The return of prominent Chinese scientists from the United States to their motherland is again in spotlight after a noted scientist announced that she would resign from her tenured professorship at a top U.S. university.

Noted structural biologist Yan Ning became the latest prominent addition to a growing list of Chinese scientists returning to China when she announced on Nov 1 that she would resign from her tenured professorship at Princeton University and return to China to help build the Shenzhen Medical Academy of Research and Translation.

Her announcement spread like wildfire on Chinese social media, attracting over 480 million views on the Chinese microblogging platform Sina Weibo. Many netizens called her a "goddess scientist" and wished her success in her new job.

Last year, over 1,400 U.S.-based ethnic Chinese scientists switched affiliation from U.S. to Chinese institutions, according to a joint report by Harvard, Princeton and Massachusetts Institute of Technology academics.

Many of the scholars who returned had relinquished tenured positions at top U.S. universities, the report said. They worked in key disciplines, including physical and life sciences, engineering, mathematics and computer science.

A neuroscientist based in Anhui, Hefei province, who had served in senior positions at multiple U.S. institutions, said the U.S. has traditionally been a brain drain for Chinese scientists, but there has been a noticeable outflow of Chinese scientists leaving the U.S. to return to China in recent years.

"This is the result of China's rising recognition and support for quality talents on the one hand, and the U.S. prosecution and underutilization of Chinese researchers on the other," the scientist said on condition of anonymity for fear of being targeted by the U.S. government.

In late September, the U.S. Department of Justice accused mathematician Xiao Mingqing, chemist Franklin Tao and materials scientist Cheng Zhengdong of undermining U.S. national security and defrauding the U.S. government by purposefully hiding their ties to Chinese institutions, according to the journal Science.

However, courts in the U.S. states of Illinois, Kansas and Texas either threw out the most severe charges or gave relatively lenient sentences for lesser offenses. Tao was able to overturn his conviction, Cheng accepted a plea deal and Xiao was sentenced to probation instead of prison.

Analysts said the three scientists' ordeals proved that U.S. Department of Justice's now-defunct "China Initiative", which disproportionally targeted ethnic Chinese scientists, is legally questionable. The program, launched in 2018, has also had a "chilling effect" on the Chinese scientific community in the U.S., according to the advocacy group Asian American Scholar Forum.

A medical professor in Wenzhou, Zhejiang province, who had worked in the U.S. for over two decades, said that some of the alluring factors that drew Chinese scientists home are opportunities and resources, stable employment, high social status, cultural and familial ties, and the belief that China is rising as a global science and technology powerhouse.

The professor said that Chinese scientists are being "pushed out of the U.S." because of heightened political tension between the two countries, fear of being wrongly accused and prosecuted, increased difficulty in securing grants due to their China ties, and racial discrimination in career advancement and society, especially during the COVID-19 pandemic.

"U.S. federal research grants now require scientists to disclose their connections to China when applying. If scientists were to hide their ties, then they could be in deep trouble," the expert said. "Given how extremely competitive grant applications are in the U.S., if scientists were to report their Chinese ties, they would likely get passed over.

"Grants are the lifeblood of scientists. Without it, there will be no academic output and career progression. For U.S.-based scientists with ties or collaborations in China, this puts them in a challenging situation."

The professor said the outflow of U.S.-based ethnic Chinese scientists will likely continue if China adheres to opening-up and being supportive of the influx of new talents by giving them the resources, freedom and time to succeed in a new research environment.

Paul Yan, a graduate of the University of California, San Diego, returned to China early this year after graduating in December because, as he said, "there are more opportunities in China".

"In China, new big things emerge every two to three years. But in the U.S., it's rather difficult for the Chinese to achieve the same thing."

Christopher S. Tang, chair in business administration at the UCLA Anderson School of Management, wrote in a recent article that Asian American professionals and scientists, including Chinese Americans, remain underrepresented in leadership roles and are regularly left out of discussions about discrimination in the workplace.

"This climate makes many Chinese scientists and professionals pessimistic about their prospects in the United States. They may, however, be more optimistic about China, when Chinese universities and companies are offering them senior positions with attractive benefits," he said.