Apple is to open a research lab in the southern Chinese city of Shenzhen, its chief executive Tim Cook said on Wednesday, as it seeks to boost sales and improve its relationship with domestic authorities. News of the center, which will be Apple’s second in China after a new facility in Beijing, comes as the government is pressing foreign technology groups to carry out more high-end work on the mainland, to boost the local industry. For the US technology company, a closer relationship with the Chinese authorities has been a priority following a number of setbacks this year. These have ranged from a copyright infringement lawsuit in which a Chinese company alleged it owned the iPhone trademark, to a block on Apple’s iTunes video service, according to the Financial Times.