Conventional and reciprocal approaches to the inverse dipole localization problem for N(20)-P (20) somatosensory evoked potentials.

The non-invasive localization of the primary sensory hand area can be achieved by solving the inverse problem of electroencephalography (EEG) for N(20)-P(20) somatosensory evoked potentials (SEPs). This study compares two different mathematical approaches for the computation of transfer matrices used to solve the EEG inverse problem. Forward transfer matrices relating dipole sources to scalp potentials are determined via conventional and reciprocal approaches using individual, realistically shaped head models.

Do people with mild COPD benefit from early pulmonary rehabilitation programmes?

People with mild to moderate COPD usually receive information about their condition from GPs or practice nurses, while those with moderate to severe disease have access to pulmonary rehabilitation programmes. This article describes a pilot of a pre-pulmonary rehabilitation course that aimed to standardise information for people with mild disease.

Prevention of venous thromboembolism.

Venous thromboembolism (VTE) is a preventable cause of significant morbidity and mortality in hospitalized patients, especially in the perioperative period. After identifying the risk factors, it is possible to stratify patients into groups based on their degree of risk for developing VTE. Methods available for the prevention of VTE vary in degree of intensity, efficacy, and side effects.

Dipole localization using beamforming and RAP-MUSIC on simulated intracerebral recordings.

Interpreting intracerebral recordings in the search of an epileptic focus can be difficult because the amplitude of the potentials are misleading. Small generators located near the electrode site generate large potentials, which could swamp the signal of a nearby epileptic focus. In order to address this problem, two inverse problem algorithms, beamforming and recursively applied and projected multiple signal classification (RAP-MUSIC), were used with simulated intracerebral potentials to calculate equivalent dipole positions.

A comparison of monodomain and bidomain reaction-diffusion models for action potential propagation in the human heart.

A bidomain reaction-diffusion model of the human heart was developed, and potentials resulting from normal depolarization and repolarization were compared with results from a compatible monodomain model. Comparisons were made for an empty isolated heart and for a heart with fluid-filled ventricles. Both sinus rhythm and ectopic activation were simulated.