions from wastewater as an efficient adsorbent with a maximum sorption capacity value of 62 mg/g. The pseudo second, Langmuir and Dubinin-Radushkevich models were found suitable to explain the rate kinetics and isotherm of uranium removal. Uranium sorption on Al2O3-BFS may occur via inner-sphere complex and ion-exchange between uranium ions and HO-Al2O3-BFS groups. The higher elution efficiency of Al2O3-BFS indicates a promising adsorbent in the technology of U(VI) removal. [ABSTRACT FROM AUTHOR]

Carboxy‐thioether‐thiolato Ti (IV) complex (TiCTT) and its graphene oxide nanocomposite (GO–TiCTT) were prepared and characterized for the development of novel compounds with enhanced antibacterial and anticancer capabilities, and the loading ratio of TiCTT was found to be approximately 33.3%. Thermal studies and zeta potential revealed that GO–TiCTT is more stable than GO, whereas SEM and TEM revealed efficient TiCTT adsorption on the surface of GO. Various biophysical procedures were used to investigate the interactions of CTT, TiCTT, GO, and GO–TiCTT nanocomposite with bovine serum albumin (BSA). The results revealed that the intrinsic fluorescence quenching of BSA resulting from low concentrations was caused by the formation of stable BSA adducts via the binding interaction with BSA. The stable adduct had a stoichiometry of 1:1 and binding constants (Kb) in the order of 105 M1 at 310 K for CTT, TiCTT, and GO–TiCTT, indicating a very strong binding interaction with BSA. Based on the sign and magnitude of the free energy change (G#), it can be concluded that the binding process with BSA was spontaneous, with van der Waals force and hydrogen bonding interaction as the main interaction forces. A combined quenching process was observed at higher concentrations of these compounds. Using the stopped‐flow technique, the TiCTT release behavior from the nanocomposite was investigated, and the GO–TiCTT system demonstrated pH‐responsive and sustained drug release. Furthermore, when compared to GO, CTT, TiCTT, and GO–TiCTT nanocomposite demonstrated good antibacterial activity against both Gram‐positive and Gram‐negative bacteria. They also have higher cytotoxicity against HepG2 human liver cancer cells than CTT. The calculated BSA‐binding constants matched the antimicrobial and cytotoxic results well. As a result, this research could lead to the development of a drug delivery system. [ABSTRACT FROM AUTHOR]

Reaction of bis(2-picolyl)amine (BPA) with Ni(II) salt yielded [(BPA)NiCl2(H2O)] (NiBPA). The Ni(II) in NiBPA bound to a BPA ligand, two chloride, and one aqua ligands. Because most medications inhibit biological processes by binding to a specific protein, the stopped-flow technique was used to investigate DNA/protein binding in-vitro, and a mechanism was proposed. NiBPA binds to DNA/protein more strongly than BPA via a static quenching mechanism. Using the stopped-flow technique, a mechanism was proposed. BSA interacts with BPA via a fast reversible step followed by a slow irreversible step, whereas NiBPA interacts via two reversible steps. DNA, on the other hand, binds to BPA and NiBPA via the same mechanism through two reversible steps. Although BSA interacts with NiBPA much faster, NiBPA has a much higher affinity for DNA (2077 M) than BSA (30.3 M). Compared to NiBPA, BPA was found to form a more stable BSA complex. When BPA and NiBPA bind to DNA, the Ni(II) center was found to influence the rate but not the mechanism, whereas, for BSA, the Ni(II) center was found to change both the mechanism and the rate. Additionally, NiBPA exhibited significant cytotoxicity and antibacterial activity, which is consistent with the binding constants but not the kinetic stability. This shows that in our situation, biological activity is significantly more influenced by binding constants than by kinetic stability. Due to its selectivity and cytotoxic activity, complex NiBPA is anticipated to be used in medicine. [ABSTRACT FROM AUTHOR]

The goal of the current study is to improve the characteristics and bioavailability of the drug picoplatin (PPt) by encapsulating it in chitosan nanoparticles (CS NPs) which allows for the targeted delivery of cytotoxic cargo to cancerous tissue, reducing toxic side effects and raising the therapeutic index. When picoplatin was delivered into the CS, it was able to produce a complex with CS (PPt@CS NPs) that had an appropriate particle size of 275 ± 10 nm, a reasonably low PDI of 0.15 ± 0.05, and high stability (ζ = −22.1 ± 0.3 mV). Since almost all pharmaceuticals work by binding to specific proteins or DNA, the in vitro binding mechanism and affinity of bovine serum albumin (BSA), low molecular building units of nucleic acids (5−GMP), and Glutathione (GSH) (considering that cisplatin resistance could be due to a reaction between cisplatin and GSH) to PPt and PPt@CS NPs were examined using stopped-flow and other spectroscopic approaches. Through two reversible processes, a rapid second-order binding followed by a slower first-order isomerization reaction, and a static quenching mechanism, PPt and PPt@CS NPs bind to BSA with relative reactivity of around (PPt)/(PPt@CS NPs) = 1/2.5. The 5−GMP interaction studies demonstrated that, in addition to changing the binding mechanism, PPt's encapsulation in CS increases its rate of reaction through coordination affinity. PPt interacted with 5-GMP via two reversible processes, a rapid second-order binding to phosphate followed by a slower first−order migration to the N7 of pyrimidine moiety. PPt@CS NPs showed weaker binding to GSH compared to PPt and hence PPt@CS NPs exhibits a lower resistance factor. It was also found that the in vitro drug release of PPt@CS NPs in PBS at pH 7.4 was steady, releasing 30 % of the PPt in just 5 h. Nonetheless, 75 % of the release in a pH 5.4 solution containing 10 mM GSH—a solution that mimics the tumor microenvironment—shows that the PPt@CS NPs system is sensitive to GSH and specifically targets malignant tissue. The encapsulation of PPt in CS complex maintained its anticancer activity, as shown by an in vitro cell-survival assay on HepG2 cancer cell lines and also cleavage efficiency toward the minor groove of pBR322 DNA via the hydrolytic way. These findings collectively suggested that inclusion PPt in CS would be an effective strategy to formulate a novel picoplatin formulation intended for use as targeted anticancer treatment. [Display omitted] • Drug targeting PPt@CS NPs was developed to deliver PPt drug to cancerous tissue. • BSA interaction's kinetic data showed a relative reactivity of (PPt@CS NPs)/(PPt) = 1/2.5. • In vitro binding mechanism and affinity of BSA, 5-GMP, and Glutathione were examined and mechanism was proposed. • In vitro PPt release in PPt@CS NPs showed a controlled release pattern that was GSH-responsive. • PPt@CS NPs still maintains antitumor activities against HepG2 cells and cleavage efficiency toward pBR322 DNA. [ABSTRACT FROM AUTHOR]

Visible-light-responsive photocatalysis has been recognized as a sustainable strategy to address environmental pollution, but semiconductor-based photocatalysts often suffer from many shortcomings, including low visible light absorption and rapid recombination of photo-generated charge carriers. In this regard, rationally designed composite materials have gained substantial prominence, as achieving an ideal photocatalyst's characteristics in a single component material is frequently difficult. In the present study, we have synthesized pure (WO 3) and indium-doped tungsten oxide (In-WO 3) by the facile solvothermal route. The doped material was anchored on a 2D rGO matrix to fabricate the In-WO 3 /rGO composite. The structural, morphological, electrical, and optical properties of the as-synthesized materials were investigated as a function of doping and composite fabrication by various physical and electrochemical techniques. The comparative photocatalytic performance was evaluated by degrading Congo Red (CR) dye and paracetamol (PCM) drug. The composite material shows degradation efficiencies of ∼96 % (K=0.0174 min−1) and ∼91 % (K=0.0144 min−1) for CR dye and PCM drug, respectively. The boosted catalytic performance corresponds to the declined band gap (2.53 eV) and increased conductivity (0.1270 Sm−1), which enhances its visible light absorption and a surge in the charge carrier's population. The kinetics, relative contribution of different active species generated, and the potential mechanism of photodegradation reaction are discussed in detail. The significant increase in photocatalytic performance of the fabricated In-WO 3 /rGO composite discloses its promising catalytic potential for the degradation of recalcitrant organic pollutants. [Display omitted] • In-WO 3 /rGO composite-based photocatalyst has been fabricated. • The fabricated catalyst shows efficient charge separation and migration. • The photocatalytic potential was investigated by degrading Congo Red and Paracetamol. • The degradation of targeted organic pollutants follows first-order kinetics. • The photocatalyst exhibits excellent stability without a decrease in catalytic performance. [ABSTRACT FROM AUTHOR]

