Question: Sebastian Vettel and his Red Bull team have left their Formula One rivals trailing in their wake during a three-year domination of the sport. But ahead of the 2013 season getting underway in Australia later this month, it is the triple world champion and his all-conquering team which has some catching up to do after a preseason which has not gone entirely to plan. Red Bull, and every other team, was left in Mercedes' rear-view mirrors at the final preseason test in Barcelona last weekend, with Vettel failing to top the charts at any of the offseason practice. Vettel insists there is still time for Red Bull to turn it around ahead of 2013's curtain raiser on March 17, when he will begin his bid to become only the third driver to win four consecutive championships. "I would have loved to work more on the set-up, but I don't think that this is only me. I think everybody struggled in that area," the 25-year-old told Formula One's official website. "We cannot be satisfied with the state of affairs right now ... there is still time before Melbourne to make some significant changes." Vettel has been left frustrated by the tires introduced by the sport's official supplier Pirelli, which are softer than in 2012. Pirelli claim the new tires will speed up races and promote overtaking. "It is extremely difficult to pinpoint any exact area we are not satisfied with because the tires are not consistent enough," continued Vettel. "We need to have a good look at the data between now and Melbourne to have a better understanding of what to expect in Australia and the first few races of the season. In my opinion, lap times didn't matter all through the winter tests." Regardless of preseason statistics, Vettel will be the man every driver on the grid will be targeting when the lights go out at Melbourne's Albert Park. "I would say that we never had a winter that was less conclusive than this one: the tires last more or less, depending on how much temperature you are able to create," added Vettel. "So I think it is impossible for all of us to read the pace of the cars and to make out any favorites." Vettel will now head back to the team's British base in Milton Keynes before taking some time out ahead of the start of the campaign. "Immediately into the simulator!" said Vettel when asked what was next on his agenda. "To continue where we left business on Sunday. "We will then sit down and filter and interpret all the data that we have collected over the testing period to see what we can read out of it. "Finally, before heading to Melbourne I will allow myself some final quiet days before the season starts with all its force." Vettel made a slow start to the 2012 as there were eight different winners in the first eight races, but a run of four straight victories in the autumn set him on the way to his title triple, while Red Bull retained the constructors' title.
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Important parts: Sebastian Vettel not satisfied with Red Bull's preseason testing. The German has not topped the time sheets at any of the testing events. The Red Bull driver is the youngest triple world champion in Formula One history. The 2013 Formula One season begins with the Australian Grand Prix on March 17.

Question: The man who accepted three uncut diamonds from supermodel Naomi Campbell and held them privately for years is stepping down as a trustee of the Nelson Mandela Children's Fund, the fund said. Jeremy Ractliffe will not run for reelection as a trustee at the end of this month, the fund said Wednesday. He is also resigning immediately as a board member with the U.S. affiliate of the fund, it said. Ractliffe came under international scrutiny in early August when Campbell testified at the trial of former Liberian President Charles Taylor. She was asked about reports that Taylor gave her uncut diamonds in 1997, a story that prosecutors hoped to use as evidence to prove Taylor used "blood diamonds" to fund a brutal civil war in Sierra Leone. While Campbell said she didn't know whether Taylor was the source of the diamonds, she testified she gave them the next day to Ractliffe, a friend who at the time was the head of the children's fund. Ractliffe said in a statement afterwards that he kept the diamonds to protect the reputations of both Campbell and the charity. He handed the diamonds over to South African police after Campbell's testimony. "Mr. Ractliffe regrets his omission to inform the chairperson, CEO, and the rest of the board of trustees of the NMCF of his receipt of the uncut diamonds until now and acknowledges that had he done so, he and the board could have found a better and lawful way to manage the situation," the fund said in the statement. "He has apologised to the chairperson, CEO, the board, and the NMCF for the anxiety and possible reputational risk his conduct may have caused to the NMCF." Under South African law, the possession of uncut or rough diamonds is restricted to permit-holding producers, cutters, and toolmakers. Any other person who finds or receives unpolished diamonds is required to take them to a police station immediately. "Mr. Ractliffe has stated that he acted in what he sincerely believed to be in the best interest of the NMCF and its founder and realizes that he has left himself open to possible prosecution," the fund said in its statement. "For these reasons, he considers it correct and proper for him not to make himself available for reelection as a trustee." Conflict or "blood" diamonds are diamonds that are illegally traded to fund conflict in war-torn areas, particularly in central and western Africa, according to the World Diamond Council, which represents the commercial diamond trade. The United Nations defines conflict diamonds as "diamonds that originate from areas controlled by forces or factions opposed to legitimate and internationally recognized governments, and are used to fund military action in opposition to those governments, or in contravention of the decisions of the Security Council." They are generally in rough form, meaning they have recently been extracted from the earth and not yet cut. At the height of the civil war in Sierra Leone, it is estimated that conflict diamonds represented approximately four percent of the world's diamond production.
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Important parts:
Jeremy Ractliffe held on to diamonds given to him by Naomi Campbell. The diamonds allegedly came from former Liberian President Charles Taylor. He handed the diamonds to police earlier this month.