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Cake day: October 22nd, 2023

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  • “The rule in question, known as Bredt’s rule in textbooks, was reported in 1924. It states that molecules cannot have a carbon-carbon double bond at the ring junction of a bridged bicyclic molecule, also known as the “bridgehead” position. The double bond on these structures would have distorted, twisted geometrical shapes that deviate from the rigid geometry of alkenes taught in textbooks.
    …A paper published by UCLA scientists in the journal Science has invalidated that idea. They show how to make several kinds of molecules that violate Bredt’s rule, called anti-Bredt olefins, or ABOs, allowing chemists to find practical ways to make and use them in reactions.”








  • 30mph (48kmh) is the minimum, cars will also be going faster than that. Also, people need to cross the street, not just walk alongside it. Regardless, whether drivers or pedestrians are the issue, accidents happen. They are more likely to happen, and more likely to be fatal as vehicle speed increases.

    From the Institute for Road Safety Research, page 2:
    “According to an overview of recent studies (Rósen et al., 2011): at a collision speed of 20 km/h nearly all pedestrians survive a crash with a passenger car; about 90% survive at a collision speed of 40 km/h, at a collision speed of 80 km/h the number of survivors is less than 50%, and at a collision speed of 100 km/h only 10% of the pedestrians survive.”

    Areas with minimum speeds of 30mph in areas with pedestrians accept that at least 1 in 10 will die. This is easily reduced to negligible fatalities by having lower speed limits. Not doing so says we care more about saving some of the drivers’ time than the lives of pedestrians.