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Review: Living with Oil & Coal: Resource Politics & Militarization in Northeast India
Book revie
Safety of tiotropium: Indirect evidence suggests the Respimat inhaler is riskier than the Handihaler
Saul Jarcho (trans. and ed.), The clinical consultations of Francesco Torti, Malabar,FL, published on behalf of the New York Academy of Medicine by Krieger, 2000, pp. xxx, 911, illus., $125.00 (hardback 1-57524-144-7)
Louis Rosenfeld, Four centuries of clinical chemistry, Amsterdam, Gordon and Breach Science Publishers, 1999, pp. xvii, 562, illus., £91.00 (hardback 90-5699-645-2).
The origins of SOE in France
This article explores the official motivation behind the authorization in 1960 of research into the activities of the Special Operations Executive (SOE) during the Second World War by M. R. D. Foot, leading to the publication of SOE in France in 1966. The work has traditionally been viewed as the official response to critical investigative works on SOE published during the 1950s, combined with the vocal campaign of Dame Irene Ward, who made several calls in the House of Commons for an official account of SOE to be published. Material now available at the Public Record Office reveals that these were not the sole considerations in official minds, nor the most significant, concerning the possibility of publishing such a work. The foreign office was particularly concerned that Britain's contribution to wartime resistance in Europe, exemplified by SOE, was being overshadowed by both soviet propoganda, emphasizing the communist contribution to resistance, and the publicity being given to SOE's American counterpart, the Office of Strategic Services (OSS). The ‘campaign’ of Dame Irene Ward, supported by the negative slant given to SOE in the books of Jean Overton Fuller and Elizabeth Nicholas, unknowingly gave support to a frame of mind that was already in existence in favour of an unofficial account of SOE activity, albeit for different reasons
Felix Driver, Geography militant: cultures of exploration and empire, Oxford, Blackwell, 2000, pp. viii, 258, illus., £16.99 (paperback 0-631-20112-2)
Elin L Wolfe, A Clifford Barger and Saul Benison, Walter B. Cannon. Volume 2: Science and society, Boston Medical Library in the Francis A Countway Library of Medicine, 2000, pp. x, 644, illus., £19.95 (hardback 0-674-00251-2). Distributed by Harvard University Press.
Hall cascades versus instabilities in neutron star magnetic fields
Context. The Hall effect is an important nonlinear mechanism affecting the evolution of magnetic fields in neutron stars. Studies of the governing equation, both theoretical and numerical, have shown that the Hall effect proceeds in a turbulent cascade of energy from large to small scales. Aims. We investigate the small-scale Hall instability conjectured to exist from the linear stability analysis of Rheinhardt and Geppert. Methods. Identical linear stability analyses are performed to find a suitable background field to model Rheinhardt and Geppert’s ideas. The nonlinear evolution of this field is then modelled using a three-dimensional pseudospectral numerical MHD code. Combined with the background field, energy was injected at the ten specific eigenmodes with the greatest positive eigenvalues as inferred by the linear stability analysis. Results. Energy is transferred to different scales in the system, but not into small scales to any extent that could be interpreted as a Hall instability. Any instabilities are overwhelmed by a late-onset turbulent Hall cascade, initially avoided by the choice of background field, but soon generated by nonlinear interactions between the growing eigenmodes. The Hall cascade is shown here, and by several authors elsewhere, to be the dominant mechanism in this system
OXIDATION OF SILICON - THE VLSI GATE DIELECTRIC
Silicon dominates the semiconductor industry for good reasons. One factor is the stable, easily formed, insulating oxide, which aids high performance and allows practical processing. How well can these virtues survive as new demands are made on integrity, on smallness of feature sizes and other dimensions, and on constraints on processing and manufacturing methods? These demands make it critical to identify, quantify and predict the key controlling growth and defect processes on an atomic scale.The combination of theory and novel experiments (isotope methods, electronic noise, spin resonance, pulsed laser atom probes and other desorption methods, and especially scanning tunnelling or atomic force microscopies) provide tools whose impact on models is just being appreciated. We discuss the current unified model for silicon oxidation, which goes beyond the traditional descriptions of kinetic and ellipsometric data by explicitly addressing the issues raised in isotope experiments. The framework is still the Deal-Grove model, which provides a phenomenology to describe the major regimes of behaviour, and gives a base from which the substantial deviations can be characterized. In this model, growth is limited by diffusion and interfacial reactions operating in series. The deviations from Deal-Grove are most significant for just those first tens of atomic layers of oxide which are critical for the ultra-thin oxide layers now demanded. Several features emerge as important. First is the role of stress and stress relaxation. Second is the nature of the oxide closest to the Si, both its defects and its differences from the amorphous stoichiometric oxide further out, whether in composition, in network topology, or otherwise. Thirdly, we must consider the charge states of both fixed and mobile species. In thin films with very different dielectric constants, image terms can be important; these terms affect interpretation of spectroscopies, the injection of oxidant species and relative defect stabilities. This has added importance now that P-b concentrations have been correlated with interfacial stress. This raises further issues about the perfection of the oxide random network and the incorporation of interstitial species like molecular oxygen.Finally, the roles of contamination, particles, metals, hydrocarbons etc are important, as is interface roughness. These features depend on pre-gate oxide cleaning and define the Si surface that is to be oxidized which may have an influence on the features listed above
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