Q: Did a recent study in Denmark show that face masks are useless for COVID-19?
A: No. The study found that face masks did not have a large protective effect for wearers — not that masks provide no protection at all or don’t offer benefits to others.
Q. Is it true that federal agents arrested Harvard professor Charles Lieber for creating the coronavirus?
A: No. Lieber, a nanoscientist, was charged for lying about his participation in a Chinese recruitment program and his affiliation with a Chinese university. He is not accused of being a spy and has no connection to the new coronavirus.
Q: When is the human heart fully developed, and when are heartbeats audible during pregnancy?
A: A developing heart has all of its primary structures after about nine weeks of pregnancy. Some forms of ultrasound can detect cardiac activity in an embryo in the sixth week, but a heartbeat wouldn’t be audible until about 10 weeks on a Doppler fetal monitor.
Q: Does the National Institutes of Health fund research on human-animal chimeras, or organisms that are part-human, part-other animal?
A: With some exceptions, the NIH doesn’t fund research on human-animal chimeras. But the agency has proposed a rule to widen the scope of research it funds in this area.