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Forensic Science An area of science made hugely popular by television shows such as CSI and Crossing Jordan, forensics covers just about every aspect of science you can think about. Forensic scientists are use all kinds of tools in their work, like 3D models and lie detectors. Smart Moves has been speaking to a forensic scientist in WA called Shari. Shari's spends her days messing around with dead pigs. Or if you like bugs and creepy-crawlies, you might be interested in forensic entomology. Want to hear about how a simple database will help solve crimes across all Australian states and territories? Then check out Crimtrac There are a lot of other inventions that people are coming up with that will make solving crime a lot faster, including a product called Mycrolab and a system that will allow investigators to analyse DNA at crime scenes. Background Notes A brief synopsis of each of the forensic science items in our shows and links to our references.
There recently have been some great advancements in the world of virtual crime solving. Ok, so the crime fighting is real, it is just the methods that are computer generated. The advancements are to do with a little thing that we all take for granted - 3D vision. A company in Toronto, Canada called MDRobotics has developed a thing that they call the Instant Scene Modeller. It is a stereo-camera that can be used to record a crime scene. Then a 3D-reconstruction of it can be generated on a computer, and things can be measured and scenarios can be played out without actually tampering with the real crime scene. To top it all off, the Instant Scene Modeller can be taken into courtrooms and jurors can see the crime scene in 3D, rather than having to mentally fit photographs together. Another way of virtually fighting crime involves Virtopsy - a new process that has come out of Switzerland. Virtopsy enables the virtual analysis of victims of crime using MRI and CT scans, as well as other 3D imaging technologies. This way, doctors can examine victims without actually having to be in the same room as them. This is great for examining victims of contagious diseases or even just to collect evidence without changing anything. Finally, here in Australia we are also getting involved in the world of virtual crime-solving. Researchers from the University of Melbourne are working on some 3D technology that will help to more accurately identify bite marks in violent crime cases. The technique uses 3D animations of a suspect’s teeth biting a victim. The animations show the probably of a match between the bite mark and the teeth more accurately than current techniques. Reference
Return to top. In criminology lie detection is a crucial but tricky process. There is a need for more accurate ways to do this. One way that is showing a lot of promise is a method that monitors a person’s face using an infra-red camera. In the future this method may take the place of the traditional polygraph test. Currently, the polygraph is the widely used lie detector that is also often shown in movies. It measures a person’s physiological responses while being questioned. However, the technology isn’t perfect – innocent people can be so nervous that they appear guilty (if you had to have a heart rate monitor strapped around your chest, have your blood pressure monitored, and electrodes attached to your fingertips, wouldn’t you be nervous?), and practiced liars can fool the system by staying calm and controlling their breathing and heart rate. This new system uses a high resolution IR camera to track the movement of blood just beneath the surface of the skin. As part of the ‘fight or flight’ response, blood rushes towards our eyes in the instant that we tell a lie. This response is much harder for liars to learn to control than breathing or heart rate. The fact that you don’t need to be hooked up to anything means that a suspect doesn’t even have to know they are being tested. This makes for a much more accurate lie detector. Using this kind of technology, it may be possible to have a lie detector that fits on a mobile phone to test whether our friends are lying to us in everyday life. Reference
Return to top. Television shows like CSI and CSI: Miami have made forensic science a very popular area of study with many Universities around Australia now offering courses in it. But forensic S\science isn't all glamour like you see on television. There is also a side that most people never get to see and they might be pleased that they don't if they knew what it was. Smart Moves has been talking to Shari, a researcher working at the centre for Forensic Science at the University of Western Australia to find out what her average day involves. Far from solving a series of clues, each more fiendish than the last or chasing criminals across the country, Shari spends her days looking at and taking samples from dead pigs. Hardly sounds like the sort of forensic science that most people know but Shari's research can be used to help solve real murder cases. What do dead pigs have with murder cases you might ask? Well dead pigs rot in a very similar way to humans, in fact they are the best mimics of human bodies that we currently have. By looking at how long it takes a pig to break down and at the various stages it goes through we can get a good idea of how human bodies might break down. This can provide vital clues to help work out how long a person has been dead which is often a very important step in solving murder cases. Reference
Return to top. Most people are grossed out by maggots, but the little wriggly things can actually be quite helpful – especially when it comes to solving crimes. In fact, there's a field of forensics devoted entirely to bugs, maggots and creepy-crawlies – forensic entomology. When it comes to death, a close look at the insects on a corpse can help determine some important information. An approximate time of death can be calculated by comparing the size of the maggots on a body with those of known age, because the time a maggot takes to mature is largely temperature dependent. However, identification of the species of maggots can be difficult, and variations of conditions like weather and temperature can be tricky to model. Additionally, recent Aussie research has shown that the time it takes different species of insect to get to a corpse isn't always the same (it can vary year to year), which means that the end results aren't 100% accurate and should only be used as an estimate of time of death. Looking at the bugs on a corpse may also tell you if the body has been moved or disturbed after death. Different bugs are found in different surroundings (compare the bush with the beach for example), so if a body were moved after a crime, the insects on the body wouldn't match up with what you'd expect in those surroundings. Also, moving or disturbing the body after the bugs have arrived can mess up the insects' life cycles, and forensic entomologists can pick this up too. Other useful info that maggots can provide include whether or not there were any wounds on a body (something that's tricky to determine once decomposition sets in), or whether the person was under the influence of drugs before death (the maggots 'bioaccumulate' or collect the drugs from the flesh that they've eaten, so drugs can be identified even after the body has mostly decomposed). References
DNA and fingerprints are often used as main pieces of evidence in court cases. They have even been used to solve crimes that occurred many years ago. References Return to top. MycroLAB is a miniaturized laboratory capable of performing complex sample analyses previously only done in scientific laboratories. Mycrolab contains all the fittings of a traditional laboratory only smaller. The handheld device can test for diseases, contaminants or even biological weapons. Not only is it twenty times cheaper than traditional equipment, it’s fast, very fast. A typical blood test for instance would normally take several days for results to come back. MycroLAB can perform blood tests on the spot and have results back within the hour. MycroLAB inventor Micah Atkins says “it’s easy enough for anyone to use”. The sample, whether it’s blood, saliva, or water, is placed on a plate the sized credit card that slots into the side of a palm computer. Multiple tests can be performed at once. All you have to do is wait for the results to be displayed on the screen. The secret to MycroLAB is a range of microchips that are specially designed for microfluidics which is the science of building miniaturized devices with chambers and tunnels for the containment and flow of fluids. References
Return to top. DNA Profiling at the Crime Scene Being able to analyse DNA on the spot at a crime scene would allow crimes to be solved much quicker because it takes about a day to create a DNA profile in a lab. A chemist from the UK, named Tom Brown, realised this and set about trying to work out a way to analyse DNA at a crime scene. He has succeeded and managed to work out a way to create a DNA profile in one test tube and a lot faster than any of the methods that are currently being used. This is just one of the ways that forensic tools are getting smaller and forensic analysis is getting much faster. References Return to top.
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