Eyes on the skin. In the teamâs first experiment, the scientists were looking to see whether UV light instigated a calcium signaling response. They found nothing. But guessing that the skin might sense light like the eyes do, they added retinal, a co-factor of opsin receptors including rhodopsin.
Economy shipping takes 1 to 10 business days within the United States and 11 to 20 business days for international. Exact time depends on how far the package must travel. Standard international shipping takes 5 to 10 days.
Sellers have reported that Amazon is testing a new economy shipping option they can offer on their listings. (See update below.) Sellers began reporting a new message that appeared on August 19th offered to sellers with Professional selling plans. The Free Economy Shipping option is available for sellers for shipments to addresses in the continental United States. The new ship option has a 5-8 business day delivery service level agreement, providing you more flexibility to fulfill orders with free shipping.