From the Wires

Twitter tests 'Buy' button feature

NYT: The social media network is publicly testing a "buy" button embedded in posts to allow users to instantly purchase products.

Organic brand Annie's sold to General Mills

Forbes: The specialty food maker was purchased by giant General Mills for $820 million.

U.S. to allow pharmacies to take back unused prescription drugs

WSJ: In an effort to get addictive painkillers off the street, federal authorities will allow pharmacies and clinics to take back unused prescription drugs from patients.

Chick-fil-A founder dies at the age of 93

Businessweek: Samuel Truett Cathy, founder of the Atlanta-based chicken restaurant chain, passed away this morning.

Starbucks to test express stores, tasting rooms

Fortune: The coffee giant is experimenting with new retail formats, including small locations and tasting rooms.

Comedienne Joan Rivers dead at 81

NYT: Joan Rivers was one of America's first successful female stand-up comics.

U.S. productivity rises 2.3% in Q2

WSJ: Nonfarm labor productivity, or output per hour worked, rose at a 2.3% annual rate from April through June.

Obesity rates reach historic highs in U.S. states

Reuters: Adult obesity rates increased in six U.S. states and decreased in none last year.

CVS stores go tobacco-free

New York Times: All 7,700 CVS locations nationwide no longer sell tobacco products; the company has rebranded itself as CVS Health.

Brain can be 'trained' to prefer healthy food

BBC: A study in the United States suggests the brain can be trained to prefer healthy food over unhealthy high-calorie foods using a diet that does not leave people hungry.

Halliburton to pay $1.1B to settle lawsuits

Bloomberg: Halliburton Co. agreed to pay $1.1 billion to settle a number of oil spill lawsuits.

U.S. eating habits improve, except among poor

WSJ: A 12-year study found that American eating habits have improved, except among low-income adults.

Google tests drone deliveries

BBC: Google has built and tested autonomous aerial vehicles through Project Wing.