On certain infinite semigroups of order-decreasing transformations i

We develop a Goldie theory for associative pairs and characterize associative pairs which are orders in semiprime associative pairs coinciding with their socle, and those which are orders in semiprime artinian associative pairs     

A note on life expectancy in a nonhomogeneous population

This note offers a simple mathematical model for life expectancy in a nonhomogeneous population. It is a function of life expectancy at birth and age of the population. The method is illustrated using Australian males (1961) data.     

Characterisation of aroma volatiles of indigenous alcoholic beverages: burukutu and pito

Pito and burukutu are indigenous alcoholic beverages in Nigeria, and are fermentation products of Sorghum bicolor and Sorghum vulgare. The production is similar to that of beer, which involves steeping, malting, mashing and fermenting. A total of 30 volatile organic compounds were identified by gas chromatography. These compounds can be broadly grouped into alkanols, phenols, acids, esters, ketones and aldehydes. Although few acids are present, they are dominant (30.887% and 27.669%) and followed by esters (26.467% and 27.442%) in pito and burukutu, respectively. Alkanols constitute the next dominant group after acids and esters; however, ethanol was not identified as a constituent. The health and social implication of the constituents are explained.     

Fixed point solutions of variational inequality and generalized equilibrium problems with applications

In this paper, we introduce a new iterative scheme for finding a common element of the set of fixed points of a nonexpansive mapping, the set of solution of generalized equilibrium problem and the set of solutions of the variational inequality problem for a co-coercive mapping in a real Hilbert space. Then strong convergence of the scheme to a common element of the three sets is proved. Furthermore, new convergence results are deduced and finally we apply our results to solving optimization problems and obtaining zeroes of maximal monotone operators and co-coercive mappings.     

Combined Semi-absolute FNAA and EDXRF in coal analysis

A combination of Semi-absolute Fast Neutron Activation Analysis (SFNAA) and Energy Dispersive X-ray Fluorescence (EDXRF) analysis has been employed to determine 35 inorganic elements in coals from four different mines across the minefields of Nigeria. A plot of certified against measured values of elemental constituents in a National Bureau of Standard coal reference material, SRM 1632 a, with a regression coefficient of r=0.894, is used to demonstrate the efficacy of this technique. With a complimentary application of the EDXRF technique, better precision is obtained for short-lived isotopes reducing the need for a more sophisticated transfer system and cyclic activation analysis in the situation under discussion.     

Studies on epoxidation of enantiomerically pure 2,3-dideoxy hex-2-enitols: a convenient access to highly functionalized enantiomerically pure tetrahydrofuran derivatives

A detailed comparative study on the epoxidation of enantiomerically pure allylic alcohols 8–14 derived from their respective glycals with Sharpless, m-CPBA and Camp’s reagents was carried out in order to obtain 2,3-epoxy alcohols keeping in view the versatility of these synthons in synthetic chemistry for the preparation of various molecules of biological importance by suitable chemical transformations. During the course of this study, the Sharpless asymmetric epoxidation reaction was found to be an unprecedented alternative, due to its mild reaction conditions, for synthesizing highly functionalized enantiomerically pure tetrahydrofuran derivatives. A detailed mechanistic pathway of their formation has also been studied.     

Iterative approximation of zeroes of monotone operators and system of generalized mixed equilibrium problems

In this paper, we construct a new iterative scheme by hybrid method for approximation of common element of set of zeroes of a finite family of ??-inverse-strongly monotone operators and set of common solutions to a system of generalized mixed equilibrium problems in a 2-uniformly convex real Banach space which is also uniformly smooth. Then, we prove strong convergence of the scheme to a common element of the two sets.     

An unprecedented gedunin rearrangement reaction converts a methyl group into the methylene group of a cyclopropyl ring

Herein we describe an unprecedented formation of a cyclopropane ring through the conversion of a methyl group that was not functionalized for the purpose. In a one-step reaction, 7-deacetoxy-7α-hydroxygedunin (4) afforded two new gedunin derivatives, namely 7-deacetoxy-13,14,18-cyclopropyl-7α,15β, 17ξ-trihydroxy-gedu-16-oic acid (7) and 7-deacetoxy-9,11-en-7α,15β-dihydroxygedunin (8) along with the known 7-deacetoxy-7,9-diene-15β-hydroxygedunin (5).     

Lignin nanoparticles as a novel carrier for efficacious delivery of toll like receptor 7/8 agonist: Physicochemical and in-vitro evaluation

Imidazoquinolinone (IMDQ) derivatives are known TLR7/8 agonists and are approved by the FDA for antiviral and skin cancer treatment. Their use as innate immune system activating molecules has been limited by poor pharmacokinetic properties and toxicities associated with systemic administration. In the present study, an IMDQ derivative, 1-(3-(aminomethyl) benzyl)-2-butyl-1H-imidazo[4,5-c] quinolin-4-amine (meta-aminomethyl BBIQ, 4), was encapsulated in biopolymer lignin nanoparticles (LNPs) to develop slow-release delivery system and to enhance its immune activating properties. A co-precipitation method was used to synthesize LNPs of alkali lignin. Characterization studies demonstrated the formation of spherical shaped nanoparticles of ∼150 nm size. The encapsulation efficiency and loading capacity for meta-aminomethyl BBIQ in LNPs was found to be 99% and 70%, respectively. In-vitro release studies showed 78% release over 24 h at pH 7.4 followed by sustained release. Kinetic modelling studies showed the release profile followed Weibull order kinetics with β value ≤ 0.75 corresponding to Fickian diffusion. Moreover, blank as well as meta-aminomethyl BBIQ-loaded LNPs were non-hemolytic and did not show significant cytotoxicity in RAW 264.7 and MDA-MB-23 cells at all tested concentrations. This study confirms the potential to use LNPs as a drug delivery system for immune modulators or vaccine adjuvants.