A database of mass killings from 2006 to 2023 maintained by the Associated Press, USA Today and Northeastern University shows that about only 7 percent of shooters are over the age of 50, while more than 20 percent of victims are 50 or older.

Power plants aren’t built for extremes, said Matt Eckelman, an associate professor of civil and environmental engineering at Northeastern University. They operate best in the middle of the temperature range for which they were designed.

Neil Maniar, a professor of public health practice at Northeastern University in Boston, thinks that’s a good idea. Many Americans have skipped boosters because they were unsure whether they were eligible. A simplified schedule, he said, “will increase vaccination rates because it will hopefully make it easier for people to follow.”

“We don’t see many 60- and 70-year-olds committing mass homicides, and when they do it’s usually a murder-suicide within a family,” said Jack McDevitt, a criminologist at Northeastern University in Boston.

A database of mass killings from 2006 to 2023 maintained by the Associated Press, USA Today and Northeastern University shows that about only 7 percent of shooters are over the age of 50, while more than 20 percent of victims are 50 or older.

The new year has brought six mass killings in the U.S. in fewer than three weeks, accounting for 39 deaths. Three have occurred in California since Jan. 16, according to a database compiled by The Associated Press, USA Today and Northeastern University. 

Alan Clayton-Matthews, an economist and Northeastern University professor emeritus, meanwhile said he expects it could generate $528 million this fiscal year and another $1.1 billion in the next. He said ultimately expecting about $1.2 billion, on average, in revenue “seems reasonable.

The new year has brought six mass killings in the U.S. in fewer than three weeks, accounting for 39 deaths. Three have occurred in California since Jan. 16, according to a database compiled by The Associated Press, USA Today and Northeastern University. 

The recent slayings moved California up five slots to 26th place on the number of fatal mass shootings per capita in the U.S. since 2006, according to a USA TODAY/AP/Northeastern University mass killing database. 

Tran is the second-oldest mass killer in the U.S. over the last nearly 20 years according to a database compiled by The Associated Press, USA Today and Northeastern University. 

A team led by Mauricio Santillana, director of the Machine Intelligence Group for the Betterment of Health and the Environment at Northeastern University in Boston, shared plan for such a system last week in the journal Science Advances.

By that same date this year, six mass killings have claimed 39 lives, according to a database of mass killings maintained by The Associated Press, USA Today and Northeastern University.