Publications by authors named "A Keimpema"

Fast radio bursts (FRBs) are flashes of unknown physical origin. The majority of FRBs have been seen only once, although some are known to generate multiple flashes. Many models invoke magnetically powered neutron stars (magnetars) as the source of the emission.

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Fast radio bursts (FRBs) are brief, bright, extragalactic radio flashes. Their physical origin remains unknown, but dozens of possible models have been postulated. Some FRB sources exhibit repeat bursts.

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Fast radio bursts are astronomical radio flashes of unknown physical nature with durations of milliseconds. Their dispersive arrival times suggest an extragalactic origin and imply radio luminosities that are orders of magnitude larger than those of all known short-duration radio transients. So far all fast radio bursts have been detected with large single-dish telescopes with arcminute localizations, and attempts to identify their counterparts (source or host galaxy) have relied on the contemporaneous variability of field sources or the presence of peculiar field stars or galaxies.

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Background And Objectives: Historically, obstructive airway diseases such as asthma and COPD are classified as different diseases. Although the definitions are clearly described, classification of patients into these traditional, clinical disease entity can be difficult. Recent evidence that there are complex, overlapping phenotypes of obstructive lung disease.

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This study assesses the validity, reliability, and responsiveness of the Dutch version of the London Chest Activity of Daily Living scale (LCADL).The English LCADL version was translated into Dutch and then back-translated to English to check if the translation was conceptually equivalent to the original LCADL.Measurement properties were evaluated in191 patients with chronic obstructive pulmonary disease (COPD) (70 males; age 62 ± 9 years; FEV1 33 ± 10% pred).

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