Cytochrome oxidase from beef heart has been lipid-substituted with beef heart cardiolipin. The lipid phase behavior and protein aggregation state of the reconstituted complexes have been studied with 31P NMR, freeze-fracture electron microscopy, and saturation-transfer ESR of the spin-labeled protein. In the absence of salt, the lipid has a lamellar arrangement, and the protein is integrated an...

The phase diagram for diblock copolymer melts is evaluated from lattice-based Monte Carlo simulations using parallel tempering, improving upon earlier simulations that used sequential temperature scans. This new approach locates the order-disorder transition (ODT) far more accurately by the occurrence of a sharp spike in the heat capacity. The present study also performs a more thorough investi...

Quantitative deuterium nuclear magnetic resonance is used to study the freezing behavior of the water in phosphatidylcholine lamellar phases, and the effect upon it of dimethylsulfoxide (DMSO), sorbitol, sucrose, and trehalose. When sufficient solute is present, an isotropic phase of concentrated aqueous solution may coexist with the lamellar phase at freezing temperatures. We determine the com...

To investigate the molecular organization and phase behavior of physiologic lipid mixtures that contain either newly synthesized pseudoceramide or type III synthetic ceramide, various analytical techniques were used. The phase transition temperatures detected in differential scanning calorimetry analysis were 51.19 and 50.52 for the pseudoceramide-containing physiologic lipid mixture and synthe...

Several plant species reveal the tolerance to acute desiccation stress (eg. Antarctic lichens [3,4,5]). During rehydration process they can take water directly from gaseous phase in [2]. These facts focus the attention on the response of the isolated cell organellae to extreme environmental conditions. Photosynthetic membranes were selected by their importance for plant photosynthetic activity....

We have characterized the phase behavior of mixtures of the cationic surfactant cetyltrimethylammonium bromide (CTAB) and the organic salt 3-sodium-2-hydroxy naphthoate (SHN) over a wide range of surfactant concentrations using polarizing optical microscopy and X-ray diffraction. A variety of liquid crystalline phases, such as hexagonal, lamellar with and without curvature defects, and nematic,...

Highly ordered silica was synthesised by using a lamellar phase comprising the anionic fluorinated surfactant sodium perfluorooctanoate and the partially-fluorinated co-surfactant/oil 1H,1H,2H,2H-perfluorooctan-1-ol in water. The phase behaviour of this system was thoroughly analysed, and it was found that even low levels of the alcohol (<0.5 mol%) were sufficient to induce a phase change from ...

The lipid matrix present in the human stratum corneum (the thin, uppermost layer of the skin) is considered to play a crucial role in the skin barrier function. The lipid matrix consists of ceramides, cholesterol, and free fatty acids. The 13 nm lamellar phase present in the lipid matrix of the stratum corneum is very characteristic and plays an important role in the skin barrier function. One ...

Ambient-temperature fracture toughness and fatigue crack propagation behavior are investigated in a wide range of (g 1 a2) TiAl microstructures, including single-phase g, duplex, coarse lamellar (1 to 2 mm colony size (D) and 2.0 mm lamellar spacing (l)), fine lamellar (D ; 150 mm, l 5 1.3 to 2.0 mm), and a powder metallurgy (P/M) lamellar microstructure (D 5 65 mm, l 5 0.2 mm). The influences ...

– We demonstrate the possibility of a stable equilibrium multi-lamellar (“onion”) phase in pure lamellar systems (no excess solvent) due to a sufficiently negative Gaussian curvature modulus. The onion phase is stabilized by non-linear elastic moduli coupled to a polydisperse size distribution (Apollonian packing) to allow space-filling without appreciable elastic distortion. This model is comp...