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LOOSE ENDS. “If the Schrodinger equation doesn't care about time direction between measurements why should we?” https://lnkd.in/gDaxUYAS View in LinkedIn

THE EXERCISE. “ For the electron, superpositions of states must be available in the observer's future at least until Tn when it disappears, in order for it to move forward in time to be measured at T2, T3..... What is the difference between these two situations?” https://lnkd.in/gDaxUYAS View in LinkedIn

THE EXERCISE. “At some times T2, T3..... the physicist makes measurements and finds the two particles. For the antiparticle, moving backwards in time, superpositions of states must be available in the observer's future where it will exist at least until Tn when it appears, in order for it to move backward in time to be measured at ......T3, T2.” https://lnkd.in/gDaxUYAS View in LinkedIn

A veritable blaze of Montpellier maples planted along the upper path leading to Girona’s Sant Daniel valley. View in LinkedIn

KNOCK-OUTS. “Later, parallel mutations in the adenine DNA glycosylase gene (mutY) arose in independent lineages; these mutations approximately halved the mutation rate, apparently by knocking out a mechanism by which misincorporations of oxidized nucleotides during DNA replication (caused by the original mutT defect) were misrepaired. The resulting reduction in genetic load was estimated to be ~0.5%.” https://www.nature.com/articles/nrg3564 View in LinkedIn

ALL IS CHANGE. “Solid land has been converted into sea. Sea has been changed into land. Marine shells lie far distant from the deep, and the anchor has been found on the summit of the hills.” (Page 13, Principles of Geology: Being an Attempt to Explain the Former Changes of the Earth's Surface, by Reference to Causes Now in Operation, Volume 1, By Sir Charles Lyell, Gérard Paul Deshayes). https://lnkd.in/dZDsbmvJ View in LinkedIn

HITCHHIKING MUTATIONS. “Indeed, both mutation-rate scenarios have been observed in an E. coli population in the LTEE. After thousands of generations, a mutation in the nucleoside triphosphate pyrophosphohydrolase gene (mutT) that caused a ~150-fold increase in mutation rates spread through the population, presumably by hitchhiking with one or more beneficial mutations.” https://www.nature.com/articles/nrg3564 View in LinkedIn

RISKY STRATEGY. “In the long term, increased mutation rates are not without evolutionary risk. Opportunities for mutations that greatly improve fitness will eventually run out in the optimization regime. It may then be beneficial to compensate for a hypermutator defect and to become less evolvable in order to lower the genetic load.” https://www.nature.com/articles/nrg3564 View in LinkedIn

POSITIVE IMPACT. “However, the hypermutator subpopulation has increased evolvability because it has a much higher per-capita chance of producing the next highly beneficial mutation, or multiple beneficial mutations, than a non-mutator competitor (Fig. 3a). Thus, despite their slight fitness costs, hypermutators can sometimes hitchhike to fixation with the beneficial mutations that they generate.” https://www.nature.com/articles/nrg3564 View in LinkedIn

FREQUENCY. “Given the balance between their high rate of occurrence and small fitness costs, hypermutators might exist at frequencies of 10(-6) -10(-4) in experimental populations of E. coli.” https://www.nature.com/articles/nrg3564 View in LinkedIn