Quantification of REM sleep without atonia: A review of study methods and meta-analysis of their performance for the diagnosis of RBD.

The present review focuses on REM sleep without atonia (RSWA) scoring methods. In consideration of the numerous papers published in the last decade, that used different methods for the quantification of RSWA, their systematic revision is an emerging need. We made a search using the PubMed, Embase, Scopus and Web of Science Databases, from 2010 until December 2021, combining the search term "RSWA" with "scoring methods", "IRBD", "alfasyn disease", and "neurodegenerative disease", and with each of the specific sleep disorders, diagnosed according to current criteria, with the identification of the references of interest for the topic. Furthermore, a Meta-analysis of the diagnostic performance of RSWA scoring methods, in terms of sensitivity and specificity, was carried out. The comparison of the hierarchical summary receiver-operating characteristic curves obtained for visual methods and that obtained for the automated REM sleep atonia index (RAI), shows substantially similar prediction areas indicating a comparable performance. This systematic review and meta-analysis support the validity of a series of visual methods and of the automated RAI in the quantification of RSWA with the purpose to guide clinicians in the interpretation of their results and their correct and efficient use within the diagnostic work-up for REM sleep behavior disorder.

Structure and emission properties of Er3Q9 (Q = 8-quinolinolate).

We report the first combined optical and structural investigation of the water free Er-quinolinolate complex, an organo-lanthanide system of interest for 1.5-microm telecom applications. Structural data demonstrate that the complex has a trinuclear structure (Er3Q9) which provides the Er metals with an octa-coordination by the organic ligand and prevents solvent and water molecules from entering the lanthanide coordination sphere. The results of the structural analysis allow us to infer that the strong Er luminescence quenching exhibited by the Er3Q9 complex is due uniquely to resonant energy transfer to the aromatic C-H vibrations of the ligand, providing the correct tools to design more efficient emitters.