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Climbing the ladder of density functional approximations has long been proposed to systematically improve the accuracy of first-principles calculations employing the density functional theory (DFT); however, up until now, the Perdew–Burke–Ernzerhof (PBE) functional at the second rung of the ladder, has dominated. Here, we present a study of the martensitic phase transition in NiTi based on ab initio molecular dynamics simulations and thermodynamic integration using the third-rung approximation of the strongly constrained and appropriately normalized (SCAN) meta-generalized gradient approximation (GGA). Although the predicted equilibrium lattice constants and formation enthalpy agree well with experimental data, the martensitic transition temperature (MTT) is overestimated by 94% (or 324 K too high), compared with only 22% (77 K) overestimation by PBE. The latent heat (q) is severely overestimated by SCAN as well. This deteriorated performance originates from the enlarged energy difference (ΔE) between the austenite and martensite phases, compared with the PBE result. Furthermore, a large variation (over 50 meV/atom) in ΔE using different meta-GGAs indicates large variations in computed MTTs (∼ 400 − 500 K) and q, i.e., the predicted thermodynamic properties depend sensitively on the choice of meta-GGA. This would pose a serious problem when upgrading DFT calculations to the third rung. One possible solution is to add NiTi as a norm system so that the revised SCAN meta-GGA could reproduce the PBE results of the relevant energy difference. [ABSTRACT FROM AUTHOR]

Phosphoryl podands of neutral type with a flexible ethylene glycol chain and diphenylphosphorylmethyl end groups are known for their complexation properties towards various cations. In this work, the complexation process between 1,3-bis(diphenylphosphoryl)-2-oxapropane (L) and lanthanide ions was studied. Namely, the stability constants of lanthanide complexes with L in acetonitrile were estimated by the method of spectrophotometric titration. It was found that the stability constants of Ln3+ complexes with L increase in the lanthanide series, which is consistent with the extraction and ion-selective properties of L. The extraction ability of L and this ligand in the presence of ionic liquids (ILs) such as methyltrioctylammonium nitrate (MTOAN) and bis[(trifluoromethyl)sulfonyl]imide 1-butyl-3-methylimidazolium (C4mimTf2N) was studied. It was found that in the presence of ILs, L extracts the elements of the yttrium subgroup of lanthanides much better than those of the cerium subgroup: SFLu/Ce(L–MTOAN) = 2.29; SFLu/Ce(L–C4mimTf2N) = 110.38. The use of the L–C4mimTf2N mixture in the processes of lanthanide separation into subgroups is much more efficient than the use of L without the addition of ILs or the use of the L–MTOAN mixture. The ion-selective properties of L towards Ln3+ ions were studied. Podand L exhibits potentiometric selectivity to Lu3+ ions. [ABSTRACT FROM AUTHOR]

The long‐term stability of Ni‐based catalysts, employed in the anode of anion exchange membrane water electrolyzers (AEMWE), has been a persisting concern. In this work, through a simple and powerful electrochemical anodization process, vertically aligned β‐NiOOH atomic sheets (vertical‐β‐NiOOH) grown on Fe‐doped Ni nanoplates (FeNi nanoplates) as a solution are offered. This innovative electrocatalyst demonstrates sustained stability of constant current density for over 120 d during the oxygen evolution reaction.The zero‐gap AEMWE cell harnessing the anodized FeNi nanoplates achieves a remarkable current density of 2.26 A cm−2 at 1.80 V with an energetic efficiency of 85.1%. It is anticipated that the electrochemically produced highly active, stable Ni‐based nanostructures demonstrate the potential in pushing the boundaries of AEMWE technology. [ABSTRACT FROM AUTHOR]

Ferroelastic textures called star patterns are transformable into grilles whose rigid bars replace domain boundaries and are connected with hinges at their junctions. The grilles show several levels of self‐similarity. Exact formulae for the scaling factors as functions of the shape and number N of the arms are provided. The minimal dynamic model of such systems involves force constants at only one level (generation) of self‐similarity. The minimal set of force constants ensures stability of the stars with N = 2 and N = 3. At N = 4 the minimal model exhibits exactly one mode of zero frequency. The reaction of the four‐arm star to a tensile stress applied at the level of the force constants depends on the self‐similarity scaling factor and on the separation between the applied stress and the generation where the observation is made. In some regions of these parameters the reaction is analogous to auxetics but it also shows negative tensile characteristics, that is, a shrinking in the direction of the stress axis. With increasing distance from the external perturbation toward outer generations of self‐similarity the system shows a surprisingly fast restoration of the symmetry broken by the stress. [ABSTRACT FROM AUTHOR]

Fast and sensitive quantification of drugs as emerging pollutants in water bodies is a pressing need in contemporary society, to prevent serious environmental concerns that could negatively impact on human health. This explains the surge of interest in this field, and the need to identify highly selective sensing systems. Addressing this issue, in this work we synthesized two D‐glucamine functionalized fluorophores bearing self‐assembling cores, as 1,8‐naphthalimide and naphthalene diimide. We studied their self‐assembly in water solution, and characterized the aggregated formed by determining their stability constant, their morphology and size by scanning electron microscopy, resonance light scattering and dynamic light scattering, as well their solid‐state emission ability. Then, we studied their sensing ability, in water, towards pharmaceutically active compounds such as ciprofloxacin, nalidixic acid, carbamazepine and diclofenac sodium salt, by fluorescence investigation. Data collected show that the self‐assembling ability is significantly affected by the fluorophore structure, which in turn also determines sensing ability. In particular, the naphtalene diimide‐based probe was the most sensitive, with LOD as low as 0.01 μM in the presence of nalidixic acid, which is in line and competitive with more complex sensing systems, recently reported in the literature. [ABSTRACT FROM AUTHOR]

The proton transfer (PT) complexation reaction between 3,4-diaminopyridine (3,4-DAP), an important drug, and 2,6-dichloro-4-nitrphenole (DCNP) was investigated experimentally and theoretically. The experimental results indicated a chemical reaction occurred because of a hydrogen bonding, followed by proton transfer from the DCNP to the 3,4-DAP in different polar media. The Benesi–Hildebrand equation was used to estimate the formation constant (Kf), molar absorptivity (εPT), and other physical parameters. The formed PT complex was characterized using FTIR, 1H, and 13C NMR spectra. In addition, the nanocrystalline structure, particle sizes, and surface morphology of the complex were investigated by XRD and SEM-EDX. The structure of the 1:1 PT complex was calculated theoretically in the gas phase and the presence of solvent effects. Using TD-DFT calculations, the band observed at 406 nm (Calc. 379.5 nm) and 275 nm (Calc. 272.3 nm) could be assigned to the HOMO→LUMO transition (99%), and HOMO→L+3 transition (87%), respectively. The DNA binding ability of the PT complex was investigated, revealing an intercalative binding mechanism with a binding constant Kb of 4.6 × 104 M−1. Based on the results of the Ct-DNA binding study, the binding free energy of the PT complex with the receptor of human DNA (PDB ID:1BNA) is found to be −7.2 kcal/mol. The cytotoxic effects of the PT complex were evaluated on selected cancer cell lines, demonstrating significant antitumor activity against A-549 and MCF-7 cancer cell lines. [ABSTRACT FROM AUTHOR]

This investigation aims to develop an angular stiffness sensor intended for measuring dental implant stability in bone. The sensor hardware included a tiny eccentric motor and an accelerometer to measure a flex constant of an implant with its abutment. The sensor software included a mechanics-based model to convert the flex constant to angular stiffness at the implant/abutment junction to indicate the stability. The sensor's accuracy and effectiveness are demonstrated through use of Sawbones slab models that mimic a mandibular premolar section. The models include a Branemark Mk III implant inserted into Sawbones slabs of 5 different densities with a locator abutment. An incremental insertion torque was first recorded while the implant was placed in the Sawbones models. Then benchtop experiments were conducted to measure resonance frequencies and angular stiffness. Results indicated that angular stiffness increased with Sawbones density, showing high correlation with the measured resonance frequency ( R = 0.977 ) and the incremental insertion torque ( R = 0.959 ). Finally, accuracy of the angular stiffness sensor is calibrated in light of the resonance frequency. Angular stiffness scores 99% and 95% accuracy for Sawbones models mimicking medium cancellous bones with and without a cortical layer, respectively. [ABSTRACT FROM AUTHOR]