Glassy samples from the undoped ternary system Na2O–ZnO–P2O5 in combination with other samples from the same system doped with variable amounts of MoO3 (0.25, 0.5, or 1 gm/batch) were successfully melted under ordinary, oxidizing, or reducing conditions followed by annealing. Fourier transform infrared spectrophotometric measurements in combination with optical absorption spectra were recorded before and after doping with variable concentrations of MoO3 in multiple melting media both as prepared or after being subjected to (8 Mrad) gamma irradiation dose. The studied spectral properties of the glasses were correlated with variations with the existing valence state of the Mo ions and the effects of gamma irradiation on the optical spectra and IR vibrational bands together with the role of the condition of melting the batches. The optical spectra of the glasses reveal pronounced UV and visible bands due to trace iron (Fe3+) ions as impurities or the sharing of the low valence states of the added molybdenum ions. The FTIR peaks show condensed spectra of phosphate groups (Q2, Q3), and the effects of dopant are limited because of low percent. Gamma irradiation causes distinct variations in the undoped spectra, but the MoO3-doped glasses show some shielding behavior. [ABSTRACT FROM AUTHOR]

Two zinc(II) complexes, DBZ and DBZH4, that have (ZnN3S2) cores and differ in the bridging mode of the ligating backbone, effectively bind to BSA. The binding affinity varies as DBZ > DBZH4 and depends on the ligand structure. At low concentrations, both complexes exhibit dynamic quenching, whereas at higher concentrations they exhibit mixed (static and dynamic) quenching. The energy transfer mechanism from the BSA singlet excited state to DBZ and DBZH4, is highly likely according to steady-state fluorescence and time-correlated singlet photon counting. Molecular docking was used to support the mode of interaction of the complexes with BSA and showed that DBZ had more energy for binding. Furthermore, antibacterial testing revealed that both complexes were active but to a lesser extent than chloramphenicol. In comparison to DBZH4, DBZ has higher antibacterial activity, which is consistent with the binding constants, molecular docking, and particle size of adducts. These findings may have an impact on biomedicine. [ABSTRACT FROM AUTHOR]

A new complex, [Ni(Tren)(Barb)(H2O)](Barb)(Barb-H)·2H2O (NiC) {Tren = tris(2-aminoethyl)amine and Barb = 5,5-diethlybarbiturate}, has been synthesized and characterized. The nickel(II) complex was grafted to g-C3N4, forming NiC@g-C3N4. The obtained NiC complex and its hybrid material NiC@g-C3N4 were characterized by FT-IR, TGA-DSC, UV–vis, SEM-EDX, and XRD. Single crystal X-ray crystallography shows that NiC exhibits NiN5O octahedral geometry. The results also show that the complex molecules are connected via N–H⋅⋅⋅⋅O hydrogen bonds. The complex NiC and NiC@g-C3N4 show oxidative stress effects on in vivo experiments. They also showed an increase in tissue damage markers that are represented by increase in tissue levels of malondialdehyde (MDA) in brain, liver, kidney and heart. Both materials showed inhibitory activity for examined antioxidants such as glutathione-S-transferase (GST), superoxide dismutase (SOD), glutathione (GSH) and glutathione reductase (GSH-R). The destructive effects were clearer for the NiC@g-C3N4 composite in liver, brain and kidney, respectively. The grafting of NiC complex in g-C3N4 is responsible for improving the catalytic activity of the compound, due to the synergistic effect of both components and facile recovery, as well recycling of the catalyst. The immobilization of the synthesized nickel(I) complex [Ni(Tren)(Barb)(H2O)](Barb)(Barb-H)•2H2O (NiC) to the graphitic carbon nitride (g-C3N4) as electron rich surface, forming the hybrid material NiC@g-C3N4, which provides both the benefits i.e improved catalytic activity owing to the synergistic effect of both components and facile recovery, recycling of the catalyst. [ABSTRACT FROM AUTHOR]

Summary: A new bipyridine‐containing manganese (II) complex, namely [(BPy)2MnCl2]·0.5H2O (MnC), was synthesized and characterized. Spectral and X‐ray structural features revealed that MnC has an octahedral environment around Mn(II). Graphene oxide (GO) was noncovalently functionalized with the MnC. MnC‐ and (MnC/GO)‐modified glassy carbon (GC) interfaces with different loading densities (0.2, 0.4, 0.8, and 1.0 mg cm−2) were tested as electrocatalysts for efficient generation of H2 in 0.1 M KOH solution. The GC‐MnC catalysts exhibited high electrocatalytic activity for the HER, which enhances upon increasing the catalyst's loading density. The GC‐MnC catalyst's HER activity, at any tested loading density, was found to further increase upon supporting MnC on GO. The best performing electrocatalyst, namely GC‐(MnC/GO) with a loading density of 1.0 mg cm−2, exhibited high HER catalytic activity with a low onset potential value of −22 mV vs. reference hydrogen electrode (RHE) and a high exchange current density of 0.75 mA cm−2. It delivered a current density of 10 mA cm−2 at an overpotential value of 119 mV. In addition, it recorded a Tafel slope value of −114 mV dec−1. These HER electrochemical kinetic parameters approached those measured here for the commercial Pt/C under the same operating conditions (−10 mV vs. RHE, 0.88 mA cm−2, 113 mV dec−1, and 110 mV to yield a current density of 10 mA cm−2) and also comparable to the most active molecular electrocatalysts for H2 generation from aqueous alkaline electrolytes published in the literature. The long‐term stability of the best performing electrocatalyst, namely GC‐MnC (1.0 mg cm−2)/GO, was evaluated using cyclic voltammetry (repetitive cycling up to 5000 cycles) and chronoamperometry (48 hours) techniques, and the obtained results revealed its promising stability. A plausible mechanism for the interaction of MnC with GO was proposed based on density functional theory (DFT) calculations. DFT calculations confirmed the catalytic role of the supporting material (GO) on the fabricated metal complex in catalyzing the HER. [ABSTRACT FROM AUTHOR]

The aim of this research is to evaluate three types (pulsed motion double head, hook type, and pneumatic comb) of commonly used hand-held olive harvesters for small scale olive orchards. The evaluation criteria were harvester productivity (Pr), fruit removal percentage (FR), fruit damage (FD), specific consumed energy (SCE), and olive harvesting cost (HC). Overall evaluation criterion (OEC) was developed depending upon the relative weight of each evaluation criterion. Relative weights were arranged according to the importance of each evaluation criterion. The results showed that the highest value of the overall evaluation criterion was 84.9% for the T3P1500 treatment (pulsed motion double head olive harvester at speed of 1500 rpm). Through this condition, the values of evaluating criteria were 88.4 kg h-1, 98%, 6.6%, 17.0 W h kg-1, and 0.041 $ kg-1 for Pr, FR, FD, SCE and HC respectively. In addition, the values of OEC of the pulsed motion double head olive harvester for the other treatments (T1P1100 and T2P1300) outperformed the other harvesters at all treatments. [ABSTRACT FROM AUTHOR]

In the present study, a modified solvothermal reaction of (hematite) with titanium(IV) butoxide and gold(III) chloride produced ternary Au@TiO2/α-Fe2O3 nanocomposite. The designed Au@TiO2/α-Fe2O3 photocatalyst exhibits nanoring-like structure with high crystallinity indicating the possibility of manufacturing extreme structures and offering a new nanostructure that was not previously studied. Both TiO2 and Au nanoparticles (NPs) were found to be dispersed uniformly on the α-Fe2O3 surface. X-ray diffraction powder technique combined with X-ray photoelectron (XPS) and Raman spectroscopy confirm the formation of the three materials with cubic Au, anatase TiO2 and hematite α-Fe2O3 structures, respectively. The photocatalytic activity proves the performance of this ternary heterojunction to decomposes different pollutants. It was found that, TiO2 absorbs UV-light, α-Fe2O3 absorbs both UV and Visible light and plasmonic gold NPs work as an electron mediator and therefore exhalt the photocatalytic efficiency of the ternary Au@TiO2/α-Fe2O3 photocatalyst. The present work delivers a novel perception to develop a stable photocatalyst based metal oxide/noble-metal hetero-nanostructure for the degradation of different types of pollutants in the industrial zones. [ABSTRACT FROM AUTHOR]

The Al2O3–SiO2-BFS (AS-BFS) solid adsorbent was developed from blast furnace slag (BFS). The potentiality of the AS-BFS for uranium ion removal from an aqueous medium, via the batch method, was explored and disused in terms of dynamic and isothermal properties. The sorbent exhibited good reusability, a high capacity for uranium ions, and a good specific surface area. The results showed that the sorbent evacuated uranium at about 88.5 mg/g. The sorbent represents a promising waste-derived substitute for other sorbents for water treatment. [ABSTRACT FROM AUTHOR]

Within the framework of the present study, a polydentate ligand with S and N donor sites along with its CuII‐based chelates were prepared and characterized. Elemental and thermal analyses, μeff and ΛM measurements as well as spectroscopy techniques including FT‐IR, electronic spectra, and EPR are the characterization tools. Computational chemistry calculations were applied to confirm the geometrical assignments of the penta and hexa coordinated perchlorato and chloro derivatives, respectively. Octahedral and trigonal bipyramidal stereochemistries were assigned for these copper(II) chelates. Powder X‐ray spectroscopy data were processed by Expo 2014 computer program for the structural illustration of one of the existing octahedral metal complexes. Biomimicking of copper(II) containing proteins phenoxazinone synthase and catechol oxidase was studied and the obtained results demonstrated promising oxidase‐like activity of the present CuII‐base complexes. Kinetic measurements were also performed to identify the potential catalytic pathways of the studied oxidation processes. The type of the counter‐anion included in the complexes significantly controls the structural features and the catalytic properties. [ABSTRACT FROM AUTHOR]

Summary: Nonfullerene acceptors (NFAs) have been recently explored to tune the organic dye‐sensitized solar cells. We designed three alkyl derivatives of NFAs from thiobarbituric acid (TBT1) decorated the triphenylamine featuring pyrrole unit (TPAP) to yield TPAP‐TBT1, TPAP‐TBT2, and TPAP‐TBT3 for the potential activity in solar cell applications. Density functional theory (DFT) calculations using B3LYP level of theory and b3lyp/6‐311g(d) basis set was used for the structures optimization. The TD‐DFT calculations were performed for the structures orbitals (HOMO and LUMO) calculations. The electronic structures of TPAP‐TBT2 derivative show the transethyl group on the structure, which facilitates the binding (−15.6 kcal/mol) to the semiconductor surface (TiO2) rather than the steric‐hindered N‐benzyl derivative (−13.1 kcal/mol). TBT alkyl substituents facilitate the intramolecular charge transfer within the dyes and improved the D‐π‐A electron mobility and the solar cell efficiency. The N‐ethyl and N‐benzyl derivatives showed better performance with respect to the calculated ΔGinject (−1.27) and (−1.22) and VOC values (1.45) and (1.40), respectively. [ABSTRACT FROM AUTHOR]

This experiment was done during 2019 and 2020 seasons on 10 years old Murcott tangerine trees (Citrus reticulata, Blanco) grafted on Volkamer lemon rootstock and grown under drip irrigation system at 3 × 5 m apart at a private citrus orchard at Sharkia Governorate, Egypt . The treatments were, Control treatment (sprayed with tape water only), Potassium silicate at 0.6 % (6 ml/ l), Aluminum silicate (Kaolin) at 4 %, Potassium silicate at 0.3 % (3 ml/l) + Aluminum silicate (Kaolin) at 2 %. The treatments were done at 3 weeks intervals from mid-May to mid-August. The spraying was over the whole tree (canopy and fruits). Generally, all silica treatments improved yield, fruit quality and reduced sunburned and splitted fruits. The combined treatment of kaolin at 2 % + potassium silicate at 0.3 % (3 ml/ l), was the best treatment. Where, it reduced the sunburned and splitted fruits and improved yield, fruit weight, fruit dimensions, peel thickness, TSS% in comparison with other treatments. It could be recommended as a treatment for Murcotte tangarine trees. [ABSTRACT FROM AUTHOR]

Two copper (II) complexes based on the mixed ligand system were synthesized and structurally characterized. The molecular formulae for complex (1), [Cu2L1L′] and complex (2), [CuL2L′] were determined based on analytical data, molar conductance, and thermal analysis results. The optimized structures of complexes (1) and (2) were determined by magnetic and spectroscopic measurements (FTIR, UV–Vis, and ESR) and confirmed by processing powder X‐ray diffraction data by Expo 2014 software. The geometry index (τ5), determined by ESR spectra and structural analysis based on powder X‐ray, demonstrates the square pyramidal geometry of the Cu (II) center of [Cu2L1L′] and [CuL2L′]. Cyclic voltammetry measurements were performed to elucidate the relationship between the redox properties of (1) and (2) and their oxidase‐mimicking catalytic activity. Catalytic aerobic oxidation of the polyphenols 3,5‐di‐tert‐butylcatechol (3,5‐DTBCH2), 4‐nitrocatechol, and 2‐aminophenol (2‐APH3) was studied by stopped‐flow technique. Promising catechol oxidase (COX) and phenoxazinone synthase (PHS) mimetic activity have been demonstrated for (1) and (2). Electrochemical data were used to determine the free energy (ΔG°) or driving force (−λ), and their correlation with the oxidase mimetic activity of(1) and (2) was examined. Several experimental procedures have been performed that have helped describe the catalytic mechanisms of the catalytic reactions taking place. [ABSTRACT FROM AUTHOR]

A field trial was conducted at Mallawi Agricultural Research Station, Minia Governorate, ARC, during 2016 and 2017 seasons in a high naturally infested field with charcoal rot and wilt diseases complex, as well as under artificially infestation with charcoal rot and wilt pathogens i.e. Macrophomina phaseolina and Fusarium oxysporum, respectively. The aim of this working to study the effect of intercropping guar with sesame at three planting densities of 100, 67 and 50% from sole guar and number of once and twice to reduce charcoal rot and wilt diseases complex, and yield and yield components of both crops. All intercropping patterns were significantly decreased disease incidence of charcoal rot and wilt diseases compared to the sole sesame under field and pots conditions. The intercropping 100% Sesame + 100% guar was the best pattern to reduce the incidence of charcoal rot & wilt disease complex in both seasons and pots experiment. Sesame seed yield/fad with guar at 50% plant density was increased by 32.66, 23.27% and 28.51, 18.58% than those of guar at of 100% and 67% in the 1 st and 2 nd, seasons, respectively. The highest value of total fresh yield/fad (ton) and total dry yield/fad (ton) of guar with sesame at intercropping pattern 100% guar were 5.91, 0.79 and 6.69, 0.69 ton/fad in the first and second seasons, respectively. Intercropping 50% guar with sesame and one cut guar recorded the highest values for LER, net return and MAI (monetary advantage index) in both seasons. Meanwhile, the lowest net return was recorded for intercropping 100% with two cuts of guar. Our study concluded that intercropping crop guar can be used for the protection of sesame charcoal- rot and wilt disease complex and produced greater seed yield than either crops grown alone. [ABSTRACT FROM AUTHOR]

