Letter to the Editor Spirals and the size of the disk in EX Dra

Spirals in the disk of EX Dra

Observations at high spectral and temporal resolution are presented of the dwarf nova EX Dra in outburst. The Doppler maps are very similar to those of IP Peg in outburst as observed by Steeghs et al. (1997) and are interpreted as evidence for the presence of spiral shocks. The eclipse as seen in the red continuum indicates a disk radius of 0.31 times the orbital separation. The eclipse in the ...

Spirals and the size of the disk in EX Dra

Observations at high spectral and temporal resolution are presented of the dwarf nova EX Dra in outburst. The disk seen in the He i line reconstructed by Doppler tomography shows a clear two-armed spiral pattern pointing to spiral shocks in the disk. The Balmer and He ii maps also give evidence for the presence of spirals. The eclipse as seen in the red continuum indicates a disk radius of 0.31...

Letter to editor: the critical appraisal of “efficacy of licorice extract in the treatment of melasma: a randomized, double-blind, lacebo-controlled clinical trial”

This is a letter to editor criticizing the paper entitled “Efficacy of licorice extract in the treatment of melasma: A randomized, double-blind, placebo-controlled clinical trial”. We discuss some methodological points on external and internal validity of results. The paper suffers from lack of detailed information on sample size and power calculation to make sure generalisability of results to...

Letter to the Editor: In response to “The effect of Aromatherapy with Geranium and Lemon Essential Oil on Situational Anxiety and Physiological Indices of Patients after Coronary Angioplasty”

A letter to editor without abstract.

Effects of Tranexamic Acid on Bleeding and Hemoglobin Levels in Patients Undergoing Percutaneous Nephrolithotomy: Letter to Editor