ElectricSteve writes: Doctors have been using hypodermic needles for more than 150 years — but syringe vaccinations could be just about to be replaced by a simple patch you can stick on your arm with no medical supervision. The microneedle patches have an array of microscopic needles on them that penetrate the skin just deep enough to dissolve and deliver a vaccine without causing any pain. There's no sharp hazardous waste left over, they're no more expensive than a syringe, and most importantly, tests on mice are showing that microneedle vaccinations are significantly longer-lasting than deeper injections delivered by syringe.
I've never been canoeing before, but I imagine there must be just a few
simple heuristics you have to remember...
Yes, don't fall out, and don't hit rocks.