Dear Phenix users, This is an update for the Phenix video tutorials. We have a new tutorial explaining the use of secondary_structure_restraints https://www.phenix-online.org/documentation/reference/secondary_structure.ht..., a type of restraints especially useful at low resolution (lower than 3Å, cryo-EM map or X-ray data). References: Programming new geometry restraints: parallelity of atomic groups. Sobolev OV et al. J. Appl. Cryst. 48, 1130-1141 (2015). https://doi.org/10.1107/S1600576715010432 Use of knowledge-based restraints in phenix.refine to improve macromolecular refinement at low resolution. Headd JJ et al. Acta Cryst. D68, 381-390 (2012). https://doi.org/10.1107/S0907444911047834 Feedback about the videos is very welcome. Write an email to tutorials @phenix-online.org or use the comment section on YouTube. If you want to see a tutorial about a certain (Phenix-related) topic, let us know. Best wishes, The Phenix team ------------------------------- Overview of tutorials: https://www.phenix-online.org/documentation/reference/tutorial_channel.html You can also browse the videos on the Phenix Tutorial YouTube channel: https://www.youtube.com/c/phenixtutorials (To see subtitles, hit the cc (closed captions) button in the right bottom of the video screen. Subscribe to see the tutorial videos in your YouTube subscription feed. To get notifications about new videos, tap the bell button, which is next to the "subscribe" button.)