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While many numerical and experimental works were focused on water-ethanol mixtures at low ethanol concentration, this work reports predictions of a few physical properties (thermodynamical, interfacial, dynamical, and dielectrical properties) of water-ethanol mixture at high alcohol concentrations by means of molecular dynamics simulations. By using a standard force field a good agreement was found between experiment and molecular simulation. This was allowed us to explore the dynamics, structure, and interplay between both hydrogen-bonding networks of water and ethanol. [ABSTRACT FROM AUTHOR]

In this Letter, we show how the grooved helical structure of actin microfilaments (F-actin) interacting with mixed fluid lipid bilayers leads to handedness-independent lD lipid bilayer undulations coupled to longitudinal in-plane ordering of the microfilaments. This longitudinal ordering is forced by the emerging in-plane compression and curvature energy terms of the straight 1D bilayer undulation wave fronts. Thereby, adjacent helices are set into registry along their long axis in their monolayer and π shifted between adjacent monolayers. An ordered composite multilamellar structure emerges by alternate stacking of these lipid bilayers and monolayers of F-actin. This two-dimensionally ordered system has the symmetries of a centered rectangular columnar liquid crystal, the straight lD wave fronts playing the role of the classical molecular columns. [ABSTRACT FROM AUTHOR]

Highlights: [•] Gold nanorods functionalization with different peptides. [•] A mechanism of the interaction driving the self-assembling. [Copyright &y& Elsevier]

Abstract: The behavior of the two major galactolipids of wheat endosperm, mono- (MGDG) and di-galactosyldiacylglycerol (DGDG) was studied in aqueous dispersion and at the air/liquid interface. The acyl chains of the pure galactolipids and their binary equimolar mixture are in the fluid or liquid expanded phase. SAXS measurements on liquid-crystalline mesophases associated with the electron density reconstructions show that the DGDG adopts a lamellar phase Lα with parallel orientation of the headgroups with respect to the plane of the bilayer, whereas MGDG forms an inverse hexagonal phase HII with a specific organization of galactosyl headgroups. The equimolar mixture shows a different behavior from those previously described with formation of an Im3m cubic phase. In comparing monolayers composed of the pure galactolipids and their equimolar mixtures, PM-IRRAS spectra show significant differences in the optical properties and orientation of galactosyl groups with respect to the interface. Furthermore, Raman and FTIR spectroscopies show that the acyl chains of the galactolipid mixture are more ordered compared to those of the pure components. These results suggest strong interactions between MGDG and DGDG galactosyl headgroups and these specific physical properties of galactolipids are discussed in relation to their biological interest in wheat seed. [Copyright &y& Elsevier]

The first developments for a new integrated photonics using optical evanescent coupling from organic microstructures to fibres of hybrid nanotubes (NT) are reported. Microstructures are organic discs acting as photon reservoirs, integrated on a photonic chip fabricated by microtechnologic processes. Biomimetic peptidic/silica NT are realised by molecular self-assembly allowing centimetres long fibres of NT. Such heterostructures have been included directly on the organic as an innovative solution based on an NT in situ chip-approach. The latter allowed us to obtain an adequate evanescent coupling localised between micronic-discs and fibrous structures. Highlighted is a specific photonic propagation along various heterostructured-NT-fibres featuring distances beyond the centimetre and losses inferior to 1 dB/cm. It presents an advantageous confinement marked with strong energy localisations between NT. [ABSTRACT FROM AUTHOR]

We report a practical and novel approach based on reproducible fluidic mechanisms coupled with silica nano-particles for the development of nano-optical-connections directly on organic integrated photonic chips. Silica nano-ridge waveguides have been shaped with various widths ranging between 50 nm and 200 nm and with about one hundred micrometers length. An effective nano-photonic coupling mechanism has been demonstrated and a sub-wavelength propagation regime obtained between four perpendicular organic rib tapers and two parallel waveguides with respectively curved and straight silica nano-ridges configurations. The specific silica nano-ridge-waveguides structures show off optical propagation losses ranging between 37 and 68dB/mm at visible and infra-red wavelengths respectively. Such flexible devices offer a versatile fabrication process and present great potential regarding future applications for shaping nano-connections and integrating high-density networks. Indeed originally segmented optical circuits tapers, lines, plots or any pre-formed photonics structures could thus be combined. [ABSTRACT FROM AUTHOR]

Abstract: Starting from the generalised four-slab layer in electromagnetic theory and photonics, this paper introduces a convenient method and a new proper change of variables in order to obtain the global analytical expressions of the power flows in such multilayer structures for the TE m and TM m optical modes. These proper changes of variables and relevant definitions of apt new parameters (Θ, W, Y and ξ) allow us to derive and shape new general analytical formulations and normalizations in terms of power flows. According to such specific parameters, it can be noted that such a comprehensive result brings in an effective criteria form of the classical results ascribed to three-slab problems. Moreover, we have verified with specific cases regarding three-slab problems the validity of our new global frame for analysing power flows. It clearly appears that classical three-slab-waveguide expressions directly stem from our formulation. Naturally, this global four-slab-waveguides approach can be used directly to the analytical calculus of corresponding ratios of power between the different layers, such as the core compared with buffer layers as upper and lower claddings. [Copyright &y& Elsevier]

Polymorphism of trilaurin mixed with 4% of cholesterol was studied with a setup coupling calorimetry and phase characterisation by in-situ X-ray diffraction (Microcalix). Four polymorphic forms were identified. Monotropic and enantiotropic transitions were identified from the reconstruction of Gibbs free energy diagram which allows the control of trilaurin polymorphism. [ABSTRACT FROM AUTHOR]

A practical concept is reported based on reproducible fluidic mechanisms coupled with silica nano-particles for the development of nano-optical-connections directly on organic integrated photonic chips. Silica nano-rib waveguides have been shaped with various widths ranging between 50 and 300 nm and about 100 µm in length. An effective nano-photonic coupling mechanism has been demonstrated and a sub-wavelength propagation regime obtained between two organic rib tapers and waveguides with a perpendicular and a parallel configuration, respectively. The specific silica nano-rib-waveguide structures show off optical losses propagation ranging around 37–68 dB/mm at visible and infrared wavelengths. Such flexible devices offer versatile fabrication control by changing, respectively, nano-particles and surfactant concentrations. Thus, they present great potential regarding future applications for shaping nano-connections and high-density network integrations between original optical segmented circuits such as plots, lines or any pre-formed photonic structures. [ABSTRACT FROM AUTHOR]

We show that the evaporation of surfactant solutions confined in quasi-two-dimensional porous media creates micron-sized labyrinthine patterns composing the walls of a centimeter-sized maze. These walls are made of solid deposits formed during drying via a sequence of individual Haines jumps occurring at the pore scale. We rationalize this process driven by simple iterative rules with a cellular automaton that acts as a maze generator. This model well describes the formation dynamics and final structure of an experimental maze as functions of the wettability heterogeneities of a porous medium and its geometry. Also, our findings unveil the crucial role of two geometric dimensionless quantities that control the structural order of a maze. [ABSTRACT FROM AUTHOR]