Study of three-dimensional structure in wire-array z pinches by controlled seeding of axial modulations in wire radius

Three-dimensional perturbations have been seeded in wire-array z pinches by etching 15 microm diameter aluminum wires to introduce 20% modulations in radius with a controlled axial wavelength. These perturbations seed additional three-dimensional imploding structures that are studied experimentally and with magnetohydrodynamics calculations, highlighting the role of current path nonuniformity in perturbation-induced magnetic bubble formation.     

Ultrasmall mode volumes in dielectric optical microcavities

We theoretically demonstrate a mechanism for reduction of mode volume in high index contrast optical microcavities to below a cubic half wavelength. We show that by using dielectric discontinuities with subwavelength dimensions as a means of local field enhancement, the effective mode volume (V(eff)) becomes wavelength independent. Cavities with V(eff) on the order of 10(-2)(lambda/2n)(-3) can be achieved using such discontinuities, with a corresponding increase in the Purcell factor of nearly 2 orders of magnitude relative to previously demonstrated high index photonic crystal cavities.     

Bose-Einstein condensation with attractive boundary conditions

The phenomena of Bose-Einstein condensation is discussed for particles in a box with attractive walls. Variation of the elasticity has the following effects, a) the critical temperature, fugacity, etc. vary, b) separation of phases occurs, c) condensation in one and two dimensions is possible.     

Concerning functional equations of the generalized Bol-moufang type

Aequationes mathematicae -     

Ordered differential fields

We introduce the abstract notion of an ordered differential field and show that some of the basic asymptotic growth properties of differentiable functions can be discussed within this setting. However, in order to ensure that log x → ∞ as x → ∞, we have to assume that the field of constants is archimedean.     

Statistical mechanics of quantum mechanical particles with hard cores

The definition of the thermodynamic pressure of a quantum mechanical system of hard core particles is considered for a wide variety of boundary conditions and a large class of interactions. It is shown that the pressure can be defined for elastic walls and that in the limit of an infinite system the thermodynamic pressure both exists and is independent of the coefficient of elasticity. Similarly if repulsive wall boundary conditions are used the thermodynamic pressure exists. Unfortunately it has not been possible to demonstrate that the two pressures obtained are identical but a number of their properties and interrelationships are established.     

Numbers of cubic graphs

The numbers of unlabeled cubic graphs on p = 2n points have been found by two different counting methods, the best of which has given values for p ≦ 40.     

Measurement of equilin and estrone in human plasma by capillary gas chromatography-negative ion chemical ionization mass spectrometry

A procedure is described for the analysis of the estrogens equilin and estrone in human plasma following oral administration of conjugated estrogen preparations. After enzymatic hydrolysis of the sulfate conjugates, plasma proteins are precipitated with methanol and the estrogens extracted into ethyl acetate. Derivatization with the reagent flophemesylamine converts equilin and estrone into volatile pentafluorophenyldimethylsilyl ethers ideally suited to capillary gas chromatography-negative ion chemical ionization mass spectrometry. Using a 15 meter dimethyl silicone bonded phase fused silica capillary column separation of the estrone and equilin derivatives is achieved within 9 minutes. Selected ion monitoring of the intense negative molecular ions enables levels of 1 ng.ml^?1 to be measured with coefficients of variation of 9.3 % and 14.2 % for estrone and equilin respectively. Plasma levels of the compounds are reported in two male volunteers up to 24 hours after dosing with 5 milligrams of Premarin?. (? Ayerst Laboratories Inc., New York, USA.).