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A railway electrification system supplies electric power to railway trains and trams without an on-board prime mover or local fuel supply. Electrification has many advantages but requires significant capital expenditure. Selection of an electrification system is based on economics of energy supply, maintenance, and capital cost compared to the revenue obtained for freight and passenger traffic. Different systems are used for urban and intercity areas; some electric locomotives can switch to different supply voltages to allow flexibility in operation.
What is of the factors the capital cost of electrification system depends on?
A: maintenance

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In 525 BC, the powerful Achaemenid Persians, led by Cambyses II, began their conquest of Egypt, eventually capturing the pharaoh Psamtik III at the battle of Pelusium. Cambyses II then assumed the formal title of pharaoh, but ruled Egypt from his home of Susa in Persia (modern Iran), leaving Egypt under the control of a satrapy. The entire Twenty-seventh Dynasty of Egypt, from 525 BC to 402 BC, save for Petubastis III, was an entirely Persian ruled period, with the Achaemenid kings all being granted the title of pharaoh. A few temporarily successful revolts against the Persians marked the fifth century BC, but Egypt was never able to permanently overthrow the Persians.
What was the duration of the 27th dynasty of Egypt?
A: 525 BC to 402 BC,

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Although the Catholics and the Orthodox may honor and venerate Mary, they do not view her as divine, nor do they worship her. Roman Catholics view Mary as subordinate to Christ, but uniquely so, in that she is seen as above all other creatures. Similarly Theologian Sergei Bulgakov wrote that the Orthodox view Mary as "superior to all created beings" and "ceaselessly pray for her intercession". However, she is not considered a "substitute for the One Mediator" who is Christ. "Let Mary be in honor, but let worship be given to the Lord", he wrote. Similarly, Catholics do not worship Mary as a divine being, but rather "hyper-venerate" her. In Roman Catholic theology, the term hyperdulia is reserved for Marian veneration, latria for the worship of God, and dulia for the veneration of other saints and angels. The definition of the three level hierarchy of latria, hyperdulia and dulia goes back to the Second Council of Nicaea in 787.
Which theologian wrote that Mary is considered to be "superior to all created beings," but is not to be the object of worhip?
A: Sergei Bulgakov

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Early progress toward the development of vaccines occurred throughout this period, primarily in the form of academic and government-funded basic research directed toward the identification of the pathogens responsible for common communicable diseases. In 1885 Louis Pasteur and Pierre Paul Emile Roux created the first rabies vaccine. The first diphtheria vaccines were produced in 1914 from a mixture of diphtheria toxin and antitoxin (produced from the serum of an inoculated animal), but the safety of the inoculation was marginal and it was not widely used. The United States recorded 206,000 cases of diphtheria in 1921 resulting in 15,520 deaths. In 1923 parallel efforts by Gaston Ramon at the Pasteur Institute and Alexander Glenny at the Wellcome Research Laboratories (later part of GlaxoSmithKline) led to the discovery that a safer vaccine could be produced by treating diphtheria toxin with formaldehyde. In 1944, Maurice Hilleman of Squibb Pharmaceuticals developed the first vaccine against Japanese encephelitis. Hilleman would later move to Merck where he would play a key role in the development of vaccines against measles, mumps, chickenpox, rubella, hepatitis A, hepatitis B, and meningitis.
The rabies vaccine was created in what year?
A:
1885