Pomegranate Seed Oil and Bitter Melon Extract Affect Fatty Acids Composition and Metabolism in Hepatic Tissue in Rats

Pomegranate seed oil (PSO) and bitter melon dried fruits (BME) are used as natural remedies in folk medicine and as dietary supplements. However, the exact mechanism of their beneficial action is not known. The aim of study was to assess how the diet supplementation with PSO and/or with an aqueous solution of Momordica charantia affects the metabolism of fatty acids, fatty acids composition and the level of prostaglandin E₂ (PGE₂) in rat liver. Animals (Sprague-Dawley female rats, n = 48) were divide into four equinumerous groups and fed as a control diet or experimental diets supplemented with PSO, BME or both PSO and BME for 21 weeks. Fatty acids were determined using gas chromatography with flame ionization detection. PSO added to the diet increased the rumenic acid content (p < 0.0001) and increased accumulation of n-6 fatty acids (p = 0.0001) in hepatic tissue. Enrichment of the diet either with PSO or with BME reduced the activity of Δ⁶-desaturase (D6D) (p = 0.0019), whereas the combination of those dietary factors only slightly increased the effect. Applied dietary supplements significantly reduced the PGE₂ level (p = 0.0021). No significant intensification of the influence on the investigated parameters resulted from combined application of PSO and BME. PSO and BME have potential health-promoting properties because they influence fatty acids composition and exhibit an inhibiting effect on the activity of desaturases and thus they contribute to the reduction in the metabolites of arachidonic acid (especially PGE₂).     

The kinetics of CO2 gasification of coal chars

The gasification reactivities of three char samples derived from coals of varying ranks (“Turów” lignite, “Piast”, and “Wieczorek” sub-bituminous coals) toward CO₂ were investigated isothermally using thermogravimetric analysis. Kinetic behavior was studied at temperatures of 900, 950, and 1,000 °C under atmospheric pressure. Conditions for the chemical-controlled regime were established at these temperatures and pressure. In this paper, four kinetic models were applied to describe the varying conversion rate: volumetric model, grain model, modified volumetric model, and random pore model. From these models, only the random pore and the volumetric models positively corresponded to nearly the entire range of experimental results. Calculated values of activation energy for study samples were in the range of 180–250 kJ mol^?1, which is in accordance with other reported data. Moreover, the obtained results confirmed the significant impact of parent coal rank on its char reactivity, offering possibilities in the approximation of coal char kinetic behavior after further more detailed studies with a larger number of samples.     

Application of a likelihood ratio approach in solving a comparison problem of Raman spectra recorded for blue automotive paints

Evidential values of Raman spectra recorded for solid and metallic blue car paints were evaluated using visual comparison as well as a statistical approach, i.e. likelihood ratio (LR) test supported by Empirical Cross Entropy (ECE) results. Raman spectra were obtained using a Renishaw inVia spectrometer equipped with a confocal Leica microscope and a near infrared semiconductor laser (785 nm) as an excitation source. When a visual comparison was performed for solid paints, in 17.7% of comparisons (53 pairs out of 300) the samples were indistinguishable, whereas for metallic paints this value was 8.5% of such comparisons (37 pairs out of 435). Comparing the spectra using an LR approach was based on variables being the areas under the most significant Raman spectra bands of pigments present in the analysed samples. Proposed LR models delivered low false positive and false negative rates (for many models lower than 10%), and the ECE plots confirmed that their performance was much better than visual comparison. Copyright © 2015 John Wiley & Sons, Ltd.     

Nonlinear screening in multilayer graphene systems

Electrostatic screening in multilayer graphene is highly nonlinear due to the vanishing density of states at the Fermi level. Using a discrete model we study the charge screening normal to the layers. Our model shows a strong charge and temperature dependence and has a simple continuum limit at T=0 for undoped systems. Doped systems can exhibit more complex behavior due to minority-carrier screening. Most importantly we find that the screening length can vary more than an order of magnitude depending on the experimental conditions, reconciling the large range of screening lengths reported in previous experiments. This has important consequences for technological applications of multilayer graphene used in electrodes or transistor channels.     

