We believe this may have occurred by the WA1 case having exposed someone else to the virus in the period between Jan 15 and Jan 19 before they were isolated. If this second case was mild or asymptomatic, contact tracing efforts by public health would have had difficulty detecting it. After this point, community spread occurred and was undetected due to the CDC narrow case definition that required direct travel to China or direct contact with a known case to even be considered for testing. This lack of testing was a critical error and allowed an outbreak in Snohomish County and surroundings to grow to a sizable problem before it was even detected.
this is a great summary of the state of the art on using mutations to reconstruct how a disease spreads.
How did South Korea achieve this success? Sometimes it is attributed to the fancy technology that weighs and tracks the compost, and to the R.F.I.D. chips used in some municipalities to insure that households pay in proportion to the amount of waste they produce. That is important, but also I say the government shouldn’t act directly. There needs to be an intermediary between the government and the people. Groups like us.
This article explains how the Zip file format and its compression scheme work in great detail: LZ77 compression, Huffman coding, Deflate and all. It tells some of the history, and provides a reasonably efficient example implementation written from scratch in C. The source code is available in hwzip-1.0.zip.
They have hit on a low-power, lightweight self-defence system suitable for small drones. Instead of employing light or radio waves to detect incoming threats, it harnesses sound waves and the Doppler effect.
Ever wonder why are we so drawn to the snap of a potato chip or the crackle of fried chicken? Biology, psychology, and an incredible amount of engineering.
Nothing fails like success. Singapore has been spectacularly successful over the past half-century in achieving the goals its government set out and that the people overwhelmingly endorsed. But having crossed the finish line for victory at high speed, the place doesn’t seem to know what to do next except to keep on driving, pedal to the metal—which amounts to overdoing it on a higher level. Individual and social life both are pocked with unannounced tipping points, after which a productive course becomes counterproductive. Centralizing government management functions, for example, is a great idea until it isn’t, until increased transactional costs more than offset incremental efficiency gains.
more oil appeared almost every time Jerry picked up the Bible, a leather-bound copy of the New King James translation. The oil moved to the back of the book, saturated the endpapers—a heart-shaped splotch appeared over a map of Israel—and then started at the beginning, in Genesis 1. Eventually Jerry had to put the book in a Ziploc bag, and then in a large plastic bin. Jerry Pearce was a regular customer at a nearby Tractor Supply store. And he’d been seen purchasing large containers of clear oil.
Gregor J. Rothfuss 