Tadao Ando, Elizabeth Diller, Rem Koolhaas and Thom Mayne are among the many signing a petition to urge Russian president Vladimir V. Putin to reconsider the fate of the neglected Shabolovka Radio Tower (Shukhov Tower), “a structure of dazzling brilliance and great historical importance,” as Norman Foster once described. Designed by Vladimir Shukhov and completed in 1922, the 160-meter hyperboloid structure is a 20th-century engineering feat that has served as a landmark of modernist architecture.