Summary A newly synthesized zinc(II) complex, namely tert‐butyl N‐(2 mercaptoethyl)carbamatozinc(II) complex [Zn(Boc‐S)2] (Boc = tert‐butyl N‐[2‐mercaptoethyl]carbamate), has been used as an organozinc precursor for the production of crystalline ZnO and ZnO/TiO2 nanoparticles. The synthesized complex and the obtained nanomaterials were fully characterized using various spectroscopic and surface analysis techniques. Their surface morphology, chemical purity and stoichiometry have been investigated by scanning electron microscopy (SEM), energy dispersive X‐ray analysis (EDX) as well as X‐ray fluorescence. The synthesized Zn(II) molecular complex, ZnO and ZnO/TiO2 nanomaterials have been tested in alkaline aqueous solution (1.0 MNaOH) for the hydrogen evolution reaction (HER) using various electrochemical techniques. The results revealed high HER catalytic performance of ZnO and ZnO/TiO2 cathode materials, with the latter exhibiting higher catalytic activity recording an exchange current density (jo) of 0.3 mA cm−2. This current value, which approaches that of Pt wire (0.5 mA cm−2), cross‐sectional area ~0.008 cm2, is about 11 and 100 times greater than those measured for ZnO alone (0.028 mA cm−2) and TiO2 alone (0.0032 mA cm−2), respectively. Moderate catalytic activity was recorded for the complex catalyst, namely GC‐Zn(Boc‐S)2 with jo value of (0.01 mA cm−2). Tafel slope values of 130 and 122 mV dec−1 were calculated for ZnO and ZnO/TiO2, respectively. Such Tafel slope values, which are close to that of the Pt wire (120 mV dec−1), referred to a Volmer‐controlled HER kinetics. Other important electrochemical parameters describing the kinetics of the HER, such as roughness factor (Rf) and turnover frequency (TOF) were also estimated and discussed. The high numerical values of the various HER kinetic parameters recorded for the ZnO/TiO2 catalyst, in addition to its high stability and durability (stable for up to 10 000 continuous cathodic polarization cycles), besides maintaining its morphology and chemical composition after stability test (confirmed from SEM/EDX and XRD examinations), located it in a privileged position among the most efficient HER electrocatalysts reported in the literature. [ABSTRACT FROM AUTHOR]

Summary: In this work, PdO/TiO2 and Eu2O3/TiO2 nanocomposites (NCs) were synthesized using a new facile, template‐free, and one‐step solvothermal approach and characterized by several instrumentation techniques. X‐ray photoelectron spectroscopy studies revealed the presence of oxidized form of the Pd and Eu nanoparticles within the NC materials (PdO and Eu2O3). The two catalysts exhibited remarkable activity for the hydrogen evaluation reaction (HER) in a strong alkaline solution (4.0 M NaOH) with PdO/TiO2 catalyst being the best, which recorded an exchange current density (jo) of 0.26 mA cm−2 and a Tafel slope (βc) of 125 mV dec−1. Such parameters are not far from those recorded for a commercial Pt/C catalyst (0.71 mA cm−2 and 120 mV dec−1) performed here under the same operating conditions. Eu2O3/TiO2 catalyst recorded jo and βc values of 0.05 mA cm−2 and 135 mV dec−1. The Tafel slopes 125 and 135 mV dec−1 calculated on the PdO/TiO2 and Eu2O3/TiO2 catalysts suggest a HER kinetics controlled by the Volmer step. PdO/TiO2 catalyzed the HER with a high turnover frequency of 2.3 H2/s at 0.2 V versus the reversible hydrogen electrode, while Eu2O3/TiO2 catalyst only measured a turnover frequency value of 1.25 H2/s at the same overpotential. The two catalysts exhibited excellent stability and durability after 10 000 cycles and 72 hours of controlled potential electrolysis at a high cathodic overpotential, reflecting their practical applicability. Scanning electron microscope and X‐ray photoelectron spectroscopy examinations revealed that the morphology and chemistry of both catalysts were not altered as a result of the performed long‐term stability and durability tests. [ABSTRACT FROM AUTHOR]

Abstract This work presents a modified solvothermal process for a facile synthesis of high thermally stable nanocrystalline anatase TiO 2 NPs doped with Cu 2 O NPs. A Z -scheme mechanism was used to account for the enhanced photocatalytic activity exhibited by these materials. Also, the nanocomposite was impregnated in cotton fabric to obtain a modified fiber with high thermal stability, self-cleaning, enhanced UV protection, and antibacterial activity. The as-prepared nanomaterials and the coated fabric were characterized by various physicochemical techniques such as XRD, EDXRF, TGA, TEM, HRTEM, and SEM. The Cu 2 O/TiO 2 molar ratio in the nanocomposite was found to possess a pronounced impact on the crystalline structure, size and morphology of TiO 2 NPs. The XRD revealed proper substitutions of the few Ti4+ sites by Cu2+ ions in TiO 2 host lattice. Optical measurements showed that the plasmonic peak of the Cu 2 O/TiO 2 nanocomposite was affected by the copper-doping concentration, enhancing self-cleaning of Cu 2 O/TiO 2 under direct sunlight. The TiO 2 /fiber self-cleaning efficiency (12 h for MB removal) was increased by the in situ growing of Cu 2 O (5.5 h). Antibacterial activity studies revealed high potential activity of Cu 2 O/TiO 2 against both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli , Kleissella pneumonia, Saccharomyces sp.) bacteria. The promising photocatalytic and biocidal activity of our synthesized Cu 2 O/TiO 2 nanocomposites was ascribed to the reactive oxygen species generated by the Z -scheme mechanism under direct Sunlight. Graphical abstract Unlabelled Image Highlights • Facile synthesis of highly thermal stable Cu 2 O/TiO 2 by solvothermal method. • Fabrication of cotton fiber coated with Cu 2 O/TiO 2 • The coated cotton fiber possesses efficient self-cleaning, UV protection and antibacterial activities. • Z -scheme mechanism was proposed for the TiO 2 photocatalytic activities enhancement by Cu 2 O doping under sunlight irradiation. [ABSTRACT FROM AUTHOR]

Abstract We report here a facile, template-free and one-step solvothermal approach for the synthesis of high-temperature stable gold/titania nanocomposite (NCs), providing a new, simple, quick and inexpensive wet-chemical route. Our approach is based on the assembly of gold salt and titanium butoxide in dimethyl sulfoxide (DMSO). Also, we present here, for the first time, a cathodically activated Au/TiO 2 catalyst with Pt/C activity for the hydrogen evolution reaction (HER) in 0.5 M H 2 SO 4 in the dark. The as-prepared (unactivated) Au/TiO 2 NCs exhibits considerable electrocatalytic activity for H 2 generation in the dark, with a low onset potential (E HER) of −64 mV vs. RHE, a Tafel slope (- b c) of 60 mV dec−1 and an exchange current density (j o) of 0.12 mA cm−2. Long-term stability and durability tests in 0.5 M H 2 SO 4 , employing cyclic voltammetry technique (10,000 of repetitive cycling) and 72 h of chronoamperometry measurements at a high cathodic potential (cathodic activation), reveal that the electrocatalyst activates during such aging processes yielding an activated Au/TiO 2 catalyst with Pt/C-like activity for H 2 generation (E HER -3 mV, - b c : 35 mV dec−1, and j o : 0.95 mA cm−2). The outstanding HER activity of the activated catalyst is discussed. [ABSTRACT FROM AUTHOR]

Purpose Approximately 348,000 ventral hernia repairs are performed annually in the United States and the incisional hernia recurrence rate is approximately 20% as a result of suture and mesh device failure. Device failure is related to changes at the suture/tissue interface that leads to acute or chronic suture pull-through and surgical failure. To better manage mechanical tension, we propose a modified mesh design with extensions and demonstrate its mechanical superiority. Methods Comparative uniaxial static tensile testing was conducted on polypropylene suture and a modified mesh. Subsequently, a standard of care (SOC) mesh and modified mesh were evaluated using a tensometer in an acute hernia bench-top model. Results Modified mesh breaking strength, extension knot breaking strength, extension disruption, and extension anchoring were superior to suture (p < .05). Modified mesh ultimate tensile strength of anchoring was superior to SOC mesh (p < .05). Various stitch patterns and modifications in device design significantly improved device tension-free performance far beyond clinically relevant benchmarks (p < .05). Conclusions Testing demonstrates that the modified mesh outperforms SOC mesh and suture in all tested failure modes. SOC hernia mesh tears through tissue at stress levels below maximum physiologic stress, whereas, the modified hernia mesh is up to 200% stronger than SOC mesh at resisting suture tearing through tissue and maintains anchoring at stresses far beyond clinically relevant benchmarks. Modifying hernia mesh design significantly improves device mechanical performance and enhances tension-free repair. [ABSTRACT FROM AUTHOR]

