PRESS DIGEST -Wall Street Journal - Dec 30

Dec 30 (Reuters) - The following are the top stories in the Wall Street Journal. Reuters has not verified these stories and does not vouch for their accuracy.

* The disappearance of AirAsia's Flight 8501 is the third aviation disaster this year to strike a region where air traffic has grown spectacularly to become the world's biggest market, posing new challenges to safety regulators, airlines and governments. (http://on.wsj.com/1EDtlHn)

* The Vermont Yankee nuclear plant ended more than four decades of electricity production on Monday, moving to full retirement amid growing competition from cheap natural gas from the shale boom. (http://on.wsj.com/13G6BFm)

* Chinese smartphone maker Xiaomi is now officially the world's most valuable tech startup, worth $46 billion-the exclamation point on a year of extraordinary valuations. (http://on.wsj.com/1JYVp8d)

* Pension funds, endowments and wealthy individuals that invest with private equity are finding it increasingly hard to get into the most sought-after funds, according to data and industry participants. (http://on.wsj.com/1twcIZn)

* New York-based Shake Shack Inc filed for an initial public offering Monday, the latest dining chain seeking to capitalize on healthy investor demand for companies that cater to consumers. Shake Shack filed to raise as much as $100 million, though that is a placeholder amount that could change. (http://on.wsj.com/1BklZCz) (Compiled by Aurindom Mukherjee in Bengaluru)