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Ventricular tachyarrhythmias are potentially lethal cardiac pathologies and the commonest cause of sudden cardiac death. Efforts to predict the onset of such events are based on feature extraction from the surface ECG. T-wave alternans (TWAs) are considered a marker of abnormal ventricular function that may be associated with ventricular tachycardia (VT) and ventricular fibrillation. A novel TWA detection algorithm utilizing the continuous wavelet transform is described in this paper. Simulated ECGs containing artificial TWA were used to test the algorithm that achieved a sensitivity of 91.40% and a specificity of 94.00%. The algorithm was subsequently used to analyze the ECGs of eight patients prior to the onset of VT. Of these, the algorithm indicated that five patients exhibited TWA prior to the onset of the tachyarrhythmic events, while the remaining three patients did not exhibit identifiable TWA. Healthy individuals were also studied in which one short TWA episode was detected by the algorithm. However, closer visual inspection of the data revealed this to be a likely false positive result. Index Terms--ECG analysis, T-wave alternans (TWAs), ventricular tachyarrhithmia (VTA), wavelet transforms.

Most fluid diffusion models exhibit Fickian superdiffusive behavior due to the use of either a particle-tracking technique or an advective-diffusion equation on a computational grid. However, a new particle-tracking technique where each particle have fractional Brownian motion (fBm) has been shown to produce no Fickian diffusion. The 'non-Fickianess' of the fBm technique is inherent within the trajectories themselves, which eliminates the need for time-dependent diffusion coefficients. However, it is limited by the Hurst exponent to a maximum of unity.

Daniel Todman BRITAIN'S WAR Into battle 1937-1941 827pp. Allen Lane. 30 [pounds sterling]. 978 0 713 99927 3 Anyone hoping to revisit ITMA, Woolton pies or the documentary films of [...]

A number of papers given at the third annual summer school of the Institute of Contemporary British History have been collected in What Difference Did the War Make?, ed. Brian [...]

Winston Churchill's interest in social welfare waned in the 1930s and led to his defeat in 1945. He believed that welfare should be maintained by authority. Social progress, in his view, required a capitalist economy overseen by the state. A benign world order was dependent on the British Empire and the European balance of power.

HISTORIANS of twentieth-century British politics are fixated on party. Hence monographs on party themes abound and every leading party politician attracts a biographer. On their individual merits, such works often [...]

Reassessment of the welfare state suggests that social reform was not as radical as former historians have maintained. Social services were already developing in 1939. The Beveridge Report of 1942 was only partly implemented and subsistence benefits were rejected. Class divisions continued. The National Health Service removed charges for the middle class but failed to improve medical services for the working classes. However, reforms did reduce poverty and improved the social position of the working class.

Wavelet transform analysis offers a new approach to signal processing through its ability to decompose signals in both time and frequency. As such, it is more suited to nonstationary and intermittent signals than traditional Fourier analysis. The first part of this paper provides an introduction to the theory and signal processing properties of both continuous and discrete wavelet transform analysis. An account is then given of the application of wavelet transform analysis to a variety of experimental open channel wake flows. Feature location is undertaken using a continuous wavelet transform, and both turbulent statistical analysis and thresholding of the turbulent signal components are undertaken using a discrete wavelet transform.

Churchill and His Generals. By Raymond Callahan. (Lawrence, Kans.: University Press of Kansas, 2007. Pp. x, 310. $34.95.) Tensions between political and military leaders are almost inevitable in wartime, but [...]

David Marquand MAMMON'S KINGDOM An essay on Britain, now 276pp. Allen Lane. 20 [pounds sterling]. 978 1 84614 672 5 'If way to the Better there be', wrote Thomas Hardy, [...]

Selina Todd THE PEOPLE The rise and fall of the working class, 1910-2010 456pp. John Murray. 25 [pounds sterling]. 978 1 84854 881 7 At the start of the twentieth [...]

James H. Mills CANNABIS NATION Control and consumption in Britain, 1928-2008 292pp. Oxford University Press. 35 [pounds sterling] (US $65). 978 019 928342 2 Peter Hitchens THE WAR WE NEVER [...]

Lucy Lethbridge SERVANTS A downstairs view of twentieth-century Britain 385pp. Bloomsbury. 20 [pounds sterling]. 978 0 7475 9017 0 In 1901, there were more than 1.3 million indoor domestic servants [...]

Thirteen essays on the history of Britain since 1945, some of which originated as papers to the first summer school of the Institute of Contemporary British History, have been collected [...]

The BBC is often said to have made a crucial contribution to the unity and morale of the British people during the Second World War. As Sian Nicholas shows in [...]