• Gary Becker, a University of Chicago professor who received the Nobel Prize in economic sciences and is credited with pioneering the approach to economics as the study of human behavior, has died at age 83.
"I was interested in social problems but felt that economics had the tools by which to handle these long-term interests and social questions," Becker said when he became a Nobel Laureate in 1992.
Becker was cited for applying economic analysis to a wide range of human behavior and interactions. The economics and sociology professor studied issues such as marriage and divorce, crime and punishment, addiction and household decisions.
Becker's mentor was famed economist Milton Friedman. The school honored them in 2011 with The Becker Friedman Institute for Research in Economics and Becker was named chair of the institute.
University of Chicago President Robert Zimmerman said Becker will be remembered as one of the foremost economic scholars of the 20th century.
"He was intellectually fearless," Zimmer said.
• Dr. Andres Carrasco, an Argentine neuroscientist who challenged pesticide regulators to re-examine one of the world's most widely used weed killers, has died. He was 67.
Carrasco, a molecular biologist at the University of Buenos Aires and past-president of Argentina's CONICET science council, was a widely published expert in embryonic development whose work focused on how neurotransmitters affect genetic expression in vertebrates. But none of his research generated as much controversy as his 2010 study on glyphosate, which became a major public relations challenge for the St. Louis-based Monsanto Company.
Glyphosate is the key ingredient in Monsanto's Roundup brand of pesticides, which have combined with genetically modified "Roundup-Ready" plants to dramatically increase the spread of industrial agriculture around the world. The U.S. Environmental Protection Agency and other regulators have labeled it reasonably safe to use if applied properly. But few countries enforce pesticide rules as rigorously as the United States, and farming's spread has increasingly exposed people to glyphosate and other chemicals.
Carrasco, principal investigator at his university's Cellular Biology and Neuroscience Institute, said in 2013 that he had heard reports of increasing birth defects in farming communities after genetically modified crops were approved for use in Argentina, and so decided to test the impact of glyphosate on frog and chicken embryos in his laboratory.
His team's study, published in the peer-reviewed Chemical Research in Toxicology journal, found that injecting very low doses of glyphosate into embryos can change levels of retinoic acid, causing the same sort of spinal defects that doctors are increasingly registering in communities where farm chemicals are ubiquitous. Retinoic acid, a form of vitamin A, is fundamental for keeping cancers in check and triggering genetic expression, the process by which embryonic cells develop into organs and limbs.
"If it's possible to reproduce this in a laboratory, surely what is happening in the field is much worse," Carrasco told the AP. "And if it's much worse, and we suspect that it is, what we have to do is put this under a magnifying glass."
• Veteran actress, director and producer Nancy Malone has died at age 79 in Los Angeles.
She was a producer of the 1970s series "The Bionic Woman" and directed episodes of numerous TV shows, including "Melrose Place" and "Diagnosis Murder."
She starred in the groundbreaking 1950s series, "Naked City," and appeared in dozens of TV and film roles as well as on live radio.
• Harlan Mathews, who was appointed to the U.S. Senate seat vacated by Al Gore after he was elected vice president in 1992, died Friday. He was 87.
Lamar Alexander, a former two-term governor who succeeded Thompson in the Senate, said Mathews was a much loved figure in state government.
"Except for his great friend Ned McWherter, no one had more friends around the state Capitol than Harlan Mathews did," Alexander said. "He served our state and our country with distinction."
• Florida State officials say the composer of the music for the university's fight song has died. Tommie Wright was 95.
Wright joined the faculty as a music professor in 1949 and composed the music for the "FSU Fight Song" in 1950. He retired in 2008. Wright taught more than 58,000 students during his time at the university.
• Herb Lotman, the Philadelphia businessman who founded Keystone Foods and developed a mass- production system for making McDonald's Corp.'s frozen hamburgers, has died. He was 80.
Keystone Foods developed the first total distribution concept for McDonald's with the use of cryogenics and helped conceive the Chicken McNugget in the 1980s. Over a 40-year period, Lotman turned Keystone into a multinational operation with $5 billion in sales, earning a rating among Forbes magazine's list of America's largest private companies in 2010.
• Lee Marshall, one of the actors who supplied the booming voice of Tony the Tiger in commercials, has died. He was 64.
Marshall began voicing the Kellogg's Frosted Flakes mascot in 1999, filling in for the original actor, Thurl Ravenscroft.
• Colin Pillinger, an ebullient space scientist who captured the popular imagination with his failed attempt to land a British probe on Mars, has died. He was 70.
Pillinger, a professor of interplanetary science at the Open University, was the driving force behind the largely privately funded Beagle 2 space mission.
The tiny craft -- named for the ship that took naturalist Charles Darwin on his 19th-century voyage of discovery -- was supposed to land on Mars on Christmas Day in 2003 and search for signs of life. But contact with the probe was lost soon after it separated from its European Space Agency Mars Express mother ship on Dec. 19. An investigation found that it may have burned up in the planet's atmosphere.
• Canadian author Farley Mowat, a master storyteller and tireless defender of nature and wildlife, has died. He was 92.