Magnetic Properties of Ball-Milled Nanocrystalline Alloys Fe78B13Si9

Summary.  Magnetic properties of nanocrystalline Fe₇₈B₁₃Si₉ alloys are studied for three series prepared by ball milling starting from amorphous ribbons, crystallized ribbons, and elemental powders. Temperature variation of static magnetization results in strong ferromagnetic interaction which is weakly dependent on the initial material. Magnetic hysteresis loops show that saturation magnetization, magnetic remanence, and coercive field increase with frequency for both series of ribbon samples, whereas they decrease for alloys prepared from elemental powders. Power losses raise faster for the alloys prepared from elemental powders than for the two other alloys. Received October 5, 2001. Accepted (revised) November 12, 2001     

Long time molecular dynamics for enhanced conformational sampling in biomolecular systems

Although molecular dynamics methods are commonly used to drive biomolecular simulations, the technique provides insufficient sampling to impact studies of the 200-300 residue proteins of greatest interest. One severe limitation of molecular dynamics is that the integrators are restricted by resonance phenomena to small time steps (Delta t<8 fs) much slower then the time scales of important structural and solvent rearrangements. Here, a novel set of equations of motion and a reversible, resonance-free, integrator are designed which permit step sizes on the order of 100 fs to be used.     

Potentiometric determination of novel complexes of selected lanthanide ions with <Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N’</Emphasis>-bis(5-methylsalicylidene)-4-methyl-1,3-phenylenediamine

The stability constants of the complexes formed in the N,N’-bis(5-methylsalicylidene)-4-methyl-1,3-phenylenediamine (H₂L) and La(III), Eu(III), Gd(III), Ho(III), and Lu(III) ion systems were determined in solution with the potentiometric method. The pH-metric titrations were performed in dimethyl sulfoxide/water (v:v, 30:70) mixture at 25.0 °C in 0.1 M LiNO₃ ionic strength. The tests were performed for systems with Ln(III) to H₂L 1:2 and 1:3 molar ratio but only data of the systems with the metal/ligand ratio 1:2 were taken into calculation. The molar ratio 1:1 was not studied because of the high coordination numbers of the lanthanide ions, and inadequate donor atoms of the ligand. Computer analysis (HYPERQUAD software) of potentiometric data indicated that in solution the lanthanide (Ln) complexes exist as LnL₂, Ln(HL)₂, and Ln(H₂L)₂ forms, depending on pH unlike to the solid state where only one form of Ln(H₂L)₂ occurs. Formation constants increase with decreasing size of the Ln(III) ions. Moreover, complex formation in the Ln³⁺/H₂L systems in solution was performed using UV–Vis spectrophotometric titration.     

Long range interactions on wires: a reciprocal space based formalism

There are many atomic scale systems in materials, chemistry, and biology that can be effectively modeled as finite in two of the physical spatial dimensions and periodically replicated in the third including nanoscale metallic and semiconducting wires, carbon nanotubes, and DNA. However, it is difficult to design techniques to treat long range forces in these systems without truncation or recourse to slowly convergent supercells or computationally inefficient Poisson solvers. In this paper, a rigorous reciprocal space based formalism which permits long range forces on wires to be evaluated simply and easily via a small modification of existing methods for three dimensional periodicity is derived. The formalism is applied to determine long range interactions both between point particles using an Ewald-like approach and the continuous charge distributions that appear in electronic structure calculations. In this way, both empirical force field calculations and, for example, plane-wave based density functional theory computations on wires can be performed easily. The methodology is tested on model and realistic systems including a lithium doped carbon nanotube.     

Transport of iron ions from chloride solutions using cellulose triacetate matrix inclusion membranes with an ionic liquid carrier

In this study, liquid membranes denoted as polymer inclusion membranes (PIMs) consisting of cellulose triacetate (CTA) as a polymer matrix, o-nitrophenyl octyl ether (NPOE) as a plasticiser and phosphonium ionic liquids, trihexyltetradecylphosphonium chloride (Cyphos® IL 101) and trihexyltetradecylphosphonium bis(2,4,4-trimethylpentyl)phosphinate (Cyphos® IL 104), as carriers of metal ions were developed. The transport of Fe(II) and Fe(III) from chloride aqueous solutions across PIMs was investigated. It is shown that these phosphonium ionic liquids are effective carriers of Fe(III) ions through PIMs. While, for Fe(II), the highest value of extraction efficiency and recovery factor after 72 h does not exceed 40%, by contrast, the values of these parameters for Fe(III) transport ranged from 60% to almost 100%. Additionally, the results indicate the transport rate to be strongly influenced by the amount of carrier in the membrane. The highest initial flux of Fe(III) and permeability coefficient are noted for the membrane containing 40 mass % Cyphos® IL 101. However, it is shown that the transport of Fe(III) increases as the carrier content is increased then decreases at a content of the carrier equal to 40 mass %. It appears that the Fe(III)-carrier complex decomposes with difficulty at the interface of the membrane-receiving phase, hence leading to low values of recovery factor Fe(III).