Lipopolysaccharides of seven Bradyrhizobium strains and three whole-cell fatty acid preparations from bacteria isolated from nodules of Sarothamnus scoparius (common broom) were studied for the presence of very long chain (ω-1)-hydroxy fatty acids. Several such fatty acids were identified. Among them, straight-chain as well as mono- and dimethyl branched acids with chains in the range from 26 t...

The 3D structural control of branched polymer architecture is an important future trend in polymer production technology. The Monte Carlo simulation technique based on the random sampling technique is used to explore the effect of reactor types on the branched polymer structure, formed through freeradical polymerization that involves chain transfer to polymer, leading to simultaneous long-chain...

While the basic chemical structure of a synthetic high polymer is usually well understood, many physical properties depend on such characteristics as chain length, degree of chain branching, and molecular weight, which are not easy to specify exactly in terms of a molecular formula. Moreover, the macromolecules in a given sample are seldom uniform in chain length or molecular weight (which for ...

The self-assembly in aqueous solution of three lipopeptides obtained from Bacillus subtilis has been investigated. The lipopeptides surfactin, plipastatin and mycosubtilin contain distinct cyclic peptide headgroups as well as differences in alkyl chain length, branching and chain length distribution. Cryogenic transmission electron microscopy and X-ray scattering reveal that surfactin and plipa...

Social insect cuticular hydrocarbon (CHC) mixtures are among the most complex chemical cues known and are important in nest-mate, caste and species recognition. Despite our growing knowledge of the nature of these cues, we have very little insight into how social insects actually perceive and discriminate among these chemicals. In this study, we use the newly developed technique of differential...

This study aims to explore and model the changes in growth unit (GU) branching patterns during tree ontogeny. The question was addressed in apple trees cv. "Fuji", by analysing the relative impact of GU length and within-tree position. The development of two 6-year-old trees was recorded over 6 years. The fate of axillary buds along each GU was represented as a sequence of symbols corresponding...

Carbon 13 NMR, radiotracer and mass spectrometry studies were performed to confirm that propionate and methylmalonate are incorporated into long chain branched hydrocarbons as the methyl branch unit, to determine whether the branching methyl group was added initially or toward the end of the elongation process, to determine the precursor of methylmalonate, and to examine the metabolism of propi...