The state fire marshal's office had previously ruled out four potential causes: weather, natural causes, anhydrous ammonium and ammonium nitrate in a rail car.

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On Monday, the state fire marshal's office said it ruled out four potential causes: weather, natural causes, anhydrous ammonium, and ammonium nitrate in a rail car.

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With only three or four potential causes still not ruled out, it is possible the National Transportation Safety Board will never issue a definitive judgment on what went wrong.

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Dunkley claims Mr Cummins died of natural causes but has admitted four charges of fraud relating to using his credit cards, as well as cashing cheques from a trust fund.

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Although he and his colleagues propose that bowel disease causes autism, in four of his 12 cases the children's behavioural problems preceded their bowel disease, an observation that clearly contradicts the hypothesis.

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Dunkley claims Mr Cummins died of natural causes and has also admitted four charges of fraud relating to using Mr Cummins' credit cards and cashing cheques from a trust fund days after he died.

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Mr Zarb arrived in 1997 to clean up a trading scandal and departed four years later with a multi-million-dollar severance package dripping with perks and a reputation that causes his name to pop up every time a senior economic position in government becomes available.

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With four regular employees, only two of whom are full time, VeryNice has limited resources to move the needle on causes.

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