We propose a notion of stability for constant k$k$‐mean curvature hypersurfaces in a general Riemannian manifold and we give some applications. When the ambient manifold is a Space Form, our notion coincides with the known one, given by means of the variational problem. [ABSTRACT FROM AUTHOR]

The presence of an excessive amount of iodine, especially radioactive iodine, is dangerous to the environment. Amine solutions are the most common and technically mature class of chemical sorption used for the capture of the pollutants. The iodine vapor diffusion and release capabilities of the aromatic amine solutions have been investigated. The iodine diffusion and release experiments were examined by UV-visible spectroscopy. Many electronic spectrophotometric studies have been reported in the coordination chemistry field on complexes. Generally, these complexes were obtained by using different electron donors with various organic or metallic electron acceptors in polar and non-polar solvents. The absorption spectra of the donor, acceptors, and the resulted complexes were carried out in methanol in the region of 200–600 nm. The correlation between the spectral characteristics of molecular complexes of iodine with various aromatic amines and the ionization potentials of the donor molecules is discussed. The concentrations of the diffused iodine and the formed complex were calculated using mathematical models and calibration curves. The values of the formation constant (kAD), molar extinction coefficient (εAD), and absorption band energy of complexes were estimated. The ionization potential of the donor ID was calculated from the complex band energies. The kinetic of the above association and reverse reactions was studied, and some kinetic parameters have been estimated. [ABSTRACT FROM AUTHOR]

Novel compounds with pharmacological activity were synthesized from Pd(II), Fe(III), Cr(III), Ni(II), and Cu(II) ions with 1‐cyclopropyl‐6‐fluoro‐4‐(2‐hydroxy‐phenylimino)‐7‐piperazin‐1‐yl‐1,4‐dihydro‐quinoline‐3‐carboxylic acid (CFAP). The ligand's NH and OH groups allowed it to interact with the metals as a neutral tridentate. The investigated novel compounds were described using 1H and 13C NMR spectra, FT‐IR spectrums, TGA and UV–Vis (conductance of molecules), and CHN‐analysis. Additionally, the pH profile of the CFAP complexes indicated great stability, and the complexes' stability constant was discovered in the solution. To extract important properties for CFAP and its complexes, computational research was used, CFAPCu, CFAPCr, CFAPNi, and CFAPFe have octahedral geometry, while CFAPPd has square planar geometry. To investigate the molecular geometry, density functional theory calculations (DFT) were carried out. The molar ratio and continuous fluctuation data confirmed that the (M:L) ratio was (1:1). In vitro tests were conducted to evaluate Schiff base's antimicrobial action ligand and its metal chelates against fungal and bacterial infections. The findings showed that the antimicrobial efficacy is as follows: When CFAPPd is compared to fluconazol and ofloxacin as reference medications, it is the highly inhibitor complex. The novel CFAP ligand and its complexes were investigated for In vitro carcinogenic potential against Hep‐G2, MCF‐7, and HCT‐116 cell lines. As compared to the medication vinblastine, the results once again demonstrated that CFAPPd is the most active agent. Moreover, the complexes demnstrated strong reactivity in capturing free radicals when their antioxidant activity was investigated. Viscosity, spectral investigations, and gel electrophoreses were used to identify the interaction between metal chelates and DNA. Every examined compound is shown to be an enthusiastic DNA binder by viscosity and spectrophotometric titration investigations. The heightened hydrophobic and electrostatic interactions between aromatic rings could be the cause of this. Ultimately, these compounds could be regarded as promising bioactive substances. [ABSTRACT FROM AUTHOR]

Novel compounds with pharmacological activity were synthesized from Pd (II), Fe (III), Cr (III), Ni (II), and Cu (II) ions with 4‐{2‐(3‐carboxy‐1‐cyclopropyl‐6‐fluoro‐7‐piperazin‐1‐yl‐2,3‐dihydro‐1H‐quinolin‐4‐ylideneamino)‐phenylimino}‐1‐cyclopropyl‐6‐fluoro‐7‐piperazin‐1‐yl‐1,4‐dihydro‐quinoline‐3‐carboxylic acid (CFPD). The newly synthesized compounds have been investigated by 1H‐ and 13C‐NMR spectra, Fourier transform infrared spectra, CHN analyses, ultraviolet‐visible spectra, mass spectra, molar conductivity, and magnetic moment measurements. In addition, the pH profile of the CFPD complexes showed remarkable stability, and their stability constant was identified in solution. To find out essential characteristics for CFPD and its complexes and to investigate the molecular geometry, computational analysis occurred. Through its nitrogen and OH of carboxylate groups, the ligand interacted with the metal ions to form CFPDPd complex with a square planar geometry and CFPDCu, CFPDCr, CFPDNi, and CFPDFe complexes with octahedral geometry. The M:L ratio of 1:1 was demonstrated by the molar ratio and sequence variation techniques' outcomes. The effect of the investigated CFPD imine ligand on bacterial community and its metal chelate was examined within vitro using a range of fungal and viral pathogens The findings showed that the effectiveness of antimicrobial went with the directive: CFPDPd complex when compared to the highly suppressor complex, fluconazol and ofloxacin as model medication. The novel ligand's and its complexes' in vitro cytotoxic potential against the Hep‐G2, MCF‐7, and HCT‐116 cell lines was also studied. The findings once more indicated that, when compared to vinblastine medication, the CFPDPd chelate is the most active agent. In addition, the complexes showed high reactivity in catching free radicals when their antioxidant activity was examined. By the application of viscosity, spectrum analysis, and gel electrophoreses, the interaction among metal chelates and DNA was determined. Studies on viscosity and spectrophotometric titration showed that every substance in test is a strong DNA binder. Increased hydrophobic and electrostatic interactions between aromatic rings could be the cause of this. In conclusion, these complexes have the potential to be effective bioactive agents. [ABSTRACT FROM AUTHOR]

The paper introduces the VANET Mobility Regression Forecasting Network (VMRF-Net), a new model for effectively predicting vehicular mobility trends in VANETs (Vehicular adhoc Networks). VMRF-Net uses LSTM (Long Short Term Memory) layers with a 20% dropout rate to avoid overfitting and the 'adam' optimization method to improve learning efficiency. The suggested model produces remarkable results, including a 100% packet delivery ratio at lower node densities (20 and 40 nodes), as well as good performance at higher densities, with a minimum end-to-end delay of 0.29 seconds and a throughput of 1 at a node density of 20. Furthermore, the model shows a strong positive relationship between simulation duration and network sustainability, resulting in constant stability periods and longer operational lifetimes across different simulation lengths. These findings demonstrate the VMRF-Net's efficacy in improving VANET performance and resource utilization. [ABSTRACT FROM AUTHOR]

A significant challenge arises in powering distributed tiny sensors that gather high‐resolution soil data are crucial for advancing digital and geospatial technologies in the field. Traditional batteries and solar cells are unsuitable due to size mismatches. Microbial fuel cells lack stability in delivering constant power. Soil naturally contains redox‐active ions, such as Zn2+ and Mn2+, which can be harvested and utilized for electrochemical energy storage. To facilitate access to soluble ions, a microfluidic pump based on micro‐Swiss‐roll structures via micro‐origami is developed. Spontaneous capillary flow allows for efficient liquid extraction. The micro‐Swiss‐roll architecture shows significant improvements in redox reversibility and charge transfer within micrometer‐thick interlayer space. Notably, the interference of Zn0/2+ and Mn(II)/Mn(IV) reactions is suppressed. Consequently, the battery using a micro‐Swiss‐roll electrode shows high voltage and energy efficiency at high currents up to 10 µA, with cycling stability of 300 times. A twin‐micro‐Swiss‐roll architecture of 0.385 ± 0.006 mm2 is used for energy storage in wet soil, yielding over 40 times more energy as compared to soil‐microbial fuel cells. A conceptual demonstration of an integrated irrigation water sensor and micro‐Swiss‐roll battery highlights the potential of microbattery development in addressing the critical challenge of powering tiny sensors in the soil. [ABSTRACT FROM AUTHOR]

This study investigates the recognition of halide anions by N,N’-bis(4-nitrophenyl)urea using computational methods in both gas-phase and solution. It examines interaction, stabilization, and deformation energies, revealing a gas-phase selectivity trend of [L⋯F]−>[L⋯Cl]−>[L⋯Br]−>[L⋯I]−. NBO, QTAIM, and EDA-NOCV analyses highlight N-H∙∙∙X hydrogen bonds, with electrostatic forces contributing around 60% to the total interaction. Despite unfavorable solvation energy changes, the intrinsic affinity remains the main factor for selectivity, which aligns with experimental data. The strong correlation between theoretical and experimental formation constants supports the reliability of the computational findings. [ABSTRACT FROM AUTHOR]

It is widely accepted that solid oxide fuel cells (SOFCs) have the potential to be the most efficient and cost-effective system for the direct conversion of various fuels into electricity with low environmental pollution and high efficiency. Herein, we demonstrate a novel Fe-based high-entropy perovskite oxide as a cathode material for intermediate-temperature solid oxide fuel cells (IT-SOFCs). The high-entropy perovskite La 0.2 Pr 0.2 Sm 0.2 Nd 0.2 Sr 0.2 FeO 3-δ (HE-LSF), composed of La, Pr, Nd, Sm, and Sr is prepared by incorporating five components into the A-site of La 0.8 Sr 0.2 FeO 3-δ (LSF). Doping of Pr, Nd, Sm, and Sr into the A-site significantly enhances the redox stability of LSF and restrains the surface Sr-segregation in both oxidizing and reducing conditions. The electrode polarization resistance of the anode-supported single cell with HE-LSF cathode is significantly low at intermediate temperature. Meanwhile, at 800 °C, the power density is 1029.2 mW/cm2, and the polarization resistance (Rp) is 0.101 Ω cm2, while at 700 °C, the power density is 581.52 mW/cm2 with an Rp of 0.21 Ω cm2 in humidified H 2. Further, the HE-LSF cathode presents good and long-term stability at a constant voltage of 0.7 V for 100 h at 700 °C. The excellent electrochemical performance and stability results exhibit that Fe-based high-entropy perovskite oxide is a new promising candidate and cathode material for SOFCs at intermediate temperatures. [Display omitted] • Five components are incorporated in the A-site of LSF forming high entropy oxide. • Fe-based high entropy perovskite oxides are potential cathode materials for SOFCs. • HE-LSF-based single cell presents good stability under the operation condition. • High-entropy perovskite cathodes can suppress the Sr segregation. [ABSTRACT FROM AUTHOR]

The strengths of H-bonding interactions in networks are affected by cooperativity between the interacting sites. Compounds with an intramolecular H-bond between a sulfonamide NH group and pyridine nitrogen were used to measure the magnitude of cooperative effects on intermolecular H-bonding interactions with the sulfonamide oxygen. X-ray crystallography and 1H NMR experiments confirm the presence of the intramolecular H-bond and show that it is maintained in the 1 : 1 complex formed with perfluoro-tert-butanol (PFTB) in n-octane solution. Association constants for formation of 1 : 1 complexes with PFTB were determined using UV/Vis absorption titrations for a series of compounds equipped with different pyridine groups. Substituents on the pyridine were used to tune the strength of the intramolecular H-bond and investigate the effects on the strength of the intermolecular H-bond. Electron-donating groups on the pyridine that increase the strength of the intramolecular H-bond were found to increase in the strength of the intermolecular interaction with PFTB. The results were used to determine the H-bond acceptor parameters, β, for the sulfonamide oxygen group, and the values show a linear relationship with the value of β for the pyridine nitrogen. The slope of this relationship corresponds to the cooperativity parameter, κ, which is +0.16. The positive cooperativity observed in H-bonded sulfonamides is comparable to the value measured previously for the amide group (κ = +0.20). [ABSTRACT FROM AUTHOR]

Complex formation of vanadium(V) with 4-(2',3',4'-trihydroxyphenyl)-3-nitro-5-sulfoazobenzene (R) in the presence of cationic surfactants (CS), cetylpyridinium chloride (CPCl), cetylpyridinium bromide (CPBr), and cetyltrimethylammonium bromide (CTMABr), is studied. Vanadium(V) and R form a colored complex at a component ratio of 1 : 2 and pH of 5.0–5.5. The absorbance maximum of the complex is at 449 nm, while the reagent under these conditions absorbs light at 395 nm. In the presence of cationic surfactants, mixed-ligand complexes with a component ratio of V(V) : R : CS = 1 : 2 : 2 are formed, which results in a bathochromic shift of the absorbance maximum. Additionally, the pH value for the maximum complex formation shifts to a more acidic medium compared to the homoligand V(V)–R complex. The absorbance of the V(V) : R : CPCl, V(V): R : CPBr, and V(V) : R : CTMABr complexes is maximal at 457, 461, and 466 nm, respectively. The yield of these complexes is the highest at pH of 3.5–4.0 for VV(V) : R : CPCl and V(V): R : CPBr, and at a pH of 2.5–3.0 for V(V) : R : CTMABr. The formation of both homoligand and mixed-ligand vanadium(V) complexes depends on the reaction time, temperature, and concentrations of the reacting components. The determined stability constants indicate the high stability of the resulting mixed-ligand complexes. The specific conductivity of the complexes under the optimal conditions of complex formation was determined using conductometric titration. Calibration curves for the determination of vanadium(V) as homoligand and mixed-ligand complexes are linear. The effect of foreign ions and masking agents on the determination of V(V) as homoligand and mixed-ligand complexes was analyzed; it was shown that the presence of cationic surfactants significantly increases the selectivity of the reaction. An analysis of water samples from Lake Khanbulan, Lankaran District, Azerbaijan Republic using the developed procedure showed the presence of small amounts of vanadium(V). [ABSTRACT FROM AUTHOR]

The rare earth elements (REEs) are critical resources for many clean energy technologies, but are difficult to obtain in their elementally pure forms because of their nearly identical chemical properties. Here, an analogue of macropa, G‐macropa, was synthesized and employed for an aqueous precipitation‐based separation of Nd3+ and Dy3+. G‐macropa maintains the same thermodynamic preference for the large REEs as macropa, but shows smaller thermodynamic stability constants. Molecular dynamics studies demonstrate that the binding affinity differences of these chelators for Nd3+ and Dy3+ is a consequence of the presence or absence of an inner‐sphere water molecule, which alters the donor strength of the macrocyclic ethers. Leveraging the small REE affinity of G‐macropa, we demonstrate that within aqueous solutions of Nd3+, Dy3+, and G‐macropa, the addition of HCO3− selectively precipitates Dy2(CO3)3, leaving the Nd3+−G‐macropa complex in solution. With this method, remarkably high separation factors of 841 and 741 are achieved for 50 : 50 and 75 : 25 mixtures. Further studies involving Nd3+:Dy3+ ratios of 95 : 5 in authentic magnet waste also afford an efficient separation as well. Lastly, G‐macropa is recovered via crystallization with HCl and used for subsequent extractions, demonstrating its good recyclability. [ABSTRACT FROM AUTHOR]

A model two-dimensional acoustic waveguide with lateral impedance boundary conditions (and outgoing boundary conditions at the waveguide outlet) is considered. The governing operator is proved to be bounded below with a stability constant inversely proportional to the length of the waveguide. The presence of impedance boundary conditions leads to a non self-adjoint operator which considerably complicates the analysis. The goal of this paper is to elucidate these complications and tools that are applicable, as simply as possible. This work is a continuation of prior waveguide studies (where self-adjoint operators arose) by J. M. Melenk et al. (2023), and L. Demkowicz et al. (2024). [ABSTRACT FROM AUTHOR]

