A variety of structural analogues of purines and pyrimidines are known to affect the growth of viruses, bacteria and other micro-organisms, plants and animals. Some of these may exert their action through being incorporated into nucleic acids in place of the natural purine or pyrimidine. Such examples are: 8-azaguanine, a structural analogue of guanine, which has been shown to replace guanine i...

By theoretical modeling and X-ray absorption spectroscopy, the local coordination structure of Zn incorporated into hydroxylapatite was examined. Density function theory (DFT) calculations show that Zn favors the Ca2 site over the Ca1 site, and favors tetrahedral coordination. X-ray absorption near edge structure (XANES) spectroscopy results suggest one dominant coordination environment for the...

The present work was aimed to design and develop self-nanoemulsifying drug delivery systems (SNEDDS) with the objective to overcome the problems associated with the delivery of talinolol, a hydrophobic and poorly bioavailable drugs having pH dependant solubility. The solubility of talinolol in various oils, surfactants, cosurfactants and aqueous phases were determined to identify and select the...

The influences of anionic sodium dodecylsulfate (SDS) and cationic Hexadecyltrimethylammonium bromide (HTAB) surfactants on the incorporation and distribution of barium hexaferrite nanoparticles in the electrodeposited CoFe-BaFe12O19 composite thin films were studied. Sulphate bathes with natural pH containing 0 to 2 g/L surfactants were used for electroplating at room temperature. Field emissi...

thyme essential oils (eo) with antimicrobial and antioxidant properties are widely used in pharmaceutical, cosmetic, and perfume industry. it is also used for flavoring and preservation of several foods. nowadays, packaging research is receiving a considerable attention due to the development of eco-friendly materials made from natural polymers such as starch and chitosan. in this study thymus ...

polyamide 6 has been widely used in food packaging applications and also green tea contains amounts of antioxidant compounds. the aim of this study was investigation of green tea effects on properties of polyamide packaging polymer. polyamide 6 was dissolved in methanol which was saturated with calcium chloride. the active packaging film was produced by incorporation of methanol green tea extra...

Selenocysteine is the only proteinogenic amino acid encoded by a recoded in-frame UGA codon that does not operate as the canonical opal stop codon. A specialized translation elongation factor, eEFSec in eukaryotes and SelB in prokaryotes, promotes selenocysteine incorporation into selenoproteins by a still poorly understood mechanism. Our structural and biochemical results reveal that four doma...

The tris-benzimidazolium cage LH(3)(3+), in MeCN solution, in the presence of OH(-), forms with Cu(I) and Ag(I) ions complexes of formula [M(I)(LH)](2+), in which each metal is linearly coordinated by two carbenes and one imidazolium N-H fragment remains intact. To achieve two-coordination, the two N-heterocyclic moieties of the cage make a saloon-door type motion, with a conformationally costl...

Protonation of [{(mu-SCH2)2N(C6H4-p-NO2)}{Fe(CO)2(PMe3)}2] in the presence of 4 equiv. of HOTf afforded two species, a micro-hydride diiron complex, the molecular structure of which was crystallographically characterized, and a micro-S-protonated species, which was readily deprotonated in the presence of pyridine.

Obi-Rakhmat Grotto is situated 100 km northeast of Tashkent, Republic of Uzbekistan. The site was first studied in the 1960s and excavations through the 1970s yielded more than 40,000 stone artifacts. Excavations were renewed in 1998 with the goal of clarifying the archaeological, geological and environmental sequence. Based on studies of the 1998-1999 collections and a sample of artifacts with...