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Density functional theory (DFT) computation was carried out to investigate the crystal, molecular and electronic structures of high energy crystal [2,2′-bi(1,3,4-oxadiazole)]-5,5′-dinitramide (BODN) with the pressure 0–120 GPa. The relaxed crystal structure by the GGA/PBE-TS functional matches well with the experimental data at ambient pressure condition. With the intensifying of pressure, the lattice parameters, volumes, bond lengths, H-bond energies, atomic charges, bond populations, band gaps and density of states of crystal BODN change gently. Under the pressure of 48, 104, and 107 GPa, three pressure-induced transformations occurred. The intramolecular six membered rings pose strong affect in stabilizing systems in the pressure range 0–120 GPa. Between O1 and H2 atoms, the H-bond interaction transforms into covalent interaction under the circumstance of 48 GPa. At 104 GPa, structural transformation occurs with the distortion of the intramolecular six membered ring. In addition, O1⋅⋅⋅H2 and O2⋅⋅⋅H1 have the largest H-bond energies in comparison with the others. When the pressure reaches 107 GPa, the H-bond O1⋅⋅⋅H2 is formed again with the deformation and non-coplanarity of two oxadiazoles in crystal BODN. The electrons can be moved easily based on the density of states and energy bands under high pressure. Helpful information will be conveyed by this work in the field of further analysis connected the pressure effect on molecular transformations.

Tight junctions (TJ) are multiprotein complexes that function to regulate paracellular transport of molecules through epithelial and endothelial cell layers. Many new tight junction-associated proteins have been identified in the past few years, and their functional roles and interactions have just begun to be elucidated. In this paper, we describe a novel protein LYsine-RIch CEACAM1 co-isolated (LYRIC) that is widely expressed and highly conserved between species. LYRIC has no conserved domains that would indicate function and does not appear to be a member of a larger protein family. Data from analysis of rat and human tissue sections and cell lines show that LYRIC colocalizes with tight junction proteins ZO-1 and occludin in polarized epithelial cells, suggesting that LYRIC is part of the tight junction complex. LYRIC dissociates from ZO-1 when junctional complexes are disrupted, and as tight junctions reform, ZO-1 relocalizes before LYRIC. These results suggest that LYRIC is most likely not a structural component required for TJ formation, but rather is recruited during the maturation of the tight junction complex.

The transient behavior and heat transfer for the melting of ice in porous media within a rectangular enclosure is simulated by the numerical method SIMPLE C. The solid-liquid interface becomes irregular due to the presence of porous media. The mushy zone of the finite thickness is taken into consideration in this investigation. The entire flow field is modeled by the non-Darcy model which incorporates effects of convection, inertia and boundary friction. Based upon the numerical results, the non-linear factor due to temperature-dependent density of the molten liquid could be a significant contributor to temperature field, flow field, position of interface, and capacity of heat transfer. A temperature exists on the hot side where minimum heat transfer takes place. As the Darcy number gets larger, the heat transfer gets better, the rate of melting of ice goes faster, and the interface distorts more. As time goes on, heat transfer on the hot side worsens and that on the cold side gets better.

The adsorption and oxidation of n-propanol and isopropanol at a platinum electrode have been investigated mainly by in situ FTIR spectroscopy. Molecular structure effects due to the different bonding position of the hydroxyl group to the carbon chain of the two molecules studied were demonstrated clearly. n-Propanol can dissociate into linearly bonded CO and CH3CH3 species which block the platinum surface at lower potentials; however, for steric reasons no dissociative adsorption takes place with isopropanol at a Pt electrode. CO2 was detected as the final oxidation product for both reagents. The reactive intermediate in the oxidation of n-propanol was identified as H-bonded propionic acid, and the majority intermediate in the isopropanol oxidation was acetone. It is concluded that the oxidation of n-propanol takes place via a dual path mechanism; in the case of isopropanol, a successive dehydrogenation mechanism is suggested.