Tuesday 29 May 2012
Definition Of Fibres
How To Become A Forensic Sciences
To become Forensic Sciences you need the following qualifications you
will need to complete a relevant undergraduate degree. Prerequisites include a
year 12 pass and one or more of the following subjects: English, maths,
chemistry, geology, biology, and psychology.
The
toughest universities to enter in forensic science in Australia are Griffith
University, Queensland University of Technology, University of Technology
Sydney, and University of Western Sydney. These all require a tertiary entrance
score of over 75. Other universities that offer bachelors in forensic science
include Canberra University, Canberra Institute of Technology, Curtin
University, Deakin University, Murdoch University, RMIT, Swinburne University
of Technology, Victoria University, Edith Cowan University, Flinders
University, Bond University, and Australian National University.
What A Forensics Science Technician Does
Forensic science technicians help investigators solve crimes by
collecting and analysing physical evidence from crime scenes. In forensic labs,
trained technicians use measuring and testing instruments, incorporating the
latest computer technology to thoroughly analyse trace evidence from crime
scenes. Forensic science technicians can:
·
Examine hair, blood and tissue samples
·
Test firearms and ballistic evidence
·
Analyse fibres, pieces of glass, wood and other
physical substances
·
Identify drugs and chemical substances
·
Recognize impressions left by fingerprints,
shoes, tires
·
Ensure proper handling and storage of evidence
What Equipment You Would Use
Analytic Equipment
Chromatographs are used to analyse different types of evidence, including
fibrous evidence. Chemicals that are unidentified are run through a
spectrograph to determine their base chemical composition.
Fingerprinring Equipment
Fingerprints are one of the
primary types of evidence used in criminal cases. The unique nature of
fingerprints makes them the next best thing to DNA samples for tying a person
to a particular location. Forensic scientists use equipment in the field such
as specialized powders, brushes, cameras and tape to capture fingerprints. They
also have computers in the lab that are used to analyse fingerprints and
compare the gathered prints to a suspect's prints or to existing databases.
Light
When a forensic scientist is
called to a crime scene, part of his job is to find evidence that is not
readily visible to the naked eye. This is done in a number of ways, including
exposing parts of the crime scene to different types of light sources. When
exposed to infrared or ultraviolet light, certain types of evidence, such as
specific types of fibres or fluids, become visible. This helps scientists find
evidence that regular investigators would not notice.
Microscopes
Real Life Case Where Fibres Were Used To Solve The Crime
Cross transfers of fiber often occur in cases in which there is person-to-person contact, and investigators hope that fiber traceable back to the offender can be found at the crime scene, as well as vice versa. Success in solving the crime often hinges on the ability to narrow the sources for the type of fiber found, as the prosecution did with their probability theory on the fibers in the Williams case.
The problem with fiber evidence is that fibers are not unique.Unlike fingerprints or DNA, they cannot pinpoint an offender in any definitive manner.There must be other factors involved, such as evidence that the fibers can corroborate or something unique to the fibers that set them apart. For example, when fibers appeared to link two Ohio murders in the 1980s, it was just the start of building a case, but without the fibers, there would have been no link in the first place.
In 1982, Kristen Lea Harrison was abducted from a ball field in Ohio and her body was found six days later some thirty miles away. She had been raped and strangled.Orange fibers in her hair looked suspiciously like those that had been found on a twelve-year-old female murder victim from eight months earlier in the same county. Since they were made of polyester and were oddly shaped (trilobal), forensic scientists surmised that it was carpet fiber.In addition, a box found near Kristin's body and plastic wrap around her feet indicated that the killer had once ordered a special kind of van seat, but then leads dried up.
Some time later, a 28 year-old woman was abducted and held prisoner in a man's home. He tortured her and appeared to be intent on killing her. When he left, she escaped and reported him. Police noticed that he had a van similar to the one into which Kristin had been forced. It proved to have orange carpeting that matched the fibers in her hair. The color was unique, which allowed scientists to trace it to a manufacturer who supplied information about its limited run. Apparently only 74 yards of it had been shipped to that area of Ohio. That helped to narrow down possibilities. Other evidence established a more solid link and Robert Anthony Buell was eventually convicted.
Fibers are gathered at a crime scene with tweezers, tape, or a vacuum.They generally come from clothing, drapery, wigs, carpeting, furniture, and blankets.For analysis, they are first determined to be natural, manufactured, or a mix of both.
Body Of Evidence (1991)
#1 New York Times bestselling author Patricia Cornwell returns to chilling world of medical examiner Kay Scarpetta in this suspense fiction classic.
Reclusive author Beryl Madison finds no safe haven from months of menacing phone calls-or tormented feeling that her every more is being watched. When the writer is found slain in her own home, Kay Scarpetta pieces together the intricate forensic evidence-while unwittingly edging closer to a killer waiting in the shadows...
A lot of the stroy was based around the orange fibre that was found at the murder scene. leding them to find who really did it. If you wish to read the book you can find it here.....
http://www.docstoc.com/docs/
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