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Abstract Introduction Myasthenia gravis, which initially presents with prominent distal muscle weakness, is rare and is referred to as distal myasthenia gravis. Despite its clinical significance, the diagnosis of distal myasthenia gravis is often delayed or missed owing to mild and atypical symptoms. Case report We report the case of a 52-year-old ethnic Han woman who presented with task-related isolated transient right-hand weakness that began 15 years ago and lasted for 9 years without aggravation or improvement. In subsequent years, she developed right-hand stiffness with limited dexterity. More recently, this developed into bilateral hand weakness and simultaneous generalized weakness with ambulation, prompting suspicion of myasthenia gravis. Under Hertz repetitive nerve stimulation, the right facial nerve, right accessory nerve, right ulnar nerve, right radial nerve, and right median nerve showed decrements between 19.5% and 35.4%. Tests for anti-acetylcholine receptor antibodies were positive. The patient was diagnosed with distal myasthenia gravis, which evolved into generalized myasthenia gravis. Conclusion Distal myasthenia gravis can present with isolated and transient hand weakness as a lone symptom, and can persist for years before typical myasthenia gravis symptoms appear. The inclusion of myasthenia gravis in the differential diagnosis is necessary in patients with isolated distal weakness.

Dielectronic recombination (DR) rate coefficients for C-like Ca ^14+ were measured by Wen et al. at the electron cooler storage ring in Lanzhou, China. The measured DR rate coefficients from 0 to 92 eV cover most of the DR resonances associated with the 2 s ^2 2 p ^2 → 2 s ^2 2 p ^2 and 2 s ^2 2 p ^2 → 2 s 2 p ^3 core transitions. In addition, Wen et al. reported theoretical results calculated with the Flexible Atomic Code (FAC) and AUTOSTRUCTURE (AS). However, these theoretical results show widespread and significant differences from the measured DR spectrum in both resonance energies and strengths, as well as between each other. In the present work, we uncover the reasons behind these large differences, both theoretical and experimental. The new FAC and AS results reproduce the observed spectrum in detail, especially at resonance energies below 8 eV, and they are in very close agreement with each other. The present plasma rate coefficients agree with the experimentally determined values to within 20% and 2% in the photoionized plasma (PP) and collisional ionized plasma (CP) temperature ranges, respectively. This is in contrast to the previous theoretical results, which showed differences with the experiment of up to ∼40% over the PP temperature range. The present FAC and AS results agree with each other within 5% in the PP and CP temperature ranges. Thus, the theoretical uncertainty is greatly reduced for the DR of Ca ^14+ and the present benchmarking with the experiment gives confidence to data users modeling non–local thermodynamic equilibrium plasma.