The amount of currently available freshwater on earth is in continuous decline due to rapidly increased consumption as a result of population growth, industrial use and climate change. Now, it is imperative to look for better approaches to increase the freshwater available to meet the developing requirement for water. Here, we synthesised TiO2 doped 3%La3+ and 3%Ce3+ nanoparticles (NPs) by a modified solvolysis process in Dimethyl Sulphoxide (DMSO) to enhance wastewater treatment. The structure and morphology of the undoped and La3+ or Ce3+-doped TiO2 nanoparticles (NPs) were characterized by powder X-ray diffraction (XRD), Transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), Energy‐dispersive X‐ray fluorescence spectrometer (EDXRF), thermogravimetric analysis (TGA-DTA), and Fourier transmission infrared (FT-IR). The results reveal the substitution of both La3+ and Ce3+ (3.0%) in the TiO2 anatase lattice forming a homogeneous solid, high‐thermally stable NPs, free from organic compounds and any oxide byproducts. The 3%La3+/TiO2 NPs were able to mitigate more than 84% and 69% of F− and PO43- respectively. On the other hand, 3%Ce3+/TiO2shows better performance for Cr3+, Fe2+, Mn2+, Pb2+removal % of 96.9, 94, 98.7, 100, respectively. [ABSTRACT FROM AUTHOR]

A new chlorobis(2-aminomethylbenzimidazole)zinc(II) perchlorate complex [Zn(AMB) 2 Cl](ClO 4 ) 1 has been synthesized and characterized. Spectral and X-ray structural features led to the conclusion that the zinc(II) complex has a square-pyramidal environment around zinc(II) center with coordination chromophore ZnN 4 Cl. Different amounts of complex 1 were supported on glassy carbon (GC) electrode yielding three GC-supported complex 1 electrodes with different loading densities (0.2, 0.4, and 0.8 mg cm −2 ). These electrodes were tested as molecular electrocatalysts for the hydrogen evolution reaction (HER) in phosphate buffer aqueous solutions (pH 7), employing linear sweep voltammetry (LSV) and electrochemical impedance spectroscopy (EIS). Results showed that GC-complex 1 catalysts are highly active for the HER, and this catalytic activity enhances with the loading density. The one with the highest loading density (0.8 mg cm −2 ) exhibited high HER catalytic activity with low onset potential of −140 mV vs. RHE and a high exchange current density of 0.22 mA cm −2 . It required an overpotential of 240 mV to achieve a current density of 10 mA cm −2 . It also recorded a turnover frequency (TOF) of 1722 mol of hydrogen per mole of catalyst per hour at overpotential 500 mV, which is comparable with the most active molecular electrocatalysts reported in the literature for H 2 generation from aqueous neutral solutions. A catalytic cycle is proposed for the generation of hydrogen by complex 1 and the mechanism of the HER is discussed based on the measured Tafel slope (140 mV dec −1 ). [ABSTRACT FROM AUTHOR]

Two oxovanadium(IV) complexes, viz., [VO(Me-IDA)(H 2 O) 2 ] ( 1 ) and NaH[VO(EDTA)]·4H 2 O ( 2 ) (Me-IDA = methyliminodiacetic acid and EDTA = ethylenediaminetetraacetic acid) have been synthesized and characterized by FT-IR, UV–Vis, mass spectrometry, elemental analysis, magnetic moment and thermal analysis, as well as electrochemical measurements including cyclic voltammetry. Both compounds are monomeric with distorted octahedral geometries. Compound 2 has been structurally characterized by using X-ray crystallography. It shows an octahedral V(O)N 2 O 3 coordination geometry, which exhibits chemically significant hydrogen bonding interactions besides showing coordination polymer formation. Compounds 1 and 2 show an irreversible redox peak around +0.80 V versus Ag/AgCl corresponding to one-electron oxidation of V(IV) to V(V). The free radical scavenging activity of compounds 1 and 2 were done using 2,2-diphenyl- 1-picrylhydrazyl (DPPH). Both compounds have shown encouraging ROS scavenging activities. The cytotoxicity effects of both compounds toward two different tumor cells (HePG2 and MCF-7) have been also studied by MTT assay. The IC 50 values obtained, after 48 h incubation at 37 °C for HepG2 and MCF-7 cell lines were 74.23 and 42.04 μg/mL for compound 1 and 65.56 and 48.34 μg/mL for compound 2 , respectively. Conclusively, the present investigation provides preliminary results which suggest that such compounds can be promising alternative antitumor agents. [ABSTRACT FROM AUTHOR]

Herein, we report the one-pot cyclization of Biginelli Adduct, ethyl 4-(2-hydroxyphenyl)-6-methyl-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carboxylate ( I) to the oxygen-bridged adduct, ethyl 2-methyl-4-thioxo-3,4,5,6-tetrahydro-2 H -2,6-methanobenzo[ g ] [1,3,5]oxadiazocine-11-carboxylate ( II) in a high yield and purity under mild reaction condition using zinc(II) perchlorate hexahydrate as a highly efficient catalyst. The cyclic product ( II ) was characterized both in the solid state and in solution using FT–IR, 1 H NMR, and UV–visible spectroscopy. Theoretical calculations using density functional theory with B3LYP/6-311++G(d,p) level were used to further investigate the structure properties. DFT calculations (gas phase) revealed the stability of cyclic compound II (3.45 kcal/mol) than compound I . In addition, the anticancer activity of II was investigated using MCF-7 human breast cell line. The results revealed a moderate activity with 223.55 μg/ml IC 50 value. [ABSTRACT FROM AUTHOR]

A series of mixed-ligand complexes, viz., [CuLL'X]Y {L = bipyridine; L' = glycine; X = 0, Y = ClO 4 − ( 1 ); X = Cl, Y = 2H 2 O ( 2 ); X = H 2 O, Y = NO 3 − ( 3 ); X = CH 3 COO − , Y = H 2 O ( 4 )} and {[Cu(Gly)(BPy)] 2 -μ-(SO 4 )}( 5 )} have been synthesized and characterized by means of elemental analysis, spectroscopic (FT–IR, UV–Vis and ESR), and thermal analysis, as well as magnetic moment measurements. Spectral and X-ray structural features led to the conclusion that complexes 2 – 5 have square-pyramidal environments around copper(II) center with coordination chromophores CuN 3 OCl and CuN 3 O 2 , respectively. Whereas complex 1 displays square planar geometry. The quasi-reversible Cu II /Cu I redox couple slightly improves its reversibility with considerable decrease in current intensity. Additionally, the antioxidant ( superoxide dismutase and catalase ) biomimetic catalytic activities of the obtained complexes have been tested and found to be promising candidates as dual functional mimic enzyme to serve for complete reactive oxygen species (ROS) detoxification, both with respect to the superoxide radicals and the related peroxides. [ABSTRACT FROM AUTHOR]

