Chemical constituents and protective effect of Ficus ingens (Miq.) Miq. on carbon tetrachloride-induced acute liver damage in male Wistar albino rats

The aim of the present study was to investigate the chemical constituents and hepatoprotective effect of Ficus ingens (Miq.) Miq. (Moraceae) extract against carbon tetrachloride-induced acute liver damage in male Wistar albino rats. The ethanol extract of F. ingens, was subjected to phytochemical study. In addition, its acute and sub-chronic toxicities were assessed. Eight compounds were isolated from this plant and identified as β-sitosterol, β-sitosterol glucoside, chryasophanol, 7-hydroxy-2,5 dimethyl chromen-4-one, quercetin, Aloe emodin glucoside, rutin and Patuletin-3′-O-methyl-3-O-rutinoside. The structure elucidation was based on ¹H and ¹³C NMR, proton–proton correlation spectroscopy (¹H–¹H Cosy), distortionless enhancement by polarization transfer (DEPT), Heteronuclear Multiple-Quantum Correlation (HMQC), and heteronuclear multiple bond correlations spectrum (HMBC). Hepatotoxicity induced with CCl₄ was evidenced by elevation of liver marker enzymes (ALT, AST, ALP and LDH) and TB content in serum. In addition, antioxidant enzymes were drastically inhibited with significant reduction of GSH and increased LPO in liver homogenate of CCl₄-intoxicated rats. Pre-treatment with F. ingens (200 and 400 mg/kg) and silymarin (50 mg/kg) avoided the changes observed in CCl₄-intoxicated rats. In conclusion, the ethanol extract of F. ingens showed protective activity against liver injury, which might be developed into a new hepatoprotective agent.     

Nanotribology-based novel characterization techniques for the dielectric charging failure mechanism in electrostatically actuated NEMS/MEMS devices using force-distance curve measurements

The work presents a comprehensive package of novel nanoscale characterization techniques to study dielectric charging in electrostatic nano- and microelectromechanical systems (NEMS and MEMS). The proposed assessment methodologies are based on the force-distance curve (FDC) measurements performed using an atomic force microscope (AFM) to measure, for the first time, the induced surface potential and adhesive force over charged dielectric films. They were employed to study plasma enhanced chemical vapor deposition (PECVD) silicon nitride films for application in electrostatic capacitive RF MEMS switches. Three different techniques were introduced including the application of FDC measurements to study charging in bare SiN(x) films, metal-insulator-metal (MIM) capacitors, and MEMS switches. The results from the three methods were correlated and compared with the published data from other characterization techniques, mainly charge/discharge current transient (C/DCT) and Kelvin probe force microscopy (KPFM). The unique advantages of the proposed FDC-based characterization techniques are twofold. First, they can measure the multiphysics coupling between the dielectric charging phenomenon and tribological issues at the interface between the switch bridge and the dielectric surface. Second, the FDC-based techniques can measure larger levels of induced surface potential over charged dielectric films which results from the high electric field normally used to actuate MEMS switches. Based on the proposed FDC techniques, the influence of several parameters on dielectric charging/discharging processes was investigated: the dielectric film thickness, deposition conditions, substrate, and electrical stress conditions.     

Working group report: Heavy-ion physics and quark-gluon plasma

This is the report of Heavy Ion Physics and Quark-Gluon Plasma at WHEPP-09 which was part of Working Group-4. Discussion and work on some aspects of quark-gluon plasma believed to have created in heavy-ion collisions and in early Universe are reported.     

Fundamental view on the calculation of internal partition functions using occupational probabilities

From first principles, the author gathers a few general rules that need to be abided by in the calculation of the internal partition functions (IPFs) of individual molecules. These rules are violated in many schemes in the literature where occupational probabilities are used including those using the Planck–Larkin partition function (PLPF) within the chemical picture. Considering these rules is useful from conceptual and practical points of view. A solution is introduced to assure fulfilling the above mentioned rules when using occupational probabilities. Sample calculations are performed showing quantitative significance of inaccuracies caused by dishonoring such rules.     

A new acylated flavonoid tetraglycoside with anti-inflammatory activity from Tipuana tipu leaves

A new acylated kaempferol glycoside, kaempferol 3-O-α-l-rhamnopyranosyl-(1 → 6)-O-[β-d-glucopyranosyl-(1 → 2)-4-O-acetyl-α-l-rhamnopyranosyl-(1 → 2)]-β-d-galactopyranoside, has been isolated from the leaves of Tipuana tipu (Benth.) Lillo growing in Egypt, along with three known flavonol glycosides, kaempferol 3-O-rutinoside, quercetin 3-O-rutinoside (rutin) and kaempferol 3-O-[α-l-rhamnopyranosyl-(1 → 6)]-[α-l-rhamnopyranosyl-(1 → 2]-β-d-glucopyranoside. Structure elucidation was achieved through different spectroscopic methods. Structure relationship with anti-inflammatory activity using carrageenin-induced rat paw oedema model is discussed.     

Studies with 1,3-diketones: A convenient synthesis of some tetrahydro-4H-benzopyran and tetrahydroquinoline derivatives

A facile, one-step synthesis of 2-amino-5-oxo-5,6,7,8-tetrahydro-4H-benzopyran derivatives 4a-e via cyclo-addition reactions of acrylonitrile derivatives 1a-e with 1,3-cyclohexandione 2 is described. On the other hand, the reactions of 2 with the thioamides 1f-h afforded 5-oxo-5,6,7,8-tetrahydroquinoline derivatives 9a-c in good yields. The structures of the prepared compounds were established from their elemental analyses, spectroscopic data, and by their chemical transformations. © 1996 John Wiley & Sons, Inc.     

Astrophysical S-factors from asymptotic normalization coefficients

S-factors for direct capture reactions can be found at astrophysical energies from asymptotic normalization coefficients which provide the normalization of the tail of the overlap function. For example the overlap for ⁸B → ⁷Be+p defines the S-factor for ⁷Be (p, γ)⁸B. Peripheral transfer reactions offer a technique to determine these asymptotic normalization coefficients. As a test of the technique, the ¹⁶O(³He, d)¹⁷F reaction has been used to determine asymptotic normalization coefficients for transitions to the ground and first excited states of ¹⁷F. The S-factors for ¹⁶O(p, γ)¹⁷F calculated from these ¹⁷F → ¹⁶O+p asymptotic normalization coefficients are found to be in very good agreement with recent measurements. Following the same technique, the ¹⁰B(⁷Be, ⁸B)⁹Be and ¹⁴N(⁷Be, ⁸B)¹³C reactions have been used to measure the asymptotic normalization coefficient for ⁷Be(p, γ)⁸B. This result provides an indirect determination of S ₁₇(0).