Prominence seismology using small amplitude oscillations

Quiescent prominences are thin slabs of cold, dense plasma embedded in the much hotter and rarer solar corona. Although their global shape is rather irregular, they are often characterised by an internal structure consisting of a large number of thin, parallel threads piled together. Prominences often display periodic disturbances mostly observed in the Doppler displacement of spectral lines and with an amplitude typically of the order of or smaller than 2--3 km s$^{-1}$, a value which seems to be much smaller than the characteristic speeds of the prominence plasma (namely the Alfv\'en and sound velocities). Two particular features of these small amplitude prominence oscillations is that they seem to damp in a few periods and that they seem not to affect the whole prominence structure. In addition, in high spatial resolution observations, in which threads can be discerned, small amplitude oscillations appear to be clearly associated to these fine structure constituents. Prominence seismology tries to bring together the results from these observations (e.g. periods, wavelengths, damping times) and their theoretical modeling (by means of the magnetohydrodynamic theory) to gain insight into physical properties of prominences that cannot be derived from direct observation. In this paper we discuss works that have not been described in previous reviews, namely the first seismological application to solar prominences and theoretical advances on the attenuation of prominence oscillations

Treatment and outcome of non-tuberculous mycobacterial pulmonary disease in a predominantly fibro-cavitary disease cohort

BACKGROUND: The incidence of non-tuberculous mycobacterial pulmonary disease (NTM-PD) has increased in the Netherlands. The fibro-cavitary disease manifestation predominates, as elsewhere in Europe. We studied treatment and outcome of this disease manifestation, as such data are scarce. METHODS: We conducted a retrospective study of all patients diagnosed with NTM-PD according to the American Thoracic Society statement between 2008 and 2013 in a reference clinic. RESULTS: Sixty-three patients were included. Thirty-two (51%) were females and mean age was 60.8 years. Most patients had underlying COPD (73%). M. avium complex pulmonary disease (MAC-PD) was most frequent (n = 38, 60.3%), followed by M. malmoense (n = 7) and M. kansasii (n = 6). Twenty-two patients had fibro-cavitary MAC-PD, 14 had nodular-bronchiectatic MAC-PD and 2 had other manifestations. Thirty-two (94%) patients treated for MAC-PD received a rifamycin-ethambutol-macrolide based regimen. Microbiological cure rates were lower for fibro-cavitary (52.4%) than for nodular bronchiectatic MAC-PD (100%; p = 0.03). Sixty-nine percent of treated patients experienced adverse events, most frequently gastrointestinal discomforts (71%), tinnitus (18%), hearing impairment (16%) and hepatotoxicity (18%). CONCLUSIONS: Fibro-cavitary NTM-PD remains predominant, but is now diagnosed more frequently in women. Fibro-cavitary disease is harder to cure than nodular-bronchiectatic disease. Adverse events are frequent and can necessitate cessation of treatment