Field experiments were conducted in cotton fields, Gossypium barbadense L. variety Giza 86 at Zagazig District, Sharkia Governorate, Egypt during 2014 season. Four programs were applied with three respective sprays for each using commercial formulation of garlic extract Nat-108 and varied as spray start times and interval periods towards the development of more environmentally sound technologies for management of cotton aphids (Aphis gossyppii), cotton thrips (Thrips tabaci), sweet potato whitefly (Bemesia tabaci), spider mites (Tetranychus spp.), leafhoppers (Empoasca spp.), green stink bug (Nezara viridula), pink bollworm (Pectinophora gossypiella) and cotton leafworm (Spodoptera littoralis). In addition to the side effects on several predators species found in cotton fields associated with cotton pests, such as, coccinellids, chrysopids, staphylinids, anthocorid, dipterous and true spiders were studied. Results, educed that the commercial formulation of garlic extract at the rate of 1 litter/100 litter water showed relatively high efficiency against aphids, leafhoppers and thrips, with maximum reduction percentages of 81.33, 82.51 and 84.12%, respectively; moderate efficiency against pink bollworm, whitefly, spider mites, green stink bug with maximum reduction percentages of 61.50, 78.89, 67.56 and 54.46%, respectively and low efficacy against predators except at the end season where the relatively highest reduction percentage was 62.91%, while it was less effective against the cotton leaf worm ranged 23.30-25.80% reduction in comparison with 70.56-90.00% reduction in cotton leafworm population for Dursban (chloropyrifose). So, the garlic extract cannot considered as a botanical pesticide against S. littoralis under cotton field conditions at Sharkia Governorate but needs more studies to evaluate its efficacy on different levels of S. littoralis infestation and stags. In regard to the programs results for garlic extract efficacy, it cleared that the first program tended to be the highest sustainable control of aphids, whitefly, thrips and spider mites on cotton plants, where the sprays started just after cotton plants emergence, whereas the numbers of pests were very low while the third program where the sprays started after 20 days of cotton plants emergence was tended to be the highest sustainable control of leafhoppers. In case of N. viridula, it could be decided that the organophosphorous pesticide, Dursban can be used as effective insecticide especially at the end season period. Finally, garlic extract was tended to be safe to predators especially throughout its effective activity period during the period from seedling to the end of growing season of cotton plants that confirmed by the results of the third program which ranged 2.57-21.46% reduction percentages in predators population. So, garlic extract could be recommended to be used effectively against cotton aphids, leafhoppers, cotton thrips and pink bollworm in IPM program of cotton pests in cotton fields. The organophosphorous compound, Dursban can be considered as good control pesticide against tested pests recorded reduction percentages ranged 56.99-96.99% but caused serious damage to associated predators on cotton plants at the end of season period recorded reduction percentages reached to 99.76% that disturbed the natural balance in cotton cultivation area environment. [ABSTRACT FROM AUTHOR]

Anatomical, physiological, and functional connectivity exists between the neurons of the primary motor cortex (M1) and spinal cord. Paired associative stimulation (PAS) produces enduring changes in M1, based on the Hebbian principle of associative plasticity. The present study aimed to establish neurophysiological changes in human cortical and spinal neuronal circuits by pairing noninvasive transspinal stimulation with transcortical stimulation via transcranial magnetic stimulation (TMS). We delivered paired transspinal and transcortical stimulation for 40 min at precise interstimulus intervals, with TMS being delivered after (transspinal-transcortical PAS) or before (transcortical-transspinal PAS) transspinal stimulation. Transspinal-transcortical PAS markedly decreased intracortical inhibition, increased intracortical facilitation and M1 excitability with concomitant decreases of motor threshold, and reduced the soleus Hoffmann's reflex (H-reflex) low frequency-mediated homosynaptic depression. Transcortical-transspinal PAS did not affect intracortical circuits, decreased M1 excitability, and reduced the soleus H-reflexpaired stimulation pulses' mediated postactivation depression. Both protocols affected the excitation threshold of group Ia afferents and motor axons. These findings clearly indicate that the pairing of transspinal with transcortical stimulation produces cortical and spinal excitability changes based on the timing interval and functional network interactions between the two associated inputs. This new PAS paradigm may constitute a significant neuromodulation method with physiological impact, because it can be used to alter concomitantly excitability of intracortical circuits, corticospinal neurons, and spinal inhibition in humans. [ABSTRACT FROM AUTHOR]

The intermolecular charge transfer CT-complexes of tris(2-aminoethyl)amine (TREN) with different π-acceptors such as picric acid (PIC), o-chloranil (CHL) and tetracyanoquinolines (TCNQ) were investigated in both solid and liquid phase. Spectroscopic techniques, such as FT-IR, 1 H NMR, 13 C NMR, and UV–vis, were used to characterize the molecular complexes. Spectral data, for example, formation constants, molar extinction coefficient, standard free energy, and ionization potentials for the complexes were calculated for the 1:1 molecular CT-complexes. Exploring the single crystal of TREN/PIC, grown by slow evaporation technique from methanol solution at room temperature, shows that CT-complex stabilized by two noncovalent interactions, namely, hydrogen bond and dipole–dipole interactions. In addition, the structure of tris(2-aminoethyl)amine and CHL and TCNQ complexes were investigated by DFT calculations at B3LYP/6-311 ++G(d,p) level of theory. [ABSTRACT FROM AUTHOR]

A series of albendazole-based copper(II) complexes with different counter anions, [Cu(Albz)(H2O)2](ClO4)2(1), [Cu(Albz)2(Cl)]Cl·2H2O (2), [Cu(Albz)2(NO3)](NO3) (3), and [Cu2(Albz)2(μ-SO4)2(H2O)2] (4) (Albz = albendazole), have been synthesized and characterized. Their structures and properties were characterized by elemental analysis, thermal analysis (TGA, DTG and DTA), IR, UV–vis and ESR spectroscopies, cyclic voltammetry, electrical molar conductivity, and magnetic moment measurements. A square-planar geometry is proposed for1, whereas the five-coordinate copper(II) complexes2,3, and4have a square pyramidal geometry. Theoretical calculations (DFT) using B3LYP/6–311 + G(d,p) level of theory corroborated the experimental results to investigate both the drug Albz and its copper(II) complex,1. The hepatoprotective and antioxidative efficacy of Albz and1–4were evaluated against carbon tetrachloride-induced acute hepatotoxicity in rats. Hepatotoxicity in experimental rats was evidenced by significant decrease in the antioxidant enzyme activities (SOD, GSH-S-transfers, and GSH-Rd levels). The results have strong impact for designing anticancer drugs, combined with their potential cytotoxic and antioxidant activities, which can be targeted selectively against cancer cells and increase their therapeutic index and advantages over other anticancer drugs. The DNA cleavage studies of Albz and its copper(II) complexes using genomic DNA indicated that Albz has no role in cleavage of DNA, and only1played a marked role in the DNA cleavage without any external additives. [ABSTRACT FROM AUTHOR]

Interaction of copper(II) perchorate hexahydrate with metformin as a primary ligand and amino acids as secondary ligands lead to the formation of three mixed ligand complexes, viz., [Cu(Met)(AA)(ClO4)(H 2 O)] (Met = metformin, AA = glycine (1) , L-glutamine (2) , and L-arginine (3) ). Their structures and properties were characterized by elemental analysis, IR, UV–Vis, and ESR spectroscopy, electrochemical measurements including cyclic voltammetry, electrical molar conductivity and magnetic moment measurements. An octahedral geometry is proposed for the three compounds in monomeric structures. The redox behavior of complexes was investigated by cyclic voltammetry. Also, the interaction of copper complexes with calf thymus double-stranded DNA (CT-DNA) was studied electrochemically by using CV. The binding constants of complexes (2) and (3) with DNA were determined through the changes on the redox peak currents. The binding constants were evaluated to be 4.6 × 10 4 and 2.8 × 10 4 M − 1 for complexes (2) and ( 3) , respectively. Additionally, the antioxidant ( superoxide dismutase and catalase ) biomimetic catalytic activities of the obtained complexes (1 – 3) have been assessed for their efficiency of O 2 − scavenging with and complete reactive oxygen species (ROS) detoxification with respect to peroxides. [ABSTRACT FROM AUTHOR]

