Eyespy: June 2012

Sperm crawling and colliding—An observational study by the universities of Birmingham and Warwick has shown how sperm clumsily navigate the female reproductive tract (Proc Natl Acad Sci U S A 2012, doi:10.1073/pnas.1202934109). Researchers injected semen samples from five donors into a maze made from elastomer and glass, through which they examined the cellular swimming patterns. They found that cells would “crawl” along the walls of the lumen, and do not travel through the middle as previously thought. Sperm detached from walls at sharp turns, after sperm-sperm collisions that occurred head-on, or when attempting to overtake each other. Sperm did not perform well in specially designed circular running tracks, and tended to get trapped for extended periods of time. These results could have implications for infertility diagnostics and for novel devices used during in vitro fertilisation.

Does Achy Breaky wake the heart?—Listening to up-tempo music speeds up delivery of cardiopulmonary compressions,