A truffle is seen on a table in Alba, north-western Italy November 11, 2013. Located in the heart of the Langhe – the hilly southern area of Italy's northwestern Piedmont region – Alba is the country's capital of white truffles, a variety of the prized fungus which grows underground. Truffles are found two to eight inches (5-20cm) below the ground near the roots of trees. They give off an odour which lasts for a limited period of time and can be detected with the assistance of well-trained dogs and experienced hunters. Output of white truffles, which are not cultivated and only grow naturally in forests, has fallen in Italy over the past few years, largely because climate change has brought a damaging mix of drought and torrential rains. (Photo by Stefano Rellandini/Reuters)

A couple passes the sculpture “Transformer” by Chinese artist Bi Heng during snowfall in Kassel, central Germany, Tuesday March 12, 2013. Frankfurt airport closed, a quarter of flights out of Paris were canceled, Belgium suffered record traffic jams and high-speed trains were stuck in stations – all because of a sudden dump of oddly late snowfall on Western Europe. Less prepared for the kind of heavy snow that regularly hits northern and eastern neighbors, France, Britain and Belgium struggled Tuesday to keep moving amid the frosty, blustery conditions. (Photo by Uwe Zucchi/AP Photo/Dpa)

A tear rolls down the cheek of Karima el-Mahroug, also known as Ruby, a Moroccan woman at the center of ex-Premier Silvio Berlusconi's s*x-for-hire trial, as she reads a statement to reporters during a protest outside the court house, in Milan, Italy, Thursday, April 4, 2013. The Moroccan woman at the center of ex-Premier Silvio Berlusconi's s*x-for-hire trial has denounced what she says is psychological warfare being waged against her by Italian prosecutors. Ruby, read out a lengthy statement Thursday to a gaggle of reporters in front of Milan's courthouse denying she was a prostitute and insisting that prosecutors hear her side of the story. (Photo by Luca Bruno/AP Photo)

The main church in the town of San Damian Texoloc, Mexico stands in front of the Popocatepetl volcano as is spews ash and vapor early Tuesday, July 9, 2013. Last Saturday, Mexico's National Center for Disaster Prevention raised the volcano alert from Stage 2 Yellow to Stage 3 Yellow, the final step before a Red alert, when possible evacuations could be ordered after the Popocatepetl volcano spit out a cloud of ash and vapor 2 miles (3 kilometers) high over several days of eruptions. (Photo by J. Guadalupe Perez/AP Photo)

In this Sunday, August 5, 2012 file photo South Africa's Oscar Pistorius starts in the men's semi-finals of the 400-meter in the Olympic Stadium at the 2012 Summer Olympics, London. Pistorius could be granted parole on Friday, Nov. 24, 2023 after nearly 10 years in prison for killing his girlfriend. The double-amputee Olympic runner was convicted of a charge comparable to third-degree murder for shooting Reeva Steenkamp in his home in 2013. He has been in prison since late 2014. (Photo by Anja Niedringhaus/AP Photo)

An armed man herds his cattle close to the village of Nimini in northern South Sudan, February 8, 2017. In the chaos of South Sudan's civil war, it took three years for Nyagonga Machul to find her lost children. Machul had traveled from her village to the capital when President Salva Kiir, an ethnic Dinka, fired his deputy Riek Machar, a Nuer, in 2013. (Photo by Siegfried Modola/Reuters)

The antennas of the European Southern Observatory's Atacama Large Millimeter/Submillimeter Array, also known as ALMA, are set against the splendor of the Milky Way in this picture by Babak Tafreshi. Construction of the full ALMA array is due to be completed in Chile's Atacama Desert in 2013, but the facility is already making scientific observations with a partial array of antennas. (Photo by ESO/B. Tafreshi/TWAN)