Here is a question about this article: Immanuel Velikovsky is an example of a recent scientific exoheretic; he did not have appropriate scientific credentials or did not publish in scientific journals. While the details of his work are in scientific disrepute, the concept of catastrophic change (extinction event and punctuated equilibrium) has gained acceptance in recent decades.
What is the answer to this question: What medium did Immanuel Velikovsky not publish his works in that is accepted practice?
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So... scientific journals

Here is a question about this article: In addition to the use of the multiprotein complexes listed above, Gram-negative bacteria possess another method for release of material: the formation of outer membrane vesicles. Portions of the outer membrane pinch off, forming spherical structures made of a lipid bilayer enclosing periplasmic materials. Vesicles from a number of bacterial species have been found to contain virulence factors, some have immunomodulatory effects, and some can directly adhere to and intoxicate host cells. While release of vesicles has been demonstrated as a general response to stress conditions, the process of loading cargo proteins seems to be selective.
What is the answer to this question: What other method does Gram-negative bacters use to release material?
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So... the formation of outer membrane vesicles

Here is a question about this article: With the collapse of Roman rule in the early 5th century, London ceased to be a capital and the walled city of Londinium was effectively abandoned, although Roman civilisation continued in the St Martin-in-the-Fields area until around 450. From around 500, an Anglo-Saxon settlement known as Lundenwic developed in the same area, slightly to the west of the old Roman city. By about 680, it had revived sufficiently to become a major port, although there is little evidence of large-scale production of goods. From the 820s the town declined because of repeated Viking invasions. There are three recorded Viking assaults on London; two of which were successful in 851 and 886 AD, although they were defeated during the attack of 994 AD.
What is the answer to this question: How many known attacks on London did the Vikings commit?
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So...
three