Can we become immune to the coronavirus? What the evidence says so far | New Scientist
September 19, 2020Y-chromosomal Aaron – Wikipedia
September 19, 2020Should You Go to the Doctor’s Office During Covid-19? – Bloomberg
September 19, 2020Amazon.com Help: About KN95 Masks
September 19, 2020https://www.amazon.com/gp/help/customer/display.html?nodeId=GCY8ADPEZ623KWSN
amazon.com/AboutKN95s
The weird physics of upside down buoyancy – YouTube
September 18, 2020How to Heal a Family Rift – WSJ
September 18, 2020The Brain as Computer: Bad at Math, Good at Everything Else – IEEE Spectrum
September 14, 2020Slow cycling Numbers Don’t Lie – IEEE Journals & Magazine
September 14, 2020https://ieeexplore.ieee.org/document/7934224
Vaclav Smil
Abstract:
Some technical advances are delayed by either a failure of imagination or a concatenation of obstructive circumstances. I can think of no better example of both of these than the bicycle. . Two centuries ago, on 12 June 1817 in Mannheim, Karl Drais, a forester in Germany’s grand duchy of Baden, demonstrated for the first time his Laufmaschine (“running machine”), later also known as a draisine or hobby-horse. ….
