We have studied molecular interactions in solutions of the protein apoferritin by static and dynamic light scattering. When plotted against the electrolyte concentration, the second osmotic virial coefficient exhibits a minimum. The ascending branch of this dependence is a manifestation of a surprisingly strong repulsion between the molecules at electrolyte concentrations about and above 0.2M, ...

Determining the mechanisms of flux through protein channels requires a combination of structural data, permeability measurement, and molecular dynamics (MD) simulations. To further clarify the mechanism of flux through aquaporin 1 (AQP1), osmotic p(f) (cm(3)/s/pore) and diffusion p(d) (cm(3)/s/pore) permeability coefficients per pore of H(2)O and D(2)O in AQP1 were calculated using MD simulatio...

Hyaluronic acid (HA) is an anionic biopolymer that is almost ubiquitous in biological tissues. An attempt is made to determine the dominant features that account for both its abundance and its multifunctional role, and which set it apart from other types of biopolymers. A combination of osmotic and scattering techniques is employed to quantify its dynamic and static properties in near-physiolog...

Iran is located in a hot and dry region. As a result of low precipitation and a vast area of salty and alkali soil, osmotic pressure is very high in most parts of the country (i.e., osmotic potential is more negative). In the present study four levels of osmotic pressure (-0.25, -0.35, -0.45, -0.50 MPa) were created artificially, by polyethylene glycol (PEG) and treatment of three seed types, n...

Drought stress influences seed germination and seedling growth of many plants. Seed coating is technique of covering seeds with adhesive agents to improve seed performance and plant establishment and could be used to alleviate the negative effects of osmotic stress. In order to solve the problem of low germination and poor vigor of sweet corn under osmotic stress conditions (0, -0.3, -0.6 and -...

Casein micelles in milk are proteinaceous colloidal particles and are essential for the production of flocculated and gelled products such as yogurt, cheese, and ice-cream. The colloidal stability of casein micelles is described here by a calculation of the pair potential, containing the essential contributions of brush repulsion, electrostatic repulsion, and van der Waals attraction. The param...

BACKGROUND AND AIMS Water adhesion forces, water absorption capacity and permeability of the pine exine were investigated to consider a possible function of sporopollenin coatings in the control of water transport. METHODS The experiments were carried out with sporopollenin capsules obtained from pine pollen consisting of an empty central capsule and two sacci. Changes in the concentration of...

aerobic rice is as useful potential in reducing of water problem. comparison and investigation of genetic differences between iranian rice varieties and aerobic rice can be useful in identification of genomic regions influencing in drought tolerance. in the present study in addition to an examination of germination genotypes under osmotic stress, allelic diversity were evaluated in 53  genotype...

This study deals with the analysis of detrimental effects a “sulfate attack” on cement mortar for different dry-wet cycles. The mass loss, tensile strength, and gas permeability coefficient were determined analyzed under exposure conditions. At same time, nitrogen adsorption (NAD), scanning electron microscopy (SEM), X-ray diffraction (XRD) techniques used to analyze corresponding variations in...