Sucrose constitutes a non-toxic, biodegradable, low-cost and readily available natural product. To expand its utility, we developed total synthesis for a ligand based on a sucrose scaffold for potential use as a metal chelation agent. The designed target (compound 2) has a metal-chelating functionality at both the C-6 and C-6' positions, which can provide a first coordination sphere of eight valencies. The designed total synthesis was highly efficient. To demonstrate the utility of the ligand, we studied its complexation with Gd(III). Using potentiometric titration and high-resolution mass spectrometry, we confirmed the formation of a 1:1 complex with Gd(III), which has a respectable formation constant of ~1013.4. Further NMR relaxivity studies show that the Gd(III) complex has a relaxivity (r1) of 7.6958 mmol−1 s−1. [ABSTRACT FROM AUTHOR]

Research in the field of metallodrugs is continually increasing. However, it is often limited by the poor solubility in water of the metal complexes. To try to overcome this problem, the two new ligands bis-(sodium 3-methoxy-5-sulfonate-salicylaldehyde)thiocarbohydrazone (bis-TCH, Na2H4L1) and bis-(sodium 3-methoxy-5-sulfonate-salicylaldehyde)carbohydrazone (bis-CH, Na2H4L2) were synthesized and characterized, both achieving high solubility in water. The speciation of the ligands and their coordinating behaviour towards the biologically relevant Cu(II) and Zn(II) ions were studied spectroscopically and potentiometrically, determining the pKas of the ligands and the formation constants of the complex species. The monometallic and bimetallic Cu(II) and Zn(II) complexes were isolated, and the single-crystal X-ray structure of [Cu2(NaHL1)(H2O)7].3.5H2O was discussed. Finally, preliminary studies of the in vitro cytotoxic properties of the new compounds were started on normal (Hs27) and cancer (U937) cell lines. bis-TCH was able to induce a growth inhibition effect between 40% and 45% in both cell lines; bis-CH did not produce a reduction in cell viability in Hs27 cells but revealed mild antiproliferative activity after 72 h of treatment in U937 cancer cells (GI50 = 46.5 ± 4.94 μg/mL). Coordination of the Cu(II) ions increased the toxicity of the compounds, while, in contrast, Zn(II) complexes were not cytotoxic. [ABSTRACT FROM AUTHOR]

This paper considers a two‐species chemotaxis system with chemical signaling loop and Lotka–Volterra competition kinetics under the homogeneous Newman boundary condition in smooth bounded domains. The global existence and boundedness of solutions for the parabolic–elliptic/parabolic–parabolic system are established. In the strong competition case, the global stability of the semitrivial constant steady state is obtained under certain parameter conditions. Linear analyzes and numerical simulations demonstrate that chemical signaling loop can significantly impact population dynamics, and admit the coexistence in the exclusion competitive case, including nonconstant steady states, chaos, and spatially inhomogeneous time‐periodic types. [ABSTRACT FROM AUTHOR]

The list of standard abbreviations for JDS is available at adsa.org/jds-abbreviations-24. Nonstandard abbreviations are available in the Notes. Products of lipolysis released during digestion positively affect the metabolism of newborns. In contrast to the 3-layer biological membranes covering human milk (HM) fat, the lipid droplets in infant milk formula (IMF) are covered by a single membrane composed of casein and whey proteins. To reduce the differences in lipid structure between IMF and HM, studies have used milk fat globule membrane (MFGM) components such as milk polar lipids (MPL) to prepare emulsions mimicking HM fat globules However, few studies have elucidated the effect of membrane proteins (MemP) on lipid digestion in infants. In this study, 3 kinds of emulsions were prepared: one with MPL as the interface of lipid droplets (RE-1), one with membrane protein concentrate (MPC; RE-2) as the interface of lipid droplets, and one with both MPL and MPC (1:2) as the co-interface of lipid droplets (RE-3). The interfacial coverage of the emulsions was confirmed by measuring the contents of MPL and MPC at the lipid droplet interface, and by confocal laser scanning microscopy analysis. By controlling the homogenization intensity, the specific surface area of lipid droplets was controlled at the same level among the 3 emulsions. The stability constants of the emulsions varied, and RE-1 was the most stable. During simulated in vitro infant gastrointestinal digestion, the amount of free fatty acids (FFA) released from the lipid droplets was significantly higher from those with MPC at the interface (RE-2, RE-3) than from that with MPL at the interface (RE-1). The amount of FFA released at the end of intestinal digestion of RE-1, RE-2, and RE-3 was (mean ± SD; n = 3) 255.00 ± 3.54 µmol, 328.75 ± 5.30 µmol, 298.50 ± 9.19 µmol, respectively. Compared with the lipid droplets in RE-2, those with MPL at the interface (RE-1, RE-3) released more UFA during digestion. The emulsifying activity index was highest in RE-3 (MPL and MPC co-interface). The presence of MPL at the emulsion interface increased the release of UFA, and the presence of MPC increased the release of FFA. These results show that both MPL and MemP are indispensable in the construction of MFGM. Understanding their effects on digestion can provide new strategies for the development of infant foods. [ABSTRACT FROM AUTHOR]

In this paper, we analyze the discrete inf-sup condition and related error estimates for a modified Hilbert transformation as used in the space-time discretization of time-dependent partial differential equations. It turns out that the stability constant c S depends linearly on the finite element mesh size h. While the ratio c S / h decreases as 1 / T for T → ∞ , numerical results indicate a decay of c S / h ≃ ν − α for some α ∈ [ 1 4 , 1 3 ] in the polynomial degree ν of the finite element basis functions. However, in most cases, we can show optimal convergence. We present a series of numerical experiments which illustrate the theoretical findings. [ABSTRACT FROM AUTHOR]

The aim of this study was to systematically analyze the influence of potential and the Co(II)–Ru(III) molar ratio on the electrochemical behavior of the Co–Ru system during codeposition from acidic chloride electrolytes. The equilibrium speciation of the baths was investigated spectrophotometrically and compared with theoretical calculations based on the stability constants of Co(II) and Ru(III) complexes. The codeposition of the metals was characterized using electroanalytical methods, including cyclic voltammetry, chronoamperometry, and anodic stripping linear voltammetry. The alloys obtained at different potentials were analyzed for their elemental composition (EDS, mapping), phase composition (XRD), and surface morphology (SEM). The morphology and composition of the alloys were mainly dependent on the deposition potential, which controlled the cobalt incorporation. Ruthenium–rich alloys were produced at potentials of −0.6 V and −0.7 V (vs. SCE). In these conditions, cobalt anomalously codeposited due to the formation of the CoOH+ intermediate, triggered by the intense hydrogen evolution on the ruthenium sublayer. Bulk cobalt electrodeposition began at a potential of around −0.8 V, resulting in the formation of cobalt-rich alloys. The early stages of the electrodeposition were investigated using different nucleation models. A transition from 2D progressive nucleation to 3D instantaneous nucleation at around −0.8 V was identified as being caused by cobalt incorporation. This was well correlated with electroanalytical data, partial polarization curves of alloy deposition, elemental mapping analysis, and the structure of the deposits. [ABSTRACT FROM AUTHOR]

Submarine channels on the seafloor experience a range of turbidity current‐flood hydrographs. The characteristics of the flood hydrograph influence channel dimensions, the number of channel threads (i.e. braiding intensity) and the depositional properties of sandbars within the channels. However, the morphodynamic response of submarine braided channels to different hydrograph patterns is poorly understood. In this study, six geomorphic experiments are used to test how varied flood hydrographs affect the braiding intensity and sandbar geometry within submarine channels. Three experiments represent the control group with constant density‐current inflow, and three experiments use different time‐varying hydrograph patterns. The experiments show that, as the inflow‐to‐sediment discharge ratio increases, multiple small channels coalesce into a few main channels, causing a decrease in active braiding intensity defined by the channel threads with flow. When the flow returns to the initial low flow rate, active braiding intensity increases again. These observations show that the inflow‐to‐sediment discharge ratio determines the value of active braiding intensity. Additionally, active braiding intensity is directly proportional to dimensionless sediment‐stream power and dimensionless stream power, in agreement with previously established trends for both submarine and fluvial braided channels. In contrast to active braiding intensity changes, the measured sandbar aspect ratio and compactness ratio (i.e. ratio of planform area to perimeter) of submarine braided channels is insensitive to changes in the hydrograph. However, when inflows reach peak discharge, the higher transport capacity erodes pre‐existing deposits, forming noticeable erosional surfaces, and subsequently depositing thicker sandbars during that stage. These observations imply that sandbar planform morphology is largely insensitive to hydrograph, but hydrograph variability induces a greater variability in the resultant stratigraphic packages. The experimental results predict that field‐scale stratigraphy should be dominated by strata deposited during intervals of high flow, but that these strata will also exhibit reduced lateral continuity compared to formation scenarios with constant discharge. [ABSTRACT FROM AUTHOR]

