AIMS To investigate the ability of patients with Parkinson's disease to perform a rotation around the longitudinal axis of the body. Three questions were raised. Is body rotation impaired in Parkinson's disease? Is there a level of the kinematic chain from the head to the foot at which the impairment is more severe? Is the deficit related to the general slowness of movement in Parkinson's disea...

The process of wave equation continuation (migration) is adapted for refraction data in order to produce velocity-depth models directly from the recorded data. The procedure consists of two linear transformations: a slant stack of the data produces a wave field in the p T plane which is then downward continued using T = 0 as the imaging condition. The result is that the data wave field is linea...

Fig 1: Midsagittal section through brainstem showing prominent midbrain atrophy without pontine atrophy resembling a hummingbird (arrow showing the beak) and a penguin Fig 2: Axial MRI showing selective atrophy of the midbrain tegmentum, with relative preservation of the tectum and cerebral peduncles resembling Mickeymouse (Arrow) A fifty year old male was brought by his wife with insidious ons...

Delays in the initiation of a movement response and slowness during movement are among the hallmark motor symptoms in patients with Parkinson's disease (PD). These impairments may result from deficits in neural structures related to perception, response programming, response initiation, or a combination of all three. However, the relative impact of each process on movement control in PD is stil...

Fast Fourier transform (FFT) coprocessor, having significant impact on the performance of communication systems, hasbeen a hot topic of research for many years. The FFT function consists of consecutive multiply add operations over complex numbers, dubbed as butterfly units. Applying floating-point (FP) arithmetic to FFT architectures, specifically butterfly units, has become more popular recent...

Several recent studies have used the coherence of seismic noise between stations to retrieve the phase slowness and attenuation. However, there is considerable debate on the feasibility of attenuation retrieval, its interpretation, and its dependence on the noise directionality and has been the subject of several analytical and numerical studies. In this article, we perform a detailed analysis ...

Strong refraction of waves in the migration velocity model introduces kinematic artifacts coherent events not corresponding to actual reflectors into the image volumes produced by prestack depth migration applied to individual data bins. Because individual bins are migrated independently, the migration has no access to the bin component of slowness. This loss of slowness information permits eve...

Examination of mood and behaviour changes after frontal damage may contribute to understanding the functional role of distinct prefrontal areas in depression and anxiety. Depression and anxiety disorders, symptoms, and behaviour were compared in eight patients with single lateral and eight patients with single medial frontal lesions matched for age, sex, race, education, socioeconomic status, s...