• Synthesis and Characterization of MSAC. • Studies adsorption of Doxorubicin Hydrochloride at MSAC. • Studying the mechanism of adsorption and rate controlling steps. • Statistical and physical simulation. The mango seeds activated carbon (MSAC) nanoparticles were created because these materials have high biocompatibility and might be used as a medication carrier. The anti-cancer medication doxorubicin hydrochloride (DOX) was loaded on MSAC nanoparticles in this study was characterized by the XRD, SEM, and BET showed that the surface area being 443 m2/g while pore volume was 0.649 cm3/g. The doxorubicin technique was applied performance factors, contact period, pH, concentration, adsorbent dose, and temperature were all examined to evaluate DOX adsorption. Greatest DOX adsorption on MSAC found to be at a pH of 5. This shows that, because to the outstanding components employed in the MSAC structure, the existing difficulty of employing larger doses of doxorubicin could be effectively mitigated. The created approach significantly enhanced DOX adsorption, indicating that the produced nanocomposite might be used to deliver drugs. The adsorption process of MSAC was at its optimum of 0.25 mmol/g, and the adsorption isotherm fit to the Langmuir model, while fitted to pseudo-second-order model for adsorption kinetics. DOX adsorption on MSAC is endothermic and spontaneous, according to thermodynamic studies. [ABSTRACT FROM AUTHOR]

A new vanadate compound, which contains interlamellary, the insulin enhancing agent metformin was prepared. Its structure was established to be [Metformin] 2 [V 2 O 6 ]·H 2 O 1 by using elemental analysis, FT-IR and 1 H– 13 C NMR spectroscopic methods. The crystal structure of 1 shows that each of the two vanadium atoms is coordinated to four oxygen atoms, forming a distorted tetrahedral {VO 4 } that are arranged alternately to form one-dimension { V 2 O 6 } n 2 n − chains. The chains are stabilized by an extensive hydrogen bonding involving oxide ligands of the chains and metformin molecules which fill the space between the stacks of chains. Furthermore, powder X-ray diffraction, EDX-SEM and TGA-DTA analysis of compound 1 are also investigated, which demonstrates its high purity and thermal stability. The thermoanalytical data evidence that compound 1 undergo complete decomposition, resulting in V 2 O 5 as a residual product. Investigation of the glucose lowering activity by oral administration of compound 1 in streptozotocin-induced diabetic rats was examined. [ABSTRACT FROM AUTHOR]

The molecular complex between 1-(2-methoxyphenyl)-1H-imidazole-2(3H)-thione (Hmim OMe ) and iodine (I 2 ) was investigated. Single crystal of [(Hmim OMe ) I 2 ] adduct was grown by slow evaporation technique from chloroform at room temperature. Spectroscopic techniques such as FT-IR and Raman techniques, as well as elemental and thermal analysis were used to characterize the complex. The crystal structure shows that the formed adduct stabilized by two noncovalent interactions, namely, hydrogen bond (HB) and halogen bond (XB). Orthogonal HB/XB associated with iodine atom (I) was observed and fully characterized. The ability of iodine to behave as hydrogen bond acceptor and halogen bond donor was held responsible for the orthogonal HB/XB presence. In addition, the structure of Hmim OMe I 2 was investigated theoretically using MP2/aug-cc-pVDZ level of theory. Natural bond orbital analysis (NBO) was used to investigate the molecular orbitals interactions and orbitals stabilization energies. [ABSTRACT FROM AUTHOR]

A dithiolate-containing a carbamate mononuclear cobalt(II) complex namely, [Co(Boc-S) 2 ] ( 1 ), was obtained by the reaction of a methanolic solution of cobalt(II) nitrate hexahydrate with two equimolar amounts of the deprotonated form of tert -butyl N -(2-mercaptoethyl)carbamate (Boc-SH). The cobalt(II) complex ( 1 ) was characterized in the solid state and in solution by using FT–IR, Raman, UV–visible, and EI–mass spectroscopies, as well as thermal and X-ray diffraction studies. Spectral data showed that the carbamate (Boc-SH) acts as a mono-anionic bidentate ligand coordinating the cobalt(II) ion through two imine nitrogen and two deprotonated thiolate sulfur donor atoms in a distorted tetrahedral geometry. The thermoanalytical data evidence that the complex is stable up to 165 °C and undergoes complete decomposition, resulting in CoO. TEM imaging of the oxide residue shows its nano size clusters, suggesting that the complex ( 1 ) may be used as a precursor for nano-oxides. X-ray powder diffraction patterns evidence an isomorphism among the complex. The redox behavior of the cobalt(II) complex was also investigated by cyclic voltammetry. The reaction of the dithiolate cobalt(II) complex ( 1 ) with methyl iodide appears to occur intramolecularly with the cobalt-bound dithiolate, forming the cobalt(II)-bound dithioether complex [Co(Boc–SCH 3 ) 2 ]I 2 ( 2 ), as a dication complex with a clean second-order reaction of 13.24 × 10 −2 M −1 ·s −1 . [ABSTRACT FROM AUTHOR]

Highlights: [•] Pt/TNT-MWCNT nanocomposite was synthesized via hydrothermal-deposition method. [•] Pt/TNT-MWCNT had higher adsorption and visible light activity than Pt/TNT and Pt/graphene. [•] The difference in activity between Pt/TNT-MWCNT and Pt/graphene was well evaluated. [ABSTRACT FROM AUTHOR]

Highlights: [•] Two dithiolate complexes were synthesized as models of thiolte alkylating enzymes. [•] The spectral techniques suggest that both complexes have square planar geometries. [•] The nickel(II) dithiolte complex may be used as a precursor for nanooxide formation. [•] The methylation reaction appears to occur intramolecularly at the metal-bound dithiolate. [ABSTRACT FROM AUTHOR]

Highlights: [•] Syntheses of four nickel complexes, derived from 5,5-diethylbarbiturate. [•] The spectral techniques suggest that all nickel(II) complexes exhibit octahedral geometry. [•] The low electrical conductance of the complexes supports their neutral nature. [•] This study is making attention for both the spectroscopic and biological applications. [ABSTRACT FROM AUTHOR]

Two new ligands, 4-hydroxy coumarin-3-thiosemicarbazone (H 2L 1) and 4-hydroxy coumarin-3-semicarbazone (H 2L 2) were synthesized and used for the preparation of a series of transition metal complexes (Cr 3+, Co 2+, Ni 2+, Cu 2+, and Fe 3+), derived from these ligands. These complexes have the forms [ML 1Cl 2]· nX ( 1– 5) and [ML 2Cl]· nX ( 6– 9) (X = H 2O or ethanol). The structures of these complexes were elucidated by elemental analyses, IR, UV–Vis, and electrical conductivity, as well as magnetic susceptibility measurements and thermal analyses. IR spectral data indicates that in all complexes, the ligands act as monobasic tridentate, coordinated through keto oxygen or sulfur, azomethine nitrogen and deprotonated phenolic oxygen atom. On the basis of other physicochemical investigations, tetrahedral or square planar geometries are assigned for Cu 2+ complexes in monomeric structures. In the case of the Co 2+, Ni 2+ and Fe 3+ complexes, octahedral stereochemistries in monomeric structures are suggested. The dissociation constants of the ligands and the stability constants of their Cu(II), Co(II), Ni(II), and Fe(III) complexes have been also determined using potentiometric pH-metric titration in mixed solvents of dioxane: H 2O and DMF: H 2O with different ratios and different temperatures. [ABSTRACT FROM AUTHOR]

Abstract: Solution studies of the tetradentate ligand tris(2-benzylaminoethyl)amine, BzTren with both zinc(II) and copper(II) salts were investigated in aqueous methanol (33% v/v) by means of 1H NMR, potentiometric, and UV-visible titrations as well as cyclic voltammetry. Subsequently, their zinc(II) and copper(II) complexes [BzTren-M(OH2)]2+ 1 and 2 (M2+ =Zn2+ and Cu2+) were synthesized and fully characterized by using FT-IR spectroscopy, elemental analysis, and thermal analysis. Complexes 1 and 2 are investigated kinetically for the catalytic hydrolysis of the toxic organophosphate parathion at 50°C in aqueous methanol (33%, v/v). The kinetic results indicate that copper(II) complex 2 is more active than zinc(II) complex 1, presumably a reflection of the effective electron-withdrawing as well as the greatest electrophilicity of copper(II) ion. [Copyright &y& Elsevier]

Abstract: A template condensation of α-diketones (biacetyl, benzile and 2,3-pentanedione) with 2-methyl-3-amino-(3H)-quinazolin-4-one (AMQ) in the presence of CuX2 (X=Cl−, Br−, or ) resulted in the formation of tetradentate Schiff base copper(II) complexes of the type [CuLX]X and [CuL]X2. Structural characterization of the complex species was achieved by several physicochemical methods, namely elemental analysis, electronic spectra, IR, ESR, molar conductivity, thermal analysis (TAG & DTG), and magnetic moment measurements. The stereochemistry, the nature of the metal chelates, and the catalytic reactivity are markedly dependent upon the type of counter anions and the ligand substituent within the carbonyl moiety. A square planar monomeric structure is proposed for the perchlorate, nitrate, and bromide complexes, in which the counter anions are loosely bonded to copper(II) ion. For the chloride complexes, the molar conductivities and the spectral data indicated that they have square-pyramidal environments around copper(II) center. The reported copper(II) complexes exhibit promising tyrosinase catalytic activity towards the hydroxylation of phenol followed by the aerobic oxidation of the resulting catechol. A linear correlation almost exists between the catalytic reactivity and the Lewis-acidity of the central copper(II) ion created by the donating properties of the parent ligand. The steric considerations could be accounted to clarify the difference in the catalytic activity of these functional models. [Copyright &y& Elsevier]

Abstract: Interaction of the tridentate ligand bis(2-picolyl)amine L with copper(II) salts gave a series of copper(II) complexes with the formula types: [LCu(X)2] (X=Cl− 1,=Br− 2), [(LCu(H2O)(μ-SO4)(LCu(H2O)]SO4 3, [LCu(OAc)](OAc)H2O 4, [LCu(H2O)2](Y)2 (Y= 5,= 6). Their structures and properties were characterized by elemental analysis, thermal analysis (TGA), IR, UV–vis and ESR spectroscopy, electrochemical measurements including cyclic voltammetry and electrical molar conductivity, and magnetic moment measurements. A square pyramidal geometry is proposed for the halogeno complexes 1 and 2 in monomeric structures. For sulfate complex, the sulfate group bridged two copper(II) ions of the two [N3O] donor units to give the dimeric complex molecule 3 in square pyramidal environment around the copper(II) ions. In the case of complexes 4–6, square planar stereochemistries in monomeric structures are suggested. The SOD biomimetic catalytic activity of the obtained complexes was assessed for their ability to inhibit the reduction of nitroblue tetrazolium (NBT). The catalytic efficiency of scavenging by complexes depends on the nature of the particular acidic anion radical incorporated in the complex molecule and follows the order: > >Br- ⩾Cl− > >AcO−. A probable mechanistic implications for the catalytic dismutation of by copper(II) complexes are proposed. Furthermore, complex 1 exhibits significant hydrolytic cleavage of the genomic DNA in the absence of any external additives. In addition, the in vitro study of cytotoxicity of complex 1 on colon cancer cell line (Caco-2) indicates that the complex has the potential to act as an effective anticancer drug with IC50 value of 156±0.35μM. [Copyright &y& Elsevier]

Abstract: The inhibitive action of a newly synthesized glycine derivative, namely 2-(4-(dimethylamino)benzylamino)acetic acid hydrochloride (GlyD) on pitting corrosion of Al in KSCN solutions was studied. Obtained results were compared with glycine (Gly) itself. Cyclic polarization, potentiostatic and galvanostatic measurements were made, complemented with ex situ scanning electron microscope (SEM) examinations. Cyclic polarization measurements indicated that the presence of Gly and GlyD in aggressive SCN- solutions shifted the pitting potentials to more noble values and decreased the anodic currents in the passive region. Transient studies showed that nucleation of pit takes place after an incubation time (t i). The rate of pit nucleation (t i −1) and growth was found to decrease to an extent depending on the type inhibitor. The SEM images showed that the severity of the pitting corrosion of Al in KSCN solution decreased to an extent depending on type of inhibitor. GlyD was much better than Gly in controlling pit initiation and growth of Al in these solutions. [Copyright &y& Elsevier]

Abstract: The reaction of the tetradentate ligand N,N-bis(2-picolyl)glycine, BPG-H, which was successfully synthesized in its free state, with the nitrate or perchlorate salts of both zinc(II) and copper(II) ions yielded the aqua complexes [BPG-Zn(H2O)2]X 1, 2 and [BPG-Cu(H2O)2]X 3, 4 (X= for 1 and 3 and X= for 2 and 4). Two intermediate complex species, namely the bridged copper(II) hydroxo {[(BPG)Cu]2(μ-OH)2} 5 and zinc(II)-bound diethylphosphate ([BPG-Zn(OPO(C2H5)2] 6 were successfully isolated in good yields and pure forms. The ligand and its complexes were characterized by using elemental analyses, FT-IR, and thermal analyses as well as in solution by using conductometric, UV–visible, pH, and 1H NMR titrations. All complexes have basically similar coordination chromophor (N3O3) through the coordination of the ligand with both zinc(II) and copper(II) metal ions. The hydrolase biomimetic catalytic activity of complexes 1 and 3 were examined towards the toxic organophosphate, paraoxon (p-NPDEP). The results indicate that the obtained bell-shaped curves of pH-rate below pH 8.6 mirrors the ionization curves of the coordinated water molecules to give the hydroxoaqua complexes and provide strong evidence that these are the catalytically active species in the hydrolysis reactions. [Copyright &y& Elsevier]

Abstract: A newly synthesized glycine derivative (GlyD1), 2-(4-(dimethylamino)benzylamino)acetic acid hydrochloride, was used to control mild steel corrosion in 4.0M H2SO4 solutions at different temperatures (278–338K). Tafel extrapolation, linear polarization resistance (LPR) and impedance methods were used to test corrosion inhibitor efficiency. An independent method of chemical analysis, namely ICP-AES (inductively coupled plasma atomic emission spectrometry) was also used to test validity of corrosion rate measured by Tafel extrapolation method. Results obtained were compared with an available glycine derivative (GlyD2) and glycine (Gly). Tafel polarization measurements revealed that the three tested inhibitors function as mixed-type compounds. The inhibition efficiency increased with increase in inhibitor concentration and decreased with temperature, suggesting the occurrence of physical adsorption. The adsorptive behaviour of the three inhibitors followed Temkin-type isotherm and the standard free energy changes of adsorption () were evaluated for the three tested inhibitors as a function of temperature. The inhibition performance of GlyD1 was much better than those of GlyD2 and Gly itself. Results obtained from the different corrosion evaluation techniques were in good agreement. [ABSTRACT FROM AUTHOR]

Abstract: The tripod ligand tris(2-benzimidazolylmethyl)amine L1 and its methylated derivative tris(N-methyl-2-benzimidazolylmethyl)amine L2 were used for the preparation of chloro complexes [L1 Zn–Cl](PF6) 1 and [L2 Zn–Cl](PF6) 2. These complexes reacted with AgPF6 in aqueous acetone to form the corresponding aqua complexes [L1 Zn–OH2](PF6)2 3, [L2 Zn(H2O)](PF6)2 4, which were deprotonated by using KOH to form the hydroxide complexes [L1 Zn–OH)](PF6) 5 and [L2 Zn–OH)](PF6) 6. 1H NMR titration of the ligands with Zn(II) ions gave detailed information about the structure of the resulting zinc complexes and the evidence for the existence of the zinc-bound hydroxo species. Complex 3 reacted with CO2 gas in the presence of triethylamine to give the bicarbonate complex [L1 Zn–OCO2H)](PF6), which was characterized by IR and 13C NMR spectroscopes. The X-ray structure of [L1 Zn–NCS]2[Zn(NCS)4] 7 as structural carbonic anhydrase inhibitor was determined and adopted slightly distorted tetrahedral ZnN4 coordination geometries with the equatorial positions occupied by three benzimidazole nitrogen atoms and apical position by nitrogen atom from the thiocyanate anion. [Copyright &y& Elsevier]