275 research outputs found
Form factors of block copolymer micelles with spherical, ellipsoidal and cylindrical cores
Scattering vector dependence of the small-angle scattering from mixtures of hydrogenated and deuterated organic solvents
A Formalism for Scattering of Complex Composite Structures. 2 Distributed Reference Points
Recently we developed a formalism for the scattering from linear and acyclic
branched structures build of mutually non-interacting sub-units.{[}C. Svaneborg
and J. S. Pedersen, J. Chem. Phys. 136, 104105 (2012){]} We assumed each
sub-unit has reference points associated with it. These are well defined
positions where sub-units can be linked together. In the present paper, we
generalize the formalism to the case where each reference point can represent a
distribution of potential link positions. We also present a generalized
diagrammatic representation of the formalism. Scattering expressions required
to model rods, polymers, loops, flat circular disks, rigid spheres and
cylinders are derived. and we use them to illustrate the formalism by deriving
the generic scattering expression for micelles and bottle brush structures and
show how the scattering is affected by different choices of potential link
positions.Comment: Paper no. 2 of a serie
Анализ экономической эффективности саморегулирования в строительной отрасли
Авторами исследован вопрос экономической эффективности процессов саморегулирования в строительной отрасли в Российской Федерации с использованием сравнительного анализа норм законодательства и статистических данных. На основании анализа, проведенного авторами, показано, каким образом идея замены формы государственного участия в отношениях экономических субъектов была воплощена в принцип саморегулирования. Авторы полагают, что практика внедрения саморегулирования в строительной отрасли не может отвечать признакам экономической эффективности. Предложен вариант достижения экономической эффективности процесса саморегулирования
Interaction of membrane vesicles with the Pseudomonas functional amyloid protein FapC facilitates amyloid formation
Mixed liposomes containing gram-positive bacteria lipids:Lipoteichoic acid (LTA) induced structural changes
Lipoteichoic acid (LTA), a surface associated polymer amphiphile tethered directly to the Gram-positive bacterial cytoplasmic membrane, is a key structural and functional membrane component. Its composition in the membrane is regulated by bacteria under different physiological conditions. How such LTA compositional variations modulate the membrane structural stability and integrity is poorly understood. Here, we have investigated structural changes in mixed liposomes mimicking the lipid composition of Gram-positive bacteria membranes, in which the concentration of Bacillus Subtilis LTA was varied between 0–15 mol%. Small-angle neutron scattering (SANS) and dynamic light scattering (DLS) measurements indicated formation of mixed unilamellar vesicles, presumably stabilized by the negatively charged LTA polyphosphates. The vesicle size increased with the LTA molar concentration up to ∼6.5 mol%, accompanied by a broadened size distribution, and further increasing the LTA concentration led to a decrease in the vesicle size. At 80 °C, SANS analyses showed the formation of larger vesicles with thinner shells. Complementary Cryo-TEM imaging confirmed the vesicle formation and the size increase with LTA addition, as well as the presence of interconnected spherical aggregates of smaller size at higher LTA concentrations. The results are discussed in light of the steric and electrostatic interactions of the bulky LTA molecules with increased chain fluidity at the higher temperature, which affect the molecular packing and interactions, and thus depend on the LTA composition, in the membrane
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