Learn about various drawing approaches with a multi-color pen as this video demonstrates creative techniques and color blending. See how combining multiple ink colors can bring sketches and ...

Vikki Velasquez is a researcher and writer who has managed, coordinated, and directed various community and nonprofit organizations. She has conducted in-depth research on social and economic issues ...

An inherent principle of publication is that others should be able to replicate and build upon the authors' published claims. A condition of publication in a Nature Portfolio journal is that authors ...