In this Wednesday, December 2, 2015 photo, Dr. Gal Kelmer, head of the department of large animals, unties a horse after its operation at the University's Koret School of Veterinary Medicine in Rishon Lezion, Israel. “Horses have an instinctive response of flight from danger”, Kelmer said. “The minute they wake up they start trying to stand and run, even if they don't have control of their limbs. So then they fall”. (Photo by Oded Balilty/AP Photo)

In this December 22, 2015, photo, Rayani Air flight crews prays before departure at Kuala Lumpur International Airport 2 in Sepang, Malaysia. Malaysia's Rayani Air took to the skies over the weekend with a clear bailiwick. It is the country's first Islamic airline, offering flights that adhere to Islamic rules including prayers, no-alcohol, no-pork meals, and a strict dress code for Muslim female flight attendants. (Photo by Joshua Paul/AP Photo)

In this October 15, 2014 file photo, Katsu Nakamura, sky division manager for Yamaha USA, moves the RMax unmanned helicopter into position before a demonstration of its aerial application capabilities at the University of California, Davis' Oakville Station test vineyard in Oakville, Calif. Researchers at UC Davis have been studying the effectiveness of the drone's ability for spraying pest control and nutritional materials on the test vineyard in California's Napa Valley. (Photo by Rich Pedroncelli/AP Photo)

This Thursday, January 22, 2015 photo made with a long exposure shows the glow from a Noctiluca scintillans algal bloom along the seashore in Hong Kong. The luminescence, also called Sea Sparkle, is triggered by farm pollution that can be devastating to marine life and local fisheries, according to University of Georgia oceanographer Samantha Joye. Noctiluca itself does not produce neurotoxins like other similar organisms do. But its role as both prey and predator tends can eventually magnify the accumulation of toxins in the food chain, according to R. Eugene Turner at Louisiana State University. (Photo by Kin Cheung/AP Photo)

In this Tuesday, March 17, 2015 photo, a French military plane takes off from the flight deck of the French Navy aircraft carrier Charles de Gaulle in the Persian Gulf. Aircraft aboard the French carrier are flying bombing and reconnaissance missions as part of a U.S.-led coalition targeting Islamic State militants in Iraq. (Photo by Hasan Jamali/AP Photo)

In this Saturday, May 7, 2016 photo, Afghan refugee Shazia Lutfi, 19, peeks through the door of her room at the former prison of De Koepel in Haarlem, Netherlands. The government has let Belgium and Norway put prisoners in its empty cells and now, amid the huge flow of migrants into Europe, several Dutch prisons have been temporarily pressed into service as asylum seeker centers. (Photo by Muhammed Muheisen/AP Photo)

In this October 21, 2015, file photo, a young man rides a hoverboard along a Manhattan street toward the Empire State Building in New York. More than 500,000 hoverboards are being recalled after reports that they can burst into flames. The Consumer Product Safety Commission said Wednesday, July 6, 2016, it has received 99 reports of battery packs in the two-wheel motorized scooters catching fire or exploding that causing burns or property damage. The recalled hoverboards were made by eight companies. (Photo by Kathy Willens/AP Photo)

In this Thursday, May 8, 2014 photo, Iranian coal miners push metal carts to be loaded with coal at a mine near the city of Zirab 212 kilometers (132 miles) northeast of the capital Tehran, on a mountain in Mazandaran province, Iran. International sanctions linked to the decade-long dispute over Iran's nuclear program have hindered the import of heavy machinery and modern technology in all sectors, and coal mining is no exception. (Photo by Ebrahim Noroozi/AP Photo)