ABSTRACT The synthesis and structural analysis of complexes derived from (E)‐N′‐(3,5‐di‐tert‐butyl‐2‐hydroxybenzylidene) isonicotino hydrazide (ITB ligand) were examined using multiple analytical techniques. These techniques included TGA, decomposition point determination, elemental analysis (CHN), spectroscopic (IR, NMR, mass spectrometry) analysis, magnetic susceptibility, conductivity, as well UV–Vis spectrum analysis, along with theoretical studies. Molar conductance values indicated that the Cd (II), Co (II), Cu (II), Ni (II), and Zn (II) complexes are non‐electrolytes in fresh DMSO solutions, with conductance values ranging from 8.5 to 14.35 Ω−1 cm2 mol−1. IR spectra suggested which the ligand coordinates through the metal ions in a tridentate fashion, utilizing the (N & O) donor sites from the (CN & CO & CO) groups in the hydroxybenzylidene moiety. Analytical data from solution complexation, job's method suggested a 1:1 (metal:ligand) molar ratio. The stability order of the complexes was determined as ITBCo > ITBCu > ITBNi > ITBZn > ITBCd, consistent with the stability constant (Kf) values. The pH profile indicated that the studied complexes exhibit stability upon a wide pH scale, typically between (pH = 4:10). Magnetic and electronic spectral analyses helped deduce the ligand coordination abilities and the geometric structures of the complexes. In vitro (antimicrobial & anticancer) performances of the studied complexes were tested versus various (microbial strains & cancer cell lines), revealing higher activity in the chelates assessed to the free (ITB) ligand. The antioxidant potential was also assessed using the DPPH assay. Finally, molecular docking was performed toward estimate the binding efficiency between various protein receptors and the compounds, with results aligning with the biological investigations. [ABSTRACT FROM AUTHOR]

The present study deals with the production of cellulase-free endoxylanase by Aspergillus niger ISL-9 using wheat bran as a solid substrate. Endoxylanase was produced under a solid-state fermentation. Various growth parameters were optimized for the improved production of the enzyme. The Substrate level of 15 g was optimized as it provided the fungus with balanced aeration and nutrition. Among the six moisture contents investigated, Moisture Content 5 (MC5) was optimized (g/l: malt extract, 10; (NH4)2HPO4, 2.5; urea, 1.0) and 10 mL of MC5 was found to give the highest production of endoxylanase. The pH and time of incubation were optimized to 6.2 and 48 h respectively. The Inoculum size of 2 mL (1.4 × 106 spores/mL) gave the maximum enzyme production. After optimization of these growth parameters, a significantly high endoxylanase activity of 21.87 U/g was achieved. Very negligible Carboxymethylcellulase (CMCase) activity was observed indicating the production of cellulase-free endoxylanase. The notable finding is that the endoxylanase activity was increased by 1.4-fold under optimized conditions (p ≤ 0.05). The overall comparison of kinetic parameters for enhanced production of endoxylanase by A. niger ISL-9 under Solid State Fermentation (SSF) was also studied. Different kinetic variables which included specific growth rate, product yield coefficients, volumetric rates and specific rates were observed at 48, 72 and 96 h incubation time and were compared for MC1 and MC5. Among the kinetic parameters, the most significant result was obtained with volumetric rate constant for product formation (Qp) that was found to be optimum (1.89 U/h) at 72 h incubation period and a high value of Qp i.e.1.68 U/h was also observed at 48 h incubation period. Thus, the study demonstrates a cost-effective and environmentally sustainable process for xylanase production and exhibits scope towards successful industrial applications. [ABSTRACT FROM AUTHOR]

This paper investigates the trends of three different species interacting in the same ecosystem. The study is conducted on the ecosystem which consists of a prey S1 and two predators S2 and S3 in such a way that S2 is a predator of S1 and S3 is a predator of both S1 and S2. In addition, S1 and S2 share the same food which is the main food for S1 and the alternative food for S2. A system of three simultaneous nonlinear partial differential equations is used to represent this situation. The local stability of all constant equilibrium points is discussed after showing their feasibility. In addition, a condition for which a coexisting constant equilibrium point is asymptotically globally stable is also investigated. The results showed that the system has eight constant equilibrium points. Five of them are unstable, while the three remaining are asymptotically locally stable under some conditions on the parameters that are involved in the model. [ABSTRACT FROM AUTHOR]

Indium-111 (111In) is a diagnostic radiometal that is important in nuclear medicine for single-photon emission computed tomography (SPECT). In order to apply this radiometal, it needs to be stably chelated and conjugated to a targeting vector that delivers it to diseased tissue. Identifying effective chelators that are capable of binding and retaining [111In]In3+ in vivo is an important research area. In this study, two 18-membered macrocyclic chelators, py-macrodipa and py2-macrodipa, were investigated for their ability to form stable coordination complexes with In3+ and to be effectively radiolabeled with [111In]In3+. The In3+ complexes of these two chelators were characterized by NMR spectroscopy, X-ray crystallography, and density functional theory calculations. These studies show that both py-macrodipa and py2-macrodipa form 8-coordinate In3+ complexes and attain an asymmetric conformation, consistent with prior studies on this ligand class with small rare earth metal ions. Spectrophotometric titrations were carried out to determine the thermodynamic stability constants (log KML) of [In(py-macrodipa)]+ and [In(py2- macrodipa)]+, which were found to be 18.96(6) and 19.53(5), respectively, where the values in parentheses are the errors of the last significant figures obtained from the standard deviation from three independent replicates. Radiolabeling studies showed that py-macrodipa and py2-macrodipa can quantitatively be radiolabeled with [111In]In3+ at 25 °C within 5 min, even at ligand concentrations as low as 1 μM. The in vitro stability of the radiolabeled complexes was investigated in human serum at 37 °C, revealing that ∼90% of [111In][In(py-macrodipa)]+ and [111In][In(py2-macrodipa)]+ remained intact after 7 days. The biodistribution of these radiolabeled complexes in mice was investigated, showing lower uptake in the kidneys, liver, and blood at the 24 h mark compared to [111In]InCl3. These results demonstrate the potential of py-macrodipa and py2-macrodipa as chelators for [111In]In3+, suggesting their value for SPECT radiopharmaceuticals. [ABSTRACT FROM AUTHOR]

Detection of the AlCl molecule in IRC+10216 has been reported in the literature. We here report calculations of reaction rate constants for formation of AlCl through radiative association of Al and Cl for a temperature interval of 1000 to 14000 K. Potential energy and permanent/transition dipole moment curves were taken from the literature. Quantum mechanical and semiclassical/classical methods were used to obtain the reaction cross-sections and thermal rate constants, accounting for shape resonances with Breit–Wigner theory. Both the A |$^1 \Pi \rightarrow$| X |$^1 \Sigma ^+$| transition and the X |$^1 \Sigma ^+\rightarrow$| X |$^1 \Sigma ^+$| transition have been treated, with results showing that the former dominates for the temperatures considered in this study. Our rate constants are a factor of two to three larger than previously calculated values, where the latter were obtained without considering resonances or the X |$^1 \Sigma ^+\rightarrow$| X |$^1 \Sigma ^+$| transition. Our new values do however not change the previous conclusion that radiative association can only contribute modestly to the formation of AlCl under the given conditions. [ABSTRACT FROM AUTHOR]

