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March 1, 2019

Weekend reads: Doctors identify a 'third type of twinning': 'Semi-identical' twins

Daily Briefing


    Ben Palmer's reads

    'Hey hungry, I'm dad.' Is there something in the DNA of older men that causes them to frequently use corny one-line "dad jokes?" According to Robert Pierce, a professor at the University Counseling Center at the University of Rochester, probably not—however, he believes that dads want to connect in ways that can't be misconstrued with their kids. "Dad jokes tend to be calming, not angry, and are simple enough that anyone, even a little kid can get them," he said. He added that dads "don't want to tell dirty stories" but rather they just want "to be a good dad. And one way to be approachable and fun is to tell goofy puns or one-liners." Even if the joke ends in an eye roll, "that's all part of the game, the family inside joke," Pierce said.

    Laws that ban trans fats may be good for your heart. After New York City in 2006 restricted the amount of trans fats used in restaurant food, the heart health of New Yorkers who dined out improved, according to an analysis in the American Journal of Public Health. For the analysis, researchers assessed more than 200 randomly selected blood specimens drawn in 2004 and 2014 from participants in a broader health study. The researchers found that, after the trans fat restrictions in New York took effect, New Yorkers who ate out at least four times a week experienced a 61% drop in trans fatty acid levels in their blood.

    Danielle Poindexter's reads

    A 'third type of twinning.' Doctors in Australia have identified a second case of "semi-identical twins" created from one egg and two sperm. The doctors originally assumed the twins were identical, since an early ultrasound showed that both shared the same placenta. However, during a follow-up ultrasound later in the pregnancy the team realized something special happened: one of the babies was male and the other was female—something that is impossible for identical twins. The doctors later found out that the mother's DNA was identical in both babies, but the father's DNA varied. The case confirms that there is a "third type of twinning," according to Michael Gabbett of Queensland University of Technology in Brisbane, although it appears to be exceptionally rare: The only other reported case of semi-identical twins occurred in 2007 (Emery, Reuters, 2/27).

    Tracking technology might tell you the life story of your chicken sandwich. Companies are looking into putting tracking devices on chickens so that consumers "will know every step that chicken has taken," according to Robyn Metcalfe, a food historian at the University of Texas at Austin. One company, ZhongAn Online, has already fitted over 100,000 chickens with GPS trackers that track how much exercise the chickens get and what they eat. The company is also developing facial-recognition technology that will help consumers confirm that the organic chicken they're eating is, in fact, the one they pointed out on a farm one day. According to Metcalfe, the technology can help the industrial sector "lower risk" and prevent recalls by acting as another way to confirm that the food came from a safe place.

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