Business

Equipment upgrades, fleet failures and tuck-in acquisitions have created an inventory of used mobile communications units, and bargain-seeking carriers looking for small batches of these systems have created sustainable demand for secondhand units, several tech executives have said.

The average cost of a gallon of U.S. retail diesel declined 4.3 cents to $4.061 a gallon last week, the biggest drop in nearly a year, according to the Department of Energy.

Transportation software maker TMW Systems said that it has acquired privately held Appian Logistics Software. Terms were not disclosed.

Menlo Worldwide Logistics said it is expanding manufacturing for Bobcat Co. and will be hiring about 35 workers in the next few weeks.

A new study has concluded that Boston should ban the transport of nearly all nonradioactive hazardous materials through the downtown and North End areas to protect the public.

Canadian transporter TransForce Inc. said its first-quarter net earnings fell to C$14.9 million, or 15 Canadian cents a share, from C$26.1 million, or 27 cents, in a year earlier.

Existing home sales fell 0.8% in April, the National Association of Realtors said Thursday.

Manufacturing activity in the Philadelphia region slowed in May, the Federal Reserve Bank of Philadelphia said Thursday.

An index of leading economic indicators fell 0.3% in April after nine months of gains, the New York-based Conference Board said Thursday.