Global business

The Federal Reserve remains on course to raise interest rates this year, according to Janet Yellen, the central bank's chairwoman. She made the remarks in testimony to Congress, pointing out that an increasingly robust labor market and signs that inflation may be ticking up made a rate increase necessary, despite the Greek crisis and turbulence in China's stock markets. Yellen didn't say when rates would rise, but many investors are betting on September.

China's GDP grew 7 percent in the second quarter, which was higher than had been expected. Some questioned the veracity of the 7 percent figure, which matches the government's official growth target.

Reports emerged that Tsinghua Unigroup, a state-owned Chinese firm, was planning to bid for Micron Technology, an American maker of memory chips. At $23 billion it would be by far the biggest takeover of an American company by a Chinese one, though any offer would run into stiff resistance in Congress, which views America's semiconductor business as a strategic asset.

Marathon Petroleum agreed to take over MarkWest Energy. The two U.S. firms valued the transaction at $20 billion, making it one of the biggest deals in the energy industry since last summer's slump in oil prices.

Lower oil prices helped Delta Air Lines boost its quarterly profit to $1.5 billion. The sharp reduction in fuel expenses offset its nearly $600 million in losses on fuel-price hedging.

Political economy

Nigeria's president, Muhammadu Buhari, sacked all of his senior military commanders after suffering setbacks in the fight against Boko Haram, a jihadist insurgency.

Colombia's president, Juan Manuel Santos, said the government would scale back attacks on the FARC, a left-wing guerrilla army, in response to the group's unilateral cease-fire. To speed up peace talks, which are taking place in Havana, Santos said negotiators would deal with all outstanding issues at once. He will review the talks in November.

Mexico opened its oil sector to private and foreign investment. But the first auctions of rights to explore 14 shallow-water blocks attracted few bids; only two contracts were awarded.

The lower house of Japan's parliament passed bills aimed at deepening its military alliance with America. Shinzo Abe, the prime minister, says the bills will help Japan shoulder its international defense obligations. The attempt to legislate for "collective defense" has united most constitutional scholars against his coalition government, however, and has triggered protests.

Narendra Modi, India's prime minister, met his Pakistani counterpart, Nawaz Sharif, at a summit of regional powers in Russia. Modi accepted an invitation to pay a visit to Pakistan next year, which will be the first by an Indian prime minister since 2004.