The interaction of Thorium(IV) with a group of non‐symmetric CF3‐diketones has been studied by means of electronic absorption spectroscopy in HCl aqueous solutions at I=0.5 M (NaCl) and T=298 K. Six heterocyclic dicarbonyl ligands (2‐thenoyl‐trifluoroacetone, 2‐furoyl‐trifluoroacetone, 2‐selenophen‐trifluoroacetone, 2‐tellurophen‐trifluoroacetone, phenyl‐trifluoroacetone, and 2‐naphthyl‐trifluoroacetone) demonstrate the chelation activity toward ThIV in the acidic pH range. Obtained values of the "true" stability constants lie in the range 6.2–6.8 logarithmic units, respectively. A significant (10–15 nm) bathochromic shift between the maximum absorption wavelength of lanthanide and actinide monocomplexes has been detected. Observed spectral shift increases with the atomic number of substituted chalcogen atoms in the heterocyclic ring of the corresponding ligand: 10 nm for furan, 11 nm for thiophen, 14 nm for selenophen, and 15 nm for tellurophene rings. The complexation with Thorium occurs in an acidic media, where studied ligands do not interact with transition and rare earth metals. Spectral and pH shifts make studied ligands useful reagents for the detection and analytical determination of Thorium in the mixture with other metals without prior separation. Quantum‐chemical simulations (DFT and TD‐DFT) demonstrate that the nine‐ and deco‐coordinated structures of ThoriumIV complexes reproduce experimental values within reasonable errors. [ABSTRACT FROM AUTHOR]

Polyphenols form nanofilms with transition metal ions by coordination‐driven assembly. The as‐formed metal‐polyphenol nanofilms can degrade in the presence of chelating ligands that exhibit high stability constant with the nanofilm‐forming metal ions. We have demonstrated the degradation of Fe(III)‐tannic acid nanofilms with hydroxyketone ligands, such as maltol, kojic acid, and deferiprone, which exhibit high availability and excellent cytocompatibility. The concentration screening experiments have been performed with different ligand concentrations ranging from 1 mM–25 mM. It is important to note that only deferiprone degrades Fe(III)‐TA nanofilms even at 1 mM, and it retains the degradation activity at pH 7.4. The characteristic degradation activity of hydroxyketone ligands to Fe(III)‐TA nanofilms may depend upon their pKa value and stability constant. The degradation studies herein are attractive for the development of biomedical applications utilizing metal‐polyphenol nanofilms as a sacrificial template. [ABSTRACT FROM AUTHOR]

In this work, we have studied the stability constants of ternary cobalt(II) complexes with the primary ligands: pyridine-2,3-dicarboxylic acid (H22,3-Dipic, H2L) and pyridine-3,4-dicarboxylic acid (H23,4-Dipic, H2L) and secondary ligands representing low molecular mass components of blood serum: lactic acid (HLac), oxalic acid (H2Ox), citric acid (H3Cit), and phosphoric acid (H3PO4). Potentiometric data were analyzed using the least squares computational program LETAGROP. Ionic strength and temperature were both kept constant using 1.0 mol dm−3 NaNO3 as ionic medium at 25 °C. Species distribution diagrams were generated to determine the speciation variations with respect to pH. [ABSTRACT FROM AUTHOR]

This work addresses stochastic integro-delay differential equations (SIDDEs) of second order with two constant delays. In the study, two new results including sufficient conditions on stochastic asymptotic stability and stochastic boundedness in probability of solutions of the given SIDDEs are proved. The proofs of new results are done by using a Lyapunov-Krasovskii functional (L-KF) as a basic tool. To demonstrate the validity of the obtained results, two examples are provided. According to a comparison with previous literature, the results of this study are new and also allow new contributions to the qualitative theory of SIDDES. [ABSTRACT FROM AUTHOR]

The formation of mononuclear complexes and a heterovalent compound in the FeII—FeIII—l-Ala—H2O system was observed when using the Clark—Nikolsky oxidation potential at a temperature of 298.15 K and an ionic strength of the (Na(H)ClO4) solution equal to 0.75 mol L−1. The method of successive approximations (iteration) of the Yusupov oxidation function was used to calculate the stability and the model parameters of the mononuclear coordination compounds [FeHL(H2O)5]3+, [Fe(HL)2(H2O)4]3+, [Fe2(HL)2(OH)4(H2O)6]2+, [FeIIIFeII(HL)2(OH)4(H2O)6]+, [FeHL(H2O)5]2+, [Fe(HL)(OH)(H2O)4]+, and [Fe(HL)(OH)2(H2O)3]0 (L is an alanine ligand), the formation constants of these complexes, to determine the regions where they are dominant and their maximum degrees of accumulation, as well as to plot the diagrams of their distribution as a function of pH. It was determined that the heterovalent complex is the most stable and dominates up to pH 9.5. [ABSTRACT FROM AUTHOR]

The characterization of bioactive components in the methanolic and isopropyl alcoholic plant extracts of Spermadictyon suaveolens Roxb. (Rubiaceae) was undertaken with the help of GC-MS technique, followed by the study of free-radical scavenging capabilities of the plant hydroalcoholic extracts using DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) test technique with ascorbic acid as the standard. There's a constant formation of free radicals in the human body tissues originating due to the oxidation of specific chemical components, whereas the antioxidant molecules prevent or inhibit this free radical formation that may lead to lifelong or terminal diseases. The comparison of the antioxidant capacity of the plant extracts with that of the standard revealed that the leaf extracts showed maximum inhibition of DPPH, or radical scavenging activity. The EC50 values of ascorbic acid, leaves, stem, and root were found to be 18.62 μg/mL, 44.668 μg/mL, 89.125 μg/mL, and 97.723 μg/mL, respectively. The different peaks in the GC-MS analysis spectrum determined 24, 19, and 26 phytochemicals in leaves, stems, and roots, respectively. Out of all the phytoconstituents found, the major ones were n-Hexadecanoic acid or palmitic acid, squalene, 1.4-tert-Butylcalix[4]arene, and 1.3,5-Dihydroxy-6-methyl-2,3-dihydro-4H-pyran-4-one in leaves. 11-Bromoundecanoic acid, Ethylhexanol, Tetratetracontane, 2-Decanol, Propanoate in Stem, and n-Hexadecanoic acid 9,12-Octadecadienoic acid (Z,Z), 4,6-Bis(4-fluoro-3-(trifluoromethyl) phenoxy)-2-pyrimidinol, squalene in roots. Thus, the different bioactive constituents found to be present in the plant under study prove that the plant has the capacity to exhibit good antioxidant and other pharmacological properties. [ABSTRACT FROM AUTHOR]

The distribution equilibria of Am(III) and Cm(III) between the organic phase of bis(2,4,4-trimethylpentyl)dithiophosphonic acid (purified Cyanex301, HA) in xylene and aqueous solutions containing varying concentrations of formic acid or glycolic acid have been investigated aiming at the separation of the two actinides from each other after the groups separation of Am(III)/Cm(III) from Ln(III) ions. The apparent extraction constants for Am(III) and Cm(III) in the Cyanex301-xylene system are determined to be −8.84 and −9.37, respectively, at 0.01 M ionic strength. The specific ion interaction method (SIT) is used to obtain the stability constants of Am(III) and Cm(III) with nitrate and glycolate for calculating the speciation of the ions in extraction at 25°C and I = 0.01 M. The separation of Cm(III) from Am(III) loaded in 0.5 M HA in xylene can be considerably improved by emplying 0.01 to 0.05 M formic acid or glycolic acid as selective stripping reagents favoring complexation with Cm(III). Specifically, with 0.01 M formic acid or glycolic acid in the aqueous phase, the separation factor (SF) for Am(III) over Cm(III) is improved from 3.61 to 5.87 and 5.26, respectively. Hence, both separations of An(III) from Ln(III) and then Am(III) from Cm(III) are achieved by a selective extraction process at first and then a selective stripping process in one simple efficient system using purified Cyanex301 as extractant in organic phase and carboxylic acids as stripping chelates in aqueous. [ABSTRACT FROM AUTHOR]

Olanzapine (OLZ) is an antipsychotic drug with low aqueous solubility. Cyclodextrin (CD) complexation is a potential approach employed to improve the solubility of poorly water-soluble drugs belonging to BCS classes II and IV. The solubility of olanzapine was improved using βCD, HPβCD and methyl βCD which was reported in earlier works. In the current study, a combination of βCD and HPβCD in 1:1 molar ratio was used in the preparation of complexes along with βCD and HPβCD. Methods such as slugging, hydration and granulation which are slight modifications of conventional methods like physical mixing and slugging were used. AL type curves were obtained in phase solubility studies specifying a linear increase in the solubility of drug with increase in concentration of cyclodextrin. The values of slopes calculated for AL type plots are less than one which suggests that OLZ:CD complexes are formed in 1:1 molar ratio. The stability constants obtained were 188.98 M -1, 140.63 M -1 and 157.48 M -1 with βCD, HPβCD and βCD+HPβCD and these values indicate that stable OLZ : CD complexes are formed. The drug : cyclodextrin binary complexes demonstrated a 2.27 to 3.67 - fold increment in aqueous solubility when compared to pure drug. The percentage of drug released in 60 minutes was 46 (pure drug), 65 - 89 (OLZ-βCD complexes), 59 - 80 (OLZ-HPβCD complexes) and 61 - 84 (OLZ-βCD+HPβCD complexes). Results of DSC, XRD and SEM indicated partial inclusion complexation. The complexes prepared by hydration method showed higher solubility when compared to other methods. In hydration method, the complexes were prepared using water which does not cause any harm to individual and environment. [ABSTRACT FROM AUTHOR]

Binary systems of lanthanide ions (La, Nd, Gd, Ho, Tb, and Lu) with L-malic acid in molar ratios of 1:1 and 1:2 were studied. This study was carried out in aqueous solutions, and the composition of the formed complexes was confirmed using computer data analysis. The overall stability constants of the complexes and the equilibrium constants of the reaction were determined. The effect of ligand concentration on the composition of the internal coordination sphere of the central atom was observed. Changes in the coordination sphere of lanthanide ions were confirmed by spectroscopic measurements. [ABSTRACT FROM AUTHOR]

Purpose: The meniscal vascularization remains poorly documented, particularly its origin. The aim of this cadaveric study was to describe the origin of the arterial vascularization of the menisci. Methods: This is an anatomical study on human specimens. Twenty knees were used. The average age of the subjects was 82.7 years old (56–97). Ten knees were injected with latex-neoprene and ten knees were injected with colored gelatin mixed with India ink. The same protocol for dissection was used in all cases. Results: The meniscal vascularization is provided by the genicular arteries of the knee originating from the popliteal artery. The superior medial, superior lateral, inferior medial, inferior lateral, and middle genicular arteries had constant pathways. A second middle genicular artery was found in 55% of cases. The inferior lateral genicular artery ran alongside the meniscal's periphery. The inferior medial genicular artery followed the proximal tibial metaphysis. In all dissections, a previously undocumented small artery originated from under the middle genicular arteries. This artery remained extracapsular and followed the medial meniscal periphery. This artery has been named the "medial capsulo-meniscal artery". The genicular arteries formed an extensive peri-articular anastomotic vascularization for the menisci and thus referred to the "peri-meniscal arterial archs". The lateral peri-meniscal arch was predominantly supplied by the inferior lateral genicular artery, while the medial peri-meniscal arch was mainly supplied by the medial capsulo-meniscal artery. Conclusion: The peri-meniscal arterial archs are a vascular complex formed by the genicular arteries of the knee and an artery not previously described: the "capsulo-meniscal artery". These archs have a constant presence but their formation and distribution is different between the medial and lateral menisci. [ABSTRACT FROM AUTHOR]

In this paper, we study Chaplain–Lolas model in three dimensional bounded domain, which describes the invasion and diffusion process of solid tumors during the vascular growth stage. Although the model has received extensive attention since it was proposed, the existence of solutions in three-dimensional space is still missing, and only a global small solution is established by Pang and Wang (Math Models Methods Appl Sci 28(11):2211–2235, 2018) with sufficiently small proliferation coefficient. As for long time behavior, there are only corresponding stability result of constant steady-state for the case without ECM remodelling (Hillen et al. in Math Models Methods Appl Sci 25(1):165–198, 2013; Tao and Winkler in SIAM J Math Anal 47:4229–4250, 2016). If the remodeling effect of ECM is considered, the relevant research is still blank. In this paper, we first pay our attention to the study of existence of global strong solution and long time behavior. We prove that when the ratio of cell proliferation coefficient to chemotactic intensity μ χ 2 is large, there exists a unique global strong solution around the equilibrium state (1, 1, 0), and the global strong solution converges exponentially to the constant equilibrium point. In fact, such a largeness restriction on μ χ 2 is actually necessary to some extent, since that the constant equilibrium point (1, 1, 0) is actually linearly unstable when such a condition is not satisfied. Subsequently, we turn our attention to the study of dynamic behavior of solutions. We introduce a time periodic external force to this system, and prove that the solution will gradually show the same periodic behavior under the action of periodic external force, and become a time periodic solution. At last, we analysis the stability and instability of equilibrium points, and discuss the influence of spatial diffusion, chemotaxis and haptotaxis effect on the stability of solutions. In particular, we find that only chemotaxis can change the stability of the solution and make the originally stable equilibrium (1, 1, 0) unstable, while the haptotactic term has no effect on the stability. [ABSTRACT FROM AUTHOR]

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The excessive use of biocides has considerable environmental and economic impacts; this is why new technologies have been sought to decrease the concentration levels applied in an effort to reduce the use of these substances. Microencapsulation using cyclodextrins has been widely used in the food and pharmaceutical industries as a way of reducing the concentrations of the active substance necessary to achieve a biological effect and/or eliminate its irritating or toxicological effects. In this study, the inclusion complexation behavior and binding ability of benzothiazolinone (BIT) with different β-cyclodextrins (β-CD, HP-β-CD, and Me-β-CD) was investigated. The intermolecular interactions were examined through UV and FTIR spectroscopy, DSC, 1D 1H NMR, and 2D ROESY. The highest stability constant was observed for the BIT/Me-β-CD inclusion complex (299.5 ± 2.9 M−1). Antibacterial activity was investigated against Staphylococcus aureus and Escherichia coli, and the results revealed that the BIT/Me-β-CD inclusion complex displays a higher antibacterial activity than BIT. The acute toxicity of the biocide and inclusion complex was also examined using the photobacterium Aliivibrio fischeri. Although BIT exhibited higher toxicity than the inclusion complex, further investigation is needed due to the quorum quenching effect of β-CDs. The data found suggest that BIT microencapsulation can increase its aqueous solubility and can be used as an effective tool to improve its chemical, biological, and ecotoxicological properties. [ABSTRACT FROM AUTHOR]

Previous studies on the physical properties of alloy materials often focus solely on analyzing the impact of individual alloying element content, overlooking the underlying mechanism behind the synergistic action of multiple alloying elements. Therefore, in this study, we propose a combination of high-throughput computation and numerical analysis to conduct single-element (SE) analysis and multi-element (ME) analysis on the internal relationships between alloying element content and physical properties for the multi-component Nix1Crx2Cox3Al15Ti10 alloys, aiming to elucidate the competition mechanism among the Ni, Cr, and Co elements. The analysis of SE reveals how the physical properties of alloys are affected by the content of each individual alloying element, and the ME analysis further unveils the underlying competitive relationships among multiple alloying elements. The order of competitive intensity for the formation of lattice constant is Cr > Co > Ni, whereas for the formation of elastic constants and elastic moduli it is Ni > Co > Cr. At the same time, there are contradictory conclusions, such as the SE analysis showing that the Ni content is positively correlated with elastic constant C 11 , while the ME analysis demonstrates that the Ni element produces a negative competitive direction. This outcome arises from the omission of considering the combined impacts of various alloying elements in SE analysis. Therefore, the ME analysis can compensate for the limitations of SE analysis, and the integration of these two analytical methods is more conducive to elucidating the competition mechanism among various alloying elements in shaping the physical properties of alloys, which provides a promising avenue for theoretical research. [ABSTRACT FROM AUTHOR]

