This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.
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Question: As early as 1934, Popper wrote of the search for truth as "one of the strongest motives for scientific discovery." Still, he describes in Objective Knowledge (1972) early concerns about the much-criticised notion of truth as correspondence. Then came the semantic theory of truth formulated by the logician Alfred Tarski and published in 1933. Popper writes of learning in 1935 of the consequences of Tarski's theory, to his intense joy. The theory met critical objections to truth as correspondence and thereby rehabilitated it. The theory also seemed, in Popper's eyes, to support metaphysical realism and the regulative idea of a search for truth.

Answer: Whose theory of truth did Popper read with intense interest in 1935?


Question: Studies by Nathaniel Kleitman in 1938 and by Derk-Jan Dijk and Charles Czeisler in the 1990s put human subjects on enforced 28-hour sleep–wake cycles, in constant dim light and with other time cues suppressed, for over a month. Because normal people cannot entrain to a 28-hour day in dim light if at all,[citation needed] this is referred to as a forced desynchrony protocol. Sleep and wake episodes are uncoupled from the endogenous circadian period of about 24.18 hours and researchers are allowed to assess the effects of circadian phase on aspects of sleep and wakefulness including sleep latency and other functions.[page needed]

Answer: What time cycle did studies in 1938 and 1990s use on humans?


Question: By 390 BC, several Gallic tribes were invading Italy from the north as their culture expanded throughout Europe. The Romans were alerted to this when a particularly warlike tribe invaded two Etruscan towns close to Rome's sphere of influence. These towns, overwhelmed by the enemy's numbers and ferocity, called on Rome for help. The Romans met the Gauls in pitched battle at the Battle of Allia River around 390–387 BC. The Gauls, led by chieftain Brennus, defeated the Roman army of approximately 15,000 troops, pursued the fleeing Romans back to Rome, and sacked the city before being either driven off or bought off. Romans and Gauls continued to war intermittently in Italy for more than two centuries.[relevant? – discuss]

Answer:
When did the Battle of Allia River approximately end?