Complete Atrioventricular Block: A Rare Complication of MitraClip Implantation.

MitraClip (Abbott Vascular, Inc., Santa Clara, California) has emerged as a viable alternative for treatment of symptomatic severe mitral regurgitation. Conduction abnormalities are not a known complication of this procedure.

First layer compression and transition to standing second layer of terephthalic acid on Cu(100).

Terephthalic acid on metal surfaces is a system of high interest for interfacial layers as well as for use in generating surface nanostructures by supramolecular self-assembly. Here we demonstrate structural transitions upon compression of the first layer as well as a significant transition from a flat lying chemisorbed first monolayer to a standing second layer. The second layer structure is stable at 150 °C, but a weakly bound state is observed to desorb molecularly below that temperature, likely a transient mobile state during annealing.

Adsorption and bonding of first layer and bilayer terephthalic acid on the Cu(100) surface by high-resolution electron energy loss spectroscopy.

The self-assembled and highly ordered first layer of terephthalic acid on Cu(100) as well as its bilayer on the same surface are studied here using high-resolution electron energy loss spectroscopy (HREELS), Auger electron spectroscopy, and low energy electron diffraction. These experiments show completion of the first layer before growth of the second layer. HREELS measurements show that the first layer of the acid deprotonates, which is seen in the absence of the OH stretching mode for the acid groups.