mechanical heart valves require patients to be on blood thinners for the rest of their life, bovine and porcine heart valves are most similar to human heart valves in size and shape and they have very good reliability without requiring the patient to continue taking blood thinners.
It is fascinating that we can't reproduce the mechanical properties of a small biological valve, even a dead one (they are 'killed' before they are implanted).
When they finally do figure it out, imagine all the various applications to improve the longevity of ... well, everything.
We can't even design water pipes and valves that don't degrade over time. Limescale builds up and clogs the works. There's only a tiny amount of minerals in water, and yet that happens. Blood -- as they say -- is much thicker than water, and contains components specifically designed to clot. It's not wonder that this is a tricky problem to solve.
There is also a difference in failure modes. Natural valves degrade performance overtime due to calcification of the valve, giving you warning and time to make decisions over replacement. Mechanical valves fail catastrophically by either remaining stuck open or having the valve plate shatter. If you ever stop hearing your valve click you need to get to a hospital ASAP
The real S-1 has a clickable table of contents, is easier to navigate (doesn't require back and forth clicking) and has more data (financials, capitalization, voting structure, etc)
True, this was not built with the seasoned S-1 reader in mind who already know exactly what they are looking for in a S-1. And I agree the navigation is a big problem with this version – it ought to be easier.
There are big concerns about both false positives and false negatives. The one lead ECG in the apple watch will very likely only detect afib. one lead ECG's are not diagnostic for heart attacks or any other cardiovascular disease. If you're having a heart attack and your Apple watch says you don't have a-fib, that would be a big concern.
The bitcoin ransom wallets for WannaCry were just emptied today as well. What was the time difference between these two events? It seems possible that Hutchins could have had control of the wallets and fed seized the coins.
I wonder what NASA is thinking about this? The NASA Commercial Crew program which helped fund the development of the Dragon was funded for manned flight to the ISS. I'm curious if they see this as part of the project scope?
Read the article: "By also flying privately crewed missions, which NASA has encouraged, long-term costs to the government decline and more flight reliability history is gained, benefiting both government and private missions."
The COTS and Commercial Crew program have specifically been made so that Companies can reuse the hardware for other projects as well. This is the exact thing that NASA has hoped for.
