Forensics Lab

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Forensics Lab
Brennan Coffey
Logan Ernst
Zach Salinas
Fergus Sharp
Victim Background
Dr. Donley
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Microbiologist
Current research
concerned the Leprosy
bacteria and the Human
Immunodeficiency Virus
Recently awarded the
“Scientist of the Year”
award for her research
Throws a party to celebrate
her awards with her
colleagues at Monarch
University on March 11,
2011 at 7 p.m.
Dr. Donley
Incident Overview
Dr. Donley found injured
in her lab at 2:00 a.m.
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Victim of attacks
Suffered minor injuries,
including a concussion and
lacerations to the hand and
back of the head
Two vials containing
pathogens from Dr.
Donley’s research were
missing from the level IV
containment room
Incident Overview – Part II
Further examination of the
victim revealed she had been
bludgeoned to the back of the
head
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Dr. Donley unable to remember
her attacker
Her glass also had traces of
cyanide on it, indicating that
someone had attempted to
poison her
After collecting more
information, it was determined
that Dr. Donley had ended the
party at 12:00 a.m. after
discovering the cyanide on her
glass
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Scent of almonds indicative of
cyanide
Crime Scene Analysis
19 suspects
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All attended party
3 of interest were interviewed
Dr. Sloopy Stretch
Danica Market
Dr. Kelvin High
Blood under Dr. Donley’s
fingernails and on her hand
Lip prints on two glasses
matching Dr. Donley and
another unknown individual
Fingerprints of Dr. Donley and
another unknown individual on
a glass
Pet hair found on Dr. Donley’s
Lab coat sleeve
Hair Analysis - Method
Structure Analysis
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Length and shape help
determine the area of the
body the hair came from
Root – stage of growth of
the hair, and indicates
whether hair fell or was
pulled out
Shaft – contains unique
characteristics to
individuals and
populations, and indicates
age and condition of hair
Tip – indicates any recent
exposure (haircuts,
chemicals, burning)
DNA Analysis
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Run hair follicle through
enzyme cocktails to
remove cellular coatings
and organelles
Centrifuge the sample to
separate out DNA
Use PCR method to create
copies of the segment of
interest in the DNA
Target marker sites to
separate out and create
copies of specific sections
of the DNA sequence
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Compare the DNA sample
to suspect database
Hair Analysis - Results
Two samples found at the
scene
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One determined to be
animal hair, based on
structure analysis
The other determined to be
hair from a human male
DNA analysis revealed the
human male hair belonged
to Dr. Kelvin High
The animal hair most likely
belonged to a dog. Dr.
Kelvin High has a Beagle
Lