Advanced life support equipment for nitrogen tetroxide environments

Design constraints considered in an effort to improve the self-contained atmospheric protection ensemble (SCAPE) are discussed. Emphasis is placed on overcoming the hazards of personnel engaged in orbiter crash/rescue operations. Specific topics covered include: suit material permeability; sealing of all suit penetration; and maintaining a positive pressure within the suit

Quark-gluon vertex in arbitrary kinematics

We compute the quark-gluon vertex in quenched lattice QCD, in the Landau gauge using an off-shell mean-field O(a)-improved fermion action. The complete vertex is computed in two specific kinematical limits, while the Dirac-vector part is computed for arbitrary kinematics. We find a nontrivial and rich tensor structure, including a substantial infrared enhancement of the interaction strength regardless of kinematics.Comment: 6 pages, 8 figures, talk by JIS at QCD Down Under, Adelaide, 10-19 March 200

Incorporating geostrophic wind information for improved space-time short-term wind speed forecasting

Accurate short-term wind speed forecasting is needed for the rapid development and efficient operation of wind energy resources. This is, however, a very challenging problem. Although on the large scale, the wind speed is related to atmospheric pressure, temperature, and other meteorological variables, no improvement in forecasting accuracy was found by incorporating air pressure and temperature directly into an advanced space-time statistical forecasting model, the trigonometric direction diurnal (TDD) model. This paper proposes to incorporate the geostrophic wind as a new predictor in the TDD model. The geostrophic wind captures the physical relationship between wind and pressure through the observed approximate balance between the pressure gradient force and the Coriolis acceleration due to the Earth's rotation. Based on our numerical experiments with data from West Texas, our new method produces more accurate forecasts than does the TDD model using air pressure and temperature for 1- to 6-hour-ahead forecasts based on three different evaluation criteria. Furthermore, forecasting errors can be further reduced by using moving average hourly wind speeds to fit the diurnal pattern. For example, our new method obtains between 13.9% and 22.4% overall mean absolute error reduction relative to persistence in 2-hour-ahead forecasts, and between 5.3% and 8.2% reduction relative to the best previous space-time methods in this setting.Comment: Published in at http://dx.doi.org/10.1214/14-AOAS756 the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

AN EXPERIMENTAL INVESTIGATION IN AN ATMOSPHERE ENTRY SIMULATOR OF NYLON AS AN ABLATIVE MATERIAL FOR BALLISTIC MISSILES

Investigation in atmosphere entry simulator of nylon as ablative material for ballistic missile

Lattice quark propagator with staggered quarks in Landau and Laplacian gauges

We report on the lattice quark propagator using standard and improved Staggered quark actions, with the standard, Wilson gauge action. The standard Kogut-Susskind action has errors of \oa{2} while the ``Asqtad'' action has \oa{4}, \oag{2}{2} errors. The quark propagator is interesting for studying the phenomenon of dynamical chiral symmetry breaking and as a test-bed for improvement. Gauge dependent quantities from lattice simulations may be affected by Gribov copies. We explore this by studying the quark propagator in both Landau and Laplacian gauges. Landau and Laplacian gauges are found to produce very similar results for the quark propagator.Comment: 11 pages, 15 figure

‘No Pakis at Dunkirk’: Remembering and Forgetting Force K6 in Europe 1939-1945

The 2.5 million men and women of the Indian Army who served during the Second World War are not widely known about, either in Europe or in South Asia, the anguish of Partition overlaying their memory in India and Pakistan, and the new reality of post-war Austerity Britain taking precedence over remembering colonial contributions. Among those 2.5 million, the 4,227 men of Force K6 were unique in that they spent most of their war in Britain – the heart of Empire – 630 of them having been present at Dunkirk, a British lieu de mémoire on the French coast. This thesis aims to recover their little-known story and analyse how and why they have been forgotten. The study aims to show that they are not remembered due to what Aleida Assmann has called ‘selective forgetting’ – what stays in the collective memory of a nation is what fits within their framework of culture and history. These soldiers fitted neither in the UK nor Pakistan, and so they have slipped away from official and popular memory, despite the efforts of family members and some local historians. Through several different frames of memory the story of these men and their odyssey will be presented and analysed. As this is social and cultural history, the men themselves are in the foreground, with case studies that show individual soldiers and their families, and reflect diverse aspects of their experience. Their multiple identities then and now will be analysed, and the transnational encounter which is at the core of their story will be presented, showing that the normal rules of ‘race relations’ in Britain were suspended for the duration of the war. With an eye on the dangers of instrumentalising or abusing their memory, the thesis will show how they are currently remembered, and that they could be better remembered

The spatial effect of protein deuteration on nitroxide spin-label relaxation:implications for EPR distance measurement

This work was supported by a Wellcome Trust Senior Fellowship (095062) to T.O.-H. The Authors would also like to acknowledge funding from The MRC – United Kingdom, Grant G1100021.Pulsed electron-electron double resonance (PELDOR) coupled with site-directed spin labeling is a powerful technique for the elucidation of protein or nucleic acid, macromolecular structure and interactions. The intrinsic high sensitivity of electron paramagnetic resonance enables measurement on small quantities of bio-macromolecules, however short relaxation times impose a limit on the sensitivity and size of distances that can be measured using this technique. The persistence of the electron spin-echo, in the PELDOR experiment, is one of the most crucial limitations to distance measurement. At a temperature of around 50 K one of the predominant factors affecting persistence of an echo, and as such, the sensitivity and measurable distance between spin labels, is the electron spin echo dephasing time (Tm). It has become normal practice to use deuterated solvents to extend Tm and recently it has been demonstrated that deuteration of the underlying protein significantly extends Tm. Here we examine the spatial effect of segmental deuteration of the underlying protein, and also explore the concentration and temperature dependence of highly deuterated systems.Publisher PDFPeer reviewe

Quantitative estimates of relationships between geomagnetic activity and equatorial spread-F as determined by TID occurrence levels

Using a world-wide set of stations for 15 years, quantitative estimates of changes to equatorial spread-F (ESF) occurrence rates obtained from ionogram scalings, have been determined for a range of geomagnetic activity (GA) levels, as well as for four different levels of solar activity. Average occurrence rates were used as a reference. The percentage changes vary significantly depending on these subdivisions. For example for very high GA the inverse association is recorded by a change of -33% for R-z greater than or equal to 150, and -10% for R-z < 50. Using data for 9 years for the equatorial station, Huancayo, these measurements of ESF which indicate the presence of TIDs, have also been investigated by somewhat similar analyses. Additional parameters were used which involved the local times of GA, with the ESF being examined separately for occurrence pre-midnight (PM) and after-midnight (AM). Again the negative changes were most pronounced for high GA in R-z-max years (-21%). This result is for PM ESF for GA at a local time of 1700. There were increased ESF levels (+31%) for AM ESF in R-z-min years for high GA around 2300 LT. This additional knowledge of the influence of GA on ESF occurrence involving not only percentage changes, but these values for a range of parameter levels, may be useful if ever short-term forecasts are needed. There is some discussion on comparisons which can be made between ESF results obtained by coherent scatter from incoherent-scatter equipment and those obtained by ionosondes