percier and fontaine were also responsible for much of the replanning of paris. they made a triumphal east-west route across the city. another roman touch was la rue de rivoli. they prepared designs for linking the tuileries gardens with the louvre and started on the interior of the museum itself, where their inventive details can be admired today. the newly constituted louvre became napoleon's domain. he commissioned france's finest artists to glorify his deeds. the most celebrated was jacques louis david. disappointed with the aftermath of the revolution, david had sworn never to trust in men again-- only in ideas, yet he was fascinated by napoleon and quickly succumbed to his spell. when he first met the young general, he said, "oh, my friends, "what a beautiful head he has. "it is pure. it is great. "it is as beautiful as the antique. yes. bonaparte is my hero." decades before the revolution, the encyclopedist diderot had suggested the louvre be used for the public display of the royal collections. afterwards, in 1793, it opened as the museum central des arts

when 29-year-old jennifer fontaine was pregnant last year a standard blood screen suggested her babyre genetic defect. >> it was very devastating that the baby might not make it through the birth as the baby might be stillborn or if she does, she may not live up to her first birthday. >> but that standard blood test isn't definitive. so fontaine was given the option of either an amniocentesis, an invasive test that carries a 1 in 600 chance of miscarriage. she opted for the blood test. after worrying for more than two weeks, she got good news. there was no defect. >> it was the best feeling ever to know that everything was fine and in a few months we were going to have a perfect baby girl, so we were happy. >> since 2011 the fetal blood test was used to screen high risk pregnant women. researchers wanted to find out if this dna test could be used for low risk women as well. they looked at samples from 1,900 women and found for down syndrome, the standard screening hat a 3.6% false positive rate compared to 0.3%. >> far fewer women are made anxious and need to go on for the further co