A general view of the Burj Khalifa on February 23, 2012 in Dubai, United Arab Emirates. At 829.84 m (2723 ft) tall the Burj Khalifa is currently the tallest building in the world. (Photo by Chris Jackson/Getty Images)

Ban Gioc – Detian Falls are two waterfalls on the Quây Sơn River, in Chinese Guichun River, straddling the Sino-Vietnamese border, located in the Karst hills of Daxin County, Guangxi (Chinese side), and in Trùng Khánh District, Cao Bằng province on the Vietnamese side, 272 km (169 mi) north of Hanoi. In Vietnamese, the two falls are considered as two parts of one waterfall with the sole name Bản Giốc. The two parts are called as: thác chính (Main waterfall) and thác phụ (Subordinate waterfall). Chinese texts sometimes name both falls from the Détiān falls on the Chinese side. During the summer rains the two waterfalls may join together.

Russian oppostion activists take part in a rally and march to Bolotnaya Square on February 4, 2012 in Moscow, Russia. Demonstrators braved temperatures as low as -20 degrees celsius as they took to the streets exactly one month before the presidential elections in protest against Vladimir Putin's efforts to return to the Kremlin for an unprecedented third term as President. (Photo by: Ilya Varlamov; Source: LiveJournal)

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Lake Natron is a salt lake located in northern Tanzania, close to the Kenyan border, in the eastern branch of the East African Rift. The lake is fed by the Southern Ewaso Ng'iro River and also by mineral-rich hot springs. It is quite shallow, less than three meters (10 feet) deep, and varies in width depending on its water level, which changes due to high levels of evaporation, leaving concentrations of salt and other minerals, notably sodium carbonate (natron).

The 37-year-old French artist Anne-Catherine Becker Echivard’s latest artworks were inspired by the silent movies of Charlie Chaplin and Buster Keaton; she uses real-life smelly fish heads as her models for some photos that depict everyday life to address topics.