Microsomal nucleoprotein particles from pea seedlings

Ultracentrifugal analysis of an extract of pea epicotyls, previously freed of debris and larger particles by centrifugation at 40,000 g for 10 minutes, has revealed the presence of a major component which possesses a sedimentation coefficient of 74 S. This component constitutes about 25 per cent of the TCA-precipitable material in the clarified epicotyl extract and is estimated to make up 1 to 2 per cent of the dry weight of the original tissue. In size, chemical composition, and morphology, the 74 S component resembles the nucleoproteins of the microsomes from animal tissues. The 74 S component of pea epicotyl extracts has been purified by repeated cycles of differential centrifugation to yield a preparation which is 80 per cent homogeneous in the analytical ultracentrifuge. It has been found to contain 30 to 37 per cent RNA as judged by a variety of analytical techniques. Approximately 55 per cent of the weight of the material is protein and a further 4.5 per cent phospholipide. Electron micrographs of air-dried specimens of the purified preparation show the 74 S constituent to be flattened spheres with an average height of 180 A and an average diameter of approximately 280 A. The molecular weight of the 74 S particles is computed from sedimentation, viscosity, and partial specific volume data to be 4.5 million ± 10 per cent in agreement with the value estimated from electron micrographs. The 74 S or microsomal component of pea epicotyls is rapidly aggregated in the presence of low concentrations of Mg ions or by somewhat higher concentrations of Ca or K salts. ATP on the contrary causes resolution of electrolyte-induced microsomal aggregates with simultaneous degradation of the particles to an ultracentrifugally inhomogeneous mixture of lower molecular weight materials

A study of wing body blending for an advanced supersonic transport

Increases in supersonic cruise lift drag ratio were sought at Mach numbers 2.2 and 2.7 using wing body planform and thickness blending. Constrained twist and camber optimization was performed in the presence of nacelles. Wing and fuselage thickness distributions were optimized for either minimum volume wave drag or minimum total pressure wave drag. The zero leading edge suction lift drag ratios were determined for three wing planforms. The magnitude of the effect of leading edge suction on attainable lift drag ratio was defined on one planform and estimation of available leading edge suction was made

Crystal Structure and Magnetism of the Linear-Chain Copper Oxides Sr5Pb3-xBixCuO12

The title quasi-1D copper oxides (0=< x =<0.4) were investigated by neutron diffraction and magnetic susceptibility studies. Polyhedral CuO4 units in the compounds were found to comprise linear-chains at inter-chain distance of approximately 10 A. The parent chain compound (x = 0), however, shows less anisotropic magnetic behavior above 2 K, although it is of substantially antiferromagnetic (mu_{eff}= 1.85 mu_{B} and Theta_{W} = -46.4 K) spin-chain system. A magnetic cusp gradually appears at about 100 K in T vs chi with the Bi substitution. The cusp (x = 0.4) is fairly characterized by and therefore suggests the spin gap nature at Delta/k_{B} ~ 80 K. The chain compounds hold electrically insulating in the composition range.Comment: To be published in PR

The Origin of Primordial Dwarf Stars and Baryonic Dark Matter

I present a scenario for the production of low mass, degenerate dwarfs of mass $>0.1 M_{\odot}$ via the mechanism of Lenzuni, Chernoff & Salpeter (1992). Such objects meet the mass limit requirements for halo dark matter from microlensing surveys while circumventing the chemical evolution constraints on normal white dwarf stars. I describe methods to observationally constrain this scenario and suggest that such objects may originate in small clusters formed from the thermal instability of shocked, heated gas in dark matter haloes, such as suggested by Fall & Rees (1985) for globular clusters.Comment: TeX, 4 pages plus 2 postscript figures. To appear in Astrophysical Journal Letter

Resonance production from jet fragmentation

Short lived resonances are sensitive to the medium properties in heavy-ion collisions. Heavy hadrons have larger probability to be produced within the quark gluon plasma phase due to their short formation times. Therefore heavy mass resonances are more likely to be affected by the medium, and the identification of early produced resonances from jet fragmentation might be a viable option to study chirality. The high momentum resonances on the away-side of a triggered di-jet are likely to be the most modified by the partonic or early hadronic medium. We will discuss first results of triggered hadron-resonance correlations in Cu+Cu heavy ion collisions.Comment: Hot Quarks Colorado 2008 Proceedings, 4 pages 5 figure

From 'River Cottage' to 'Chicken Run': Hugh Fearnley-Whttingstall and the class politics of ethical consumption

Lifestyle television provides a key site through which to explore the dilemmas of ethical consumption, as the genre shifts to consider the ethics of different consumption practices and taste cultures. UK television cook Hugh Fearnley-Whittingstall's TV programmes offer fertile ground not only for thinking about television personalities as lifestyle experts and moral entrepreneurs, but also for thinking about how the meanings and uses of their television image are inflected by genre. In this article we explore how the shift from the lifestyled downshifting narrative of the River Cottage series to the 'campaigning culinary documentary' Hugh's Chicken Run exposes issues of celebrity, class and ethics. While both series are concerned with ethical consumption, they work in different ways to reveal a distinction between 'ethical' and 'unethical' consumption practices and positions - positions that are inevitably classed

Microscopic Electron Models with Exact SO(5) Symmetry

We construct a class of microscopic electron models with exact SO(5) symmetry between antiferromagnetic and d-wave superconducting ground states. There is an exact one-to-one correspondence between both single-particle and collective excitations in both phases. SO(5) symmetry breaking terms can be introduced and classified according to irreducible representations of the exact SO(5) algebra. The resulting phase diagram and collective modes are identical to that of the SO(5) nonlinear sigma model.Comment: 5 pages, LATEX, 4 eps fig