Question: "What is the goal of electrons and holes moving into the quantum dot layer?" Context: "The structure of QD-LEDs used for the electrical-excitation scheme is similar to basic design of OLEDs. A layer of quantum dots is sandwiched between layers of electron-transporting and hole-transporting materials. An applied electric field causes electrons and holes to move into the quantum dot layer and recombine forming an exciton that excites a QD. This scheme is commonly studied for quantum dot display. The tunability of emission wavelengths and narrow bandwidth is also beneficial as excitation sources for fluorescence imaging. Fluorescence near-field scanning optical microscopy (NSOM) utilizing an integrated QD-LED has been demonstrated." Answer:
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Answer: excites a QD

Question: "Ministers without portfolio can get one from the?" Context: "The Government of Estonia (Estonian: Vabariigi Valitsus) or the executive branch is formed by the Prime Minister of Estonia, nominated by the president and approved by the parliament. The government exercises executive power pursuant to the Constitution of Estonia and the laws of the Republic of Estonia and consists of twelve ministers, including the Prime Minister. The Prime Minister also has the right to appoint other ministers and assign them a subject to deal with. These are ministers without portfolio they don't have a ministry to control." Answer:
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Answer: Prime Minister

Question: "The company is served by how many in the primary location?" Context: "RIBA Enterprises is the commercial arm of RIBA, with a registered office in Newcastle upon Tyne, a base at 15 Bonhill Street in London, and an office in Newark. It employs over 250 staff, approximately 180 of whom are based in Newcastle." Answer:
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Answer:
approximately 180