As a prelude to engineering artificial energy conversion proteins emulating biology, we examine the inclusion of a synthetic naphthoquinone amino acid in a characterized host-guest protein and determine the effects of its quinone and hydroquinone forms on the helix-coil distribution.

Gyrase is a molecular motor that harnesses the free energy of ATP hydrolysis to perform mechanical work on DNA. The enzyme specifically introduces negative supercoiling in a process that must coordinate fuel consumption with DNA cleavage and religation and with numerous conformational changes in both the protein and DNA components of a large nucleoprotein complex. Here we present a current unde...

Electron microscopy, freeze-etching, and optical diffraction show how the structure of the septate junction may provide the basis for the low-resistance pathway between the electrically coupled cells in mussel gill epithelia. Conventional electron microscopy suggests that the septa are pleated sheets that differentiate from and are structurally continuous with the junctional cell membranes. Fre...

This chapter 1 investigates the relation between the two key aspects of intelligent agents: intelligence and agent-hood. EEorts for building general architectures for intelligent agents have typically focussed on one of these aspects. The chapter rst reviews some work on cognitive architectures for intelligence and illustrates how these are being applied to physical agents. Secondly, this chapt...

transportation vehicles has motivated research in low frequency, structural-acoustic analysis. The internal sound field in the enclosed cavity is significantly affected by the acoustic modal characteristics of the cavity, by the dynamic behavior of the surrounding structure, and by the nature of the coupling of these two dynamic systems. The present work is intended to cast more light on the ac...

First-principles calculations of the free energy of several structural phases of Li are presented. The densityfunctional linear-response approach is used to calculate the volume-dependent phonon frequencies needed for computing the vibrational free energy within the quasiharmonic approximation. We show that the transformation from a close-packed structure at low temperatures to the bcc phase up...

In the past decades, mesocrystal, a kind of nanocrystals with specific crystallographic orientation, has drawn a lot of attention due to its intriguing functionalities. While the research community keeps searching for new mesocrystal systems, it is equally crucial to develop new approaches to tune the properties of mesocrystals. In this work, a self-organized two-dimensional mesocrystal compose...

The symbol of the Hessian for a static aeroelastic optimization model problem is analyzed for the optimization of a plate's shape and rigidity distribution with respect to a given cost function. The ow is modeled by the small-disturbance full-potential equation and the structure is modeled by an isotropic (von K arm an) plate equation. The cost function consists of both aerodynamic and structur...

to any given H + :P ratio. If the ratio is 3 and the permittivity 20, the distance is approximately 0.3nm. Unlike the electrochemical parameters, $“+ values do not depend on a cumulative ion effect; one proton alone at the right distance from a fixed charge will be at the potential required for synthetic activity. On these terms the rate of synthesis is determined by the number of charge<harge ...

The structural-acoustic optimization shows high potential in minimization of radiated noise especially for thin shell geometries. Acoustic design sensitivity analysis can provide information on how the geometry change affects the acoustic performance of the given structure, so it is an important step of the acoustic design and optimization processes. But the sensitivity analysis of the structur...