The problem: Answer a question about this article:
In the mid-1950s, Frank Burnet, inspired by a suggestion made by Niels Jerne, formulated the clonal selection theory (CST) of immunity. On the basis of CST, Burnet developed a theory of how an immune response is triggered according to the self/nonself distinction: "self" constituents (constituents of the body) do not trigger destructive immune responses, while "nonself" entities (e.g., pathogens, an allograft) trigger a destructive immune response. The theory was later modified to reflect new discoveries regarding histocompatibility or the complex "two-signal" activation of T cells. The self/nonself theory of immunity and the self/nonself vocabulary have been criticized, but remain very influential.
What triggers an immune response according to CST?
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The answer: self/nonself distinction

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In Prussia, some officials considered a war against France both inevitable and necessary to arouse German nationalism in those states that would allow the unification of a great German empire. This aim was epitomized by Prussian Chancellor Otto von Bismarck's later statement: "I did not doubt that a Franco-German war must take place before the construction of a United Germany could be realised." Bismarck also knew that France should be the aggressor in the conflict to bring the southern German states to side with Prussia, hence giving Germans numerical superiority. Many Germans also viewed the French as the traditional destabilizer of Europe, and sought to weaken France to prevent further breaches of the peace.
Who had no doubts that a Franco-German war was totally necessary?
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The answer: Chancellor Otto von Bismarck

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Roman government was headed by two consuls, elected annually by the citizens and advised by a senate composed of appointed magistrates. As Roman society was very hierarchical by modern standards, the evolution of the Roman government was heavily influenced by the struggle between the patricians, Rome's land-holding aristocracy, who traced their ancestry to the founding of Rome, and the plebeians, the far more numerous citizen-commoners. Over time, the laws that gave patricians exclusive rights to Rome's highest offices were repealed or weakened, and leading plebeian families became full members of the aristocracy. The leaders of the Republic developed a strong tradition and morality requiring public service and patronage in peace and war, making military and political success inextricably linked. Many of Rome's legal and legislative structures (later codified into the Justinian Code, and again into the Napoleonic Code) can still be observed throughout Europe and much of the world in modern nation states and international organizations.
Who elected consuls in the Roman government?
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The answer: citizens

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In recent years, Apple has seen a significant boost in sales of Macs. This has been attributed, in part, to the success of the iPod and the iPhone, a halo effect whereby satisfied iPod or iPhone owners purchase more Apple products, and Apple has since capitalized on that with the iCloud cloud service that allows users to seamlessly sync data between these devices and Macs. Nonetheless, like other personal computer manufacturers, the Macintosh lines have been hurt by consumer trend towards smartphones and tablet computers (particularly Apple's own iPhone and iPad, respectively) as the computing devices of choice among consumers.
What consumer trend has hurt many personal computer manufacturers?
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The answer:
smartphones and tablet computers