Kinetic experiments with a substrate series of phenylacetyl-arylamides reveal that at least one polar group in the amine moiety is required for the proper orientation of the substrate in the large nucleophile-binding subsite of penicillin acylase of Escherichia coli. Quantum mechanical molecular modelling of enzyme-substrate interactions in the enzyme active site shows that in the case of subst...

Drops of active liquid crystal have recently shown the ability to self-propel, which was associated with topological defects in the orientation of active filaments [Sanchez et al., Nature 491, 431 (2013)]. Here, we study the onset and different aspects of motility of a three-dimensional drop of active fluid on a planar surface. We analyze theoretically how motility is affected by orientation pr...

This paper presents the design of orientation stages for high-resolution imprint lithography machines. These machines implement a new lithography process known as Step and Flash Imprint Lithography (SFIL) and are intended for 1) sub 100 nm imprint demonstrations on flat substrates and 2) investigation of potential defect propagation during step and repeat imprinting. SFIL is an imprint lithogra...

BACKGROUND The effects of microchannel diameter in hydroxyapatite (HAp) substrates on osteoblast behavior were investigated in this study. Microchannels of 100, 250 and 500 μm diameter were created on hydroxyapatite disks. The changes in osteoblast precursor growth, differentiation, extra cellular matrix (ECM) secretion and cell attachment/orientation were investigated as a function of microcha...

This paper presents the design of orientation stages for high-resolution imprint lithography machines. These machines implement a new lithography process known as Step and Flash Imprint Lithography (SFIL) and are intended for 1) sub 100 nm imprint demonstrations on flat substrates and 2) investigation of potential defect propagation during step and repeat imprinting. SFIL is an imprint lithogra...

Mu DNA transposition from a negatively supercoiled DNA substrate requires interaction of an enhancer element with the left (attL) and right (attR) ends of Mu. The orientation of the L and R ends with respect to each other (inverted) and with respect to the enhancer is normally inviolate. We show that when the enhancer is provided in trans as a linear fragment, the head to head orientation of th...

Though both the crystal structure and molecular orientation of organic semiconductors are known to impact charge transport in thin-film devices, separately accessing different polymorphs and varying the out-of-plane molecular orientation is challenging, typically requiring stringent control over film deposition conditions, film thickness, and substrate chemistry. Here we demonstrate independent...

In this letter, we performed molecular dynamics simulations of ice nucleation on a rigid surface model cubic zinc blende structure with different dipole strength and orientation. It follows that, despite the excellent lattice match between substrates, happened only when interfacial water molecules (IWs) have same or similar orientations as that in ice. The free energy landscapes revealed for su...

The growth of GaN bulk crystals via the HVPE process and the manufacturing of orientation controlled substrates from the GaN crystals are presented. An HVPE process has been produced for growth of bulk GaN on sapphire with an AlN interfacial seed layer. This process has allowed for the production of GaN substrates up to 2 inches in diameter. Due to the stress associated with the growth of GaN o...

Biphenyl dioxygenase is the enzyme that catalyzes the stereospecific dioxygenation of the aromatic ring. This enzyme has attracted the attention of researchers due to its ability to oxidize polychlorinated biphenyls, which is one of the serious environmental contaminants. We determined the crystal structure of the terminal oxygenase component of the biphenyl dioxygenase (BphA1A2) derived from R...