The stability of a trait refers to the extent to which its expression in a given genotype varies across environments. The more stable a trait, the less variable its expression. Grain yield stability is a central consideration in corn production to ensure that hybrids perform consistently across environments and is frequently quantified given its importance. Little attention has been paid to the stability of corn yield components, kernel number per m² (KN), and kernel weight (KW). Our hypothesis is that while previous research suggests that yield stability of commercial corn hybrids is generally consistent, the stabilities of KN and KW may exhibit significant differences, even when overall yield stability remains constant. This study evaluated the yield and yield component stabilities of 23 commercial corn hybrids conducted on-farm at five location-years in Ontario, Canada, using Finlay–Wilkinson regression. Most (61%) hybrids exhibited average yield stability with β1-values close to 1.0. But seven hybrids displaying average yield stability had KN and/or KW stabilities significantly different than average. While in absolute terms, KW was always more stable than KN across environments, the data indicate that hybrids have different mechanisms to achieve stable yields in terms of relative yield component adjustments. Overall, 14 hybrids had yield component β1-values significantly more or less stable than average. The instances where yield component β1-values differed significantly from 1.0 were almost equally divided between KN and KW. These findings support the potential for hybrid-specific corn management, that is, tailoring management practices to take advantage of hybrid variation in yield component stabilities. [ABSTRACT FROM AUTHOR]

The formation of mononuclear complexes and a heterovalent compound in the FeII—FeIII—l-Ala—H2O system was observed when using the Clark—Nikolsky oxidation potential at a temperature of 298.15 K and an ionic strength of the (Na(H)ClO4) solution equal to 0.75 mol L−1. The method of successive approximations (iteration) of the Yusupov oxidation function was used to calculate the stability and the model parameters of the mononuclear coordination compounds [FeHL(H2O)5]3+, [Fe(HL)2(H2O)4]3+, [Fe2(HL)2(OH)4(H2O)6]2+, [FeIIIFeII(HL)2(OH)4(H2O)6]+, [FeHL(H2O)5]2+, [Fe(HL)(OH)(H2O)4]+, and [Fe(HL)(OH)2(H2O)3]0 (L is an alanine ligand), the formation constants of these complexes, to determine the regions where they are dominant and their maximum degrees of accumulation, as well as to plot the diagrams of their distribution as a function of pH. It was determined that the heterovalent complex is the most stable and dominates up to pH 9.5. [ABSTRACT FROM AUTHOR]

This article focuses on the stability of error bounds, both local and global, for semi-infinite convex constraint systems in Banach spaces. We present primal characterizations of the stability of these error bounds under small perturbations. These characterizations are expressed through the directional derivatives of the functions that define the systems. It is shown that ensuring stability of the error bounds is closely tied to verifying that the optimal values of several minimax problems, formulated using the directional derivatives, remain outside a certain neighbourhood of zero. Furthermore, this stability condition only requires that all component functions of the system share the same linear perturbation. When applied to the sensitivity analysis of Hoffman's constants for semi-infinite linear systems, these stability results yield primal criteria that guarantee the uniform boundedness of Hoffman's constants under perturbations in the problem data. [ABSTRACT FROM AUTHOR]

Cyclodextrin enhances the activity of bioactive compounds through the formation of inclusion complexes (ICs), but its effect on diverse compound structures and processing methods is poorly understood. Here, our goal is to provide a comprehensive and cohesive insight into hydroxypropyl-β-cyclodextrin (HPβCD) complexation with cinnamaldehyde (CINN), citral (CIT), or their combination (MIX), prepared via kneading (KN), or freeze-drying (FD) using analytical techniques and computational simulations. Thermodynamic analysis revealed an exothermic and spontaneous (ΔG < 0) complexation process, with CINN-ICs exhibiting greater stability constants at 25 °C than CIT-ICs. Among the methods, CIT-KN displayed the highest efficiency (90.7%) and drug loading (9%), while CINN-KN showcased higher zeta potential (−23.2 mV), controlled release (35%), and antimicrobial activity (against both gram-positive and gram-negative bacteria). Computer simulations confirmed the absence of ternary complexes (CINN+CIT in HPβCD) and revealed the coexistence of association and ICs. Thermal analyses demonstrated high thermal stability (up to 207 °C) of included compounds, enhancing the suitability of these complexes for high-temperature processes. Additionally, CINN-KN incorporation into methylcellulose creates an active film, which effectively inhibited the proliferation of L. monocytogenes and S. Choleraesuis in cheeses (up to 1.3 cm halo inhibition), even following exposure to temperatures as high as 50 °C. Through combined experiments and computations, we uncovered how processing affects ICs performance with bioactive compounds, confirming their associative interactions with HPβCD. Thus, we underscore that the active function of ICs containing bioactive compounds relies not only on compound structure but also on processing methods, involving a collaborative interplay between both factors. [ABSTRACT FROM AUTHOR]

The deprotonation of acetohydroxamic acid(AHA) and its coordination chemistry with uranyl ion(\begin{document}${\mathrm{UO}}_2^{2+ }$\end{document}) in 1.0 mol/L NaClO4 has been investigated with potentiometric titration and Raman spectroscopy at 25 ℃. For the first time, the deprotonations of AHA in aqueous solutions are quantitatively investigated with potentiometric titration method. It is found that in aqueous solution AHA acts as a monobasic acid and the protonation constants calculated to be pKa1=9.24±0.11(errors are given by the HyperQuad software fitting calculations). The determined pKa1 is in good agreement with the previously reported one-step protonation. In a wide pH range from acidic to basic aqueous solutions, the two step-wise protonation of AHA has been found, at the same time, the complexation of U(Ⅵ) with AHA has been re-visited. For AHA at different degrees of deprotonation, various complexes of U(Ⅵ) with AHA at ratios of U(Ⅵ) and AHA from 1∶1 to 1∶3 are recognized by potentiometric titration method. Amongst, the 1∶1 set of complexes consists of UO2A+ and UO2(OH)A, the 1∶2 includes UO2A2 and UO2(OH)\begin{document}${\mathrm{A}}_2^{-} $\end{document}, and the 1∶3 is composed of three complexes UO2\begin{document}${\mathrm{A}}_3^{-} $\end{document}, UO2(OH)\begin{document}${\mathrm{A}}_3^{2-} $\end{document} and UO2(OH)2\begin{document}${\mathrm{A}}_3^{3-} $\end{document}. There are maybe more complex species formed during the titrations, especially in very basic solutions, but those cannot be well quantitatively characterized due to their very low solubilities. The stability constants of the mentioned seven species have been determined by HyperQuad software, with the values of UO2A+ and UO2A2 in good consistence with those reported previously. All other five new-detected complexes are detected in solutions of relatively higher pH values. In the potentiometric titrations at relatively low AHA concentration, both protons of AHA can be deprotonated to form higher proportioned UO2(OH)A in comparison with UO2A2, which is an equal species to UO2A+ in term of releasing/consuming H+ during the titration process. At greatly excessive concentrations of AHA, three complexes, UO2A+, UO2A2, and UO2\begin{document}${\mathrm{A}}_3^{-} $\end{document} are successively formed with only one proton deprotonated A− as the pH being increased; further, two species, UO2(OH)\begin{document}${\mathrm{A}}_3^{2-} $\end{document} and UO2(OH)2\begin{document}${\mathrm{A}}_3^{3-} $\end{document}, are formed with partial of the ligands in the form of completely deprotonated (OH)A2−. The Raman spectroscopic titrations show that the Raman shift of O=U=O moves to lower wavenumbers with the increase in the number of ligands, with 849 cm−1, 828 cm−1 and 807 cm−1 corresponding to the three sets of U(Ⅵ) to AHA ratios of 1∶1, 1∶2, and 1∶3, respectively. Moreover, the results demonstrate that the effect of deprotonation on the Raman shifts of uranyl ion is negligible, but the effect on the Raman intensity is significant. The almost same step-wise Raman shifts at about 21 cm−1 for the three sets of complexes, 1∶1, 1∶2 and 1∶3, indicates a similar coordination mode for all the AHA ligands with different degrees of deprotonation, which provides informative hints for the structures of the complexes.