On Tuesday, the markets were mixed as President Trump said he was not pleased with the China trade talks, and suggested the summit with North Korea may be delayed past June.

Also, J.C. Penney (JCP) - Get J. C. Penney Company, Inc. Report  shares declined after CEO Marvin Ellison quit to join Lowe's Cos. (LOW) - Get Lowe's Companies, Inc. (LOW) Report , Facebook (FB) - Get Facebook, Inc. Class A Report  CEO Mark Zuckerberg testified before European Union lawmakers about the social media firm's data protection standards, and U.S. crude oil futures rose to the highest levels in more than three-and-a-half years, sending gas prices on a path to $3 a gallon just before the start of long Memorial Day weekend. 

Here are three top takes from the columnists of Real Money and Real Money Pro, our premium sites for Wall Street professionals and active investors: 

Jim Cramer: Oil's Rise Shouldn't Be a Surprise -- And Don't Look for It to Stop

TheStreet's Jim Cramer says, "People seem astonished that oil could hit fresh highs this morning, but it was all there, less than a month ago. It was all there in the Schlumberger (SLB) - Get Schlumberger NV Report  conference call when CEO Paal Kibsgaard, in what I regard as one of the more overlooked and dismissed statements, said that supply and demand were at last in balance, yet global crude stocks were well below their five-year average. That, he said, meant crude could start to move up smartly, given that demand was now running up 1.5 million barrels over last year. That's just what it has done."

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Start Your Engines, the Market Just Received Some Extremely Bullish Signals

"You might recall last Friday's Market Recon column. I explained to you there why I was turning a bit more bullish, at least in the short term. That was technical. Sure, Monday was about an apparent easing in the harsher direction that the U.S.-China trade relationship had been headed down, but the VWAP sellers failed to significantly dent the markets late in the game. I think the sustainability of the day's rally was really a product of the confidence shown by two key players in this U.S. administration," notes Real Money columnist Stephen Guilfoyle.

3 of My Favorite Medical Diagnostic Plays

"It is nice to see the small cap benchmark, The Russell 2000 hit new all-times and 'catch up' to its larger brethren recently. Given this, I thought we would provide some updates on three of my favorite medical diagnostic concerns in the market," writes Real Money Pro columnist Bret Jensen. "In April, I was considering calling three testing plays my 'Devil's Portfolio' given they were all selling almost exactly at $6.00 a share at the time. Fortunately, these equities have been in rally mode since then."