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Intense amplified spontaneous emission is generated in generally axial directions in a recombining uniform Z pinch. This effect allows the generation of highly efficient soft x-ray beams, including the intense xenon-band emission at 134 ?, of interest for extreme ultraviolet lithography. We discuss the characteristics of this source, including optimization of the xenon-helium mix and measurements of source size, brightness, and positional and amplitude stability. The issues involved in increasing power to the lithography class by an increase in the repetition rate are discussed. The life and operating costs of a lithography source are considered.

In this article we show that a channel complex of cooperatively interacting subunits can produce a power law spectrum with the slope of the spectrum depending on the strength of the cooperative interaction. The effects of cooperativity are explored via a computational model of a calcium-regulated cation channel for which new data is presented. The results, which concern "flickering" conductances, are correlated with prior work on critical fluctuations in the Ising model of ferromagnetism.

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An oscillator pore is identified that generates intermittent, large amplitude, ionic current in the plasma membrane. The pore is thought to be composed of 10-12 units of subunit c of ATP synthase. Pore opening and closing is a co-operative process, dependent on the release, or binding, of as many as six calcium ions. This mechanism suggests a more general method of co-operative threshold detection of chemical agents via protein modification, the output being directly amplified in a circuit. Here the authors describe steps in the development of a sensor of chemical agents. The subunit c pore in a lipid bilayer spans a nanometer-scale hole in a silicon nitride barrier. Either side of the barrier are electrolyte solutions and current through the pore is amplified by circuitry. The techniques of laser ablation, electron beam lithography and ion beam milling are used to make successively smaller holes to carry the lipid patch. Holes of diameter as small as 20 nm are engineered in a silicon nitride barrier and protein activity in lipid membranes spanning holes as small as 30 nm in diameter is measured. The signal-to-noise ratio of the ionic current is improved by various measures that reduce the effective capacitance of the barrier. Some limits to scale reduction are discussed.

We consider an ancient protein, and water as a smooth surface, and show that the interaction of the two allows the protein to change its hydrogen bonding to encapsulate the water. This property could have made a three-dimensional microenvironment, 3-4 Gyr ago, for the evolution of subsequent complex water-based chemistry. Proteolipid, subunit c of ATP synthase, when presented with a water surface, changes its hydrogen bonding from an a-helix to b-sheet-like configuration and moves away from its previous association with lipid to interact with water surface molecules. Protein sheets with an intra-sheet backbone spacing of 3.7 Å and inter-sheet spacing of 6.0 Å hydrogen bond into long ribbons or continuous surfaces to completely encapsulate a water droplet. The resulting morphology is a spherical vesicle or a hexagonal crystal of water ice, encased by a skin of subunit c. Electron diffraction shows the crystals to be highly ordered and compressed and the protein skin to resemble b-sheets. The protein skin can retain the entrapped water over a temperature rise from 123 to 223 K at 1!10 K4 Pa, whereas free water starts to sublime significantly at 153 K.

An approach to a high-repetition ignition facility based on direct drive with the krypton-fluoride laser is presented. The objective is development of a "Fusion Test Facility" that has sufficient fusion power to be useful as a development test bed for power plant materials and components. Calculations with modern pellet designs indicate that laser energies well below a megajoule may be sufficient. A smaller driver would result in an overall smaller, less complex and lower cost facility. While this facility might appear to have most direct utility to inertial fusion energy, the high flux of neutrons would also be able to address important issues concerning materials and components for other approaches to fusion energy. The physics and technological basis for the Fusion Test Facility are presented along with a discussion of its applications.

A unique all solid-state pulsed power system has been tested at the Naval Research Laboratory that produced 200 kV, 4.5 kA, and 300 ns pulses, continuously for more than 11,500,000 shots into a resistive load at a repetition rate of 10 pps. The Marx has an efficiency of 80% based on calorimetric measurements. This pulser is used to evaluate components and advance solid state designs for a next generation solid-state pulsed power system to drive an electron beam pumped KrF laser system for inertial fusion energy. The solid state pulser, designed and constructed by PLEX LLC, consists of a 12 stage Marx, coupled with a 3rd harmonic stage to sharpen the Marx output waveforms, a main magnetic switch, a compact pulse forming line used as a transit time isolator, and a resistive load. Each Marx stage uses an APP Model S33A compact high voltage switch that consists of 12 series connected thyristors. A life test on individual thyristors showed operation of > 300 M shots at 20 Hz without failure.