A period of relative stability has put the Iranian capital No1 on the list of world cities that have achieved biggest improvements in liveability over the past five years, as calculated by the Economist Intelligence Unit. The “most improved” top 10 contains some unexpected names. So, eg, the fourth place: Abidjan, Ivory Coast. Latest ranking: 128; Ranking five years ago: 131; Five-year index movement: 3.8%. Here: A supporter of Ivory Coast president Alassane Ouattara campaigns in a market in the city’s Koumassi quarter. (Photo by Sia Kambou/AFP Photo)

A view of sunken tank which promotes scuba diving tourism with its location at an artificial reef of Guvercin Island region of Kas district of Antalya, Turkiye on December 04, 2022. The sunken tank, situated at a depth of around 15 meters, is visible to both seasoned divers and those undergoing basic diving training. (Photo by Mahmut Serdar Alakus/Anadolu Agency via Getty Images)

“Contrails (short for “condensation trails”) or vapour trails are artificial clouds that are the visible trails of condensed water vapour made by the exhaust of aircraft engines. As the hot exhaust gases cool in the surrounding air they may precipitate a cloud of microscopic water droplets or, if the air is cold enough, tiny ice crystals”. – Wikipedia

Photo: An airplane leaves a vapor trail as it flies in front of he moon on January 17, 2007 above Hanover, Germany. (Photo by Alexander Hassenstein/Getty Images)

Valentyna Konstantynovska, 79 years-old, holds a weapon during basic combat training for civilians, organized by the Special Forces Unit Azov, of Ukraine's National Guard, in Mariupol, Donetsk region, eastern Ukraine, Sunday, February 13, 2022. The United States is evacuating almost all of the staff from its embassy in Kyiv as Western intelligence officials warn that a Russian invasion of Ukraine is increasingly imminent. (Photo by Vadim Ghirda/AP Photo)

A boy plays with a dragon-shaped puppet as he walks with his parent at Sydney CBD ahead of the Lunar New Year on February 09, 2024 in Sydney, Australia. Lunar New Year, also known as Chinese New Year, is celebrated around the world, and the Year of the Wood Dragon in 2024 is associated with growth, progress, and abundance, as wood represents vitality and creativity, while the dragon symbolizes success, intelligence, and honor. (Photo by Roni Bintang/Getty Images)

An injured fan is helped by a riot policeman during clashes between Red Star Belgrade and Partizan Belgrade fans in the stadium before the teams' Serbian Superliga soccer match in Belgrade, April 25, 2015. Serbian league leaders Partizan Belgrade held champions and bitter city foes Red Star to a 0-0 draw in a derby match marred by bad crowd trouble before kickoff on Saturday. The start was delayed for 45 minutes after home Red Star supporters pelted riot police with seats and flares, forcing officers to retreat from the north tier that houses the club's diehard fans. (Photo by Marko Djurica/Reuters)

Afghan police officers secure a transportation headquarters that was besieged for two days last weekend, on May 14, 2011 in Kandahar, Afghanistan. Taliban gunmen and suicide bombers unleashed a major assault May 7, 2011 on locations in Kandahar that included the governor's compound, the mayor's office, police stations, and an intelligence agency headquarters. (Photo by Majid Saeedi/Getty Images)

For our latest mission, we put a Carnegie Hall orchestra in the middle of New York City and placed an empty podium in front of the musicians with a sign that read, “Conduct Us.” Random New Yorkers who accepted the challenge were given the opportunity to conduct this world-class orchestra. The orchestra responded to the conductors, altering their tempo and performance accordingly. This project was a collaboration with Carnegie Hall and Ensemble ACJW.