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Nanjing has been the educational centre in southern China for more than 1700 years. There are 75 institutions of higher learning till 2013. The number of National key laboratories, National key disciplines and the academicians of Chinese Academy of Sciences and Chinese Academy of Engineering all rank third in the nation. It boasts some of the most prominent educational institutions in the region, some of which are listed as follows:
What is Nanjing's nationwide ranking for National key laboratories?
A: third

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Vaccines rely on immune modulation or augmentation. Vaccination either excites or reinforces the immune competence of a host to ward off infection, leading to the activation of macrophages, the production of antibodies, inflammation, and other classic immune reactions. Antibacterial vaccines have been responsible for a drastic reduction in global bacterial diseases. Vaccines made from attenuated whole cells or lysates have been replaced largely by less reactogenic, cell-free vaccines consisting of purified components, including capsular polysaccharides and their conjugates, to protein carriers, as well as inactivated toxins (toxoids) and proteins.
What do polysaccharides need to work?
A: unanswerable

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On July 17, 2012, the CRTC approved the shut down of CBC's analogue transmitters, noting that "while the Commission has the discretion to refuse to revoke broadcasting licences, even on application from a licensee, it cannot direct the CBC or any other broadcaster to continue to operate its stations and transmitters." On July 31, 2012, at around 11:59 p.m. in each time zone, the remaining 620 analogue transmitters were shut down, leaving the network with 27 digital television transmitters across the country, and some transmitters operated by some affiliated stations.
When did the CRTC order the shutdown of the analogue transmitters?
A: unanswerable

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Roman Catholicism was the sole established religion in the Holy Roman Empire until the Reformation changed this drastically. In 1517, Martin Luther challenged the Catholic Church as he saw it as a corruption of Christian faith. Through this, he altered the course of European and world history and established Protestantism. The Thirty Years' War (1618–1648) was one of the most destructive conflicts in European history. The war was fought primarily in what is now Germany, and at various points involved most of the countries of Europe. The war was fought largely as a religious conflict between Protestants and Catholics in the Holy Roman Empire.
During what years was the thirty year war?
A:
1618–1648