Mowat wrote some 40 books, many based on his own adventures and travels. Among his best-known works are "Never Cry Wolf", a fictional narrative about Mowat living among wolves in sub-arctic Canada, "Lost in the Barrens", which follows a Cree Indian boy and a Canadian orphan's adventures in the Arctic. He said he was lucky to be able to combine his two passions: writing and nature, calling the latter "the only subject I really want to write about."
Acclaimed Canadian novelist Margaret Atwood tweeted that Mowat was a "wonderful colleague & friend of many years."
• Famed research test pilot Bill Dana, who flew the X-15 rocket plane and other pioneering aircraft during the birth of the space age, has died at age 83.
Starting in the 1950s, Dana logged more than 8,000 hours in more than 60 types of aircraft, ranging from helicopters and sailplanes to the hypersonic X-15, which he flew to a maximum altitude of nearly 59 miles, reaching a top speed of 3,897 mph.
In 2005, he was awarded civilian astronaut wings for two of those flights to the edge of space -- nearly 40 years after his X-15 flights -- because at the time, NASA did not confer astronaut wings on its pilots.
Dana also flew NASA's so-called lifting body aircraft that led to the design of the space shuttle.
• Arthur Oakes, a South Dakota man who drew national attention in the mid-1990s when he paid to keep the lights on at Mount Rushmore National Memorial during a federal government shutdown, has died at 74.
Oakes wrote a check for $240 in late 1995 to keep the stone-carved faces of George Washington, Abraham Lincoln, Thomas Jefferson and Theodore Roosevelt illuminated for a week.
• Sheikh Muhammad Nazim Adil al-Qubrusi al-Haqqani, a leading figure of Sufism, the mystical branch of the Islamic faith, has died at the age of 92.
Imam Shakir Alemdar, the vice grand mufti of Cyprus, confirmed the death. The imam hailed the Cypriot-born Sheikh Nazim as one of the world's great Islamic scholars and a spiritual leader to followers of Sufism, which traces its origins to the roots of Islam itself about 1,500 years ago.
• Jimmy Ellis, a heavyweight champion who sparred with an up-and-coming Muhammad Ali and later fought some of the era's best boxers, has died. He was 74.
Ellis, the son of a preacher who loved singing gospel music, held the WBA heavyweight title from 1968 to 1970. He lost to Joe Frazier in a fight to unify the world heavyweight championship in 1970. In 1971, Ellis was stopped by Ali in the 12th round. He retired in 1975.
Ellis defeated Jerry Quarry to win the WBA crown in 1968.
• Cornelius Gurlitt's long-secret hoard of 1,280 major artworks set off an international uproar last year over the fate of art looted by the Nazis. Now his death has triggered a new round of speculation over who will eventually own his unparalleled collection.
A spokesman for the reclusive German collector, who died at age 81 at his apartment in Munich, said Gurlitt had living relatives but he would not say who they are.
Gurlitt was thrust into the public spotlight in November when authorities, following a report by German magazine Focus, disclosed that they had seized 1,280 works by artists including Pablo Picasso, Henri Matisse and Marc Chagall from his Munich apartment more than a year earlier.
Some of the pieces -- by Matisse, Chagall and Otto Dix -- were previously unknown, not listed in the detailed inventories compiled by art scholars.
Gurlitt had inherited the collection of paintings, prints, drawings and sculptures from his father, Hildebrand Gurlitt, an art dealer who traded in works confiscated by the Nazis and who died in 1956.
• From the time he was first arrested, at the age of 14, for fishing near his home, Billy Frank Jr. had been a fierce and tireless champion for salmon, tribal sovereignty and the right of Northwest tribes to fish in their traditional waters.
Nearly 70 years of advocacy ended when the Nisqually tribal elder died at his home near Olympia. He was 83.
Frank figured prominently in Northwest fish-in demonstrations of the 1960s and 1970s that eventually led to sweeping changes in how salmon and other fish are managed in Washington state.
He was arrested more than 50 times for "illegal fishing" during the protests that came to be known as the fish wars. Patterned after the sit-ins of the civil rights movement, the campaign was part of larger nationwide movement in the 1960s for American Indian rights.
• Elena Baltacha, a former top-50 professional tennis player who had been fighting liver cancer since retiring from the game, has died. She was 30.
The former British No. 1 died peacefully surrounded by family and friends, the Women's Tennis Association said on its website. The Kiev-born Baltacha, who represented Britain at the 2012 London Olympics, was diagnosed with the illness in January, two months after retiring from tennis and only weeks after she married her long-time coach Nino Severino.
• Former U.S. Rep. Jim Oberstar, who represented northeastern Minnesota for 36 years and brought millions of dollars to the state as chair of the powerful House Transportation Committee, has died at 79.
Oberstar, a Democrat, was elected to Congress in 1974 and served 18 terms -- the state's longest-serving member of Congress. Oberstar became chairman of the House Transportation and Infrastructure Committee in 2006.
He was a champion for transportation safety and infrastructure improvements and supported the concept of intermodality -- connecting highways, subways, city buses, intercity rail and bike paths. He also brought jobs to his district, noting that the economic stimulus brought $212 million to St. Louis County alone and increased demand for iron ore from the Iron Range's taconite mines.
Associated Press writer Brian Bakst in St. Paul contributed to this report.