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Timing is everything. Especially in a homicide investigation.
But the time of death after 36 hours can be difficult to pin down, owing to decomposition and other limiting physical factors. Now scientists are trying to use science to attempt to give detectives more-detailed timelines in death investigations. One involves observing the breakdown in muscle proteins and enzymes – and the other potentially analyzes the color changes in dried bloodstains.
The muscle-protein method was developed by a group of researchers at the University of Salzburg, and announced today by the Society of Experimental Biology at its annual conference in Prague.
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By observing the breakdown in the proteins and enzymes in dead pigs, the scientists said they can get an estimated time of death accurate up to 240 hours. Other natural chemicals, including tropomyosin and acitinin, might provide an accurate timelines even beyond that window, they added.
“It is highly likely that all muscle proteins undergo detectable changes at a certain point in time, and this would extend the currently analyzed timeframe even further,” said Peter Steinbacher, the leader of the research team, adding that human biology appears to be very similar to that of pigs so far.
The other forensic technology which may eventually help detectives is a bit more conceptual. Light spectrometry on a smartphone is proposed in a pair of pieces in the journal Nature this week.
Though the color change of blood stains has been calculated for more than a century by criminal investigators, the results are so variable they don’t often stand up in court, according to the scientists. They can only provide an indefinite lead for detectives.
But a new and very-mobile form of advanced light spectrometry which uses suspensions of particles called colloidal quantum dots, which filter and analyze the wavelengths incoming light, according to the research, a collaborative work between the University of Beijing, the Massachusetts Institute of Technology, and the California Institute of Technology.
The results are potentially more scientifically exact — and a potential piece of evidence to bring against killers of the future, said a Nature editorial.
“These are selfies from the quantum world,” they wrote. “Beware would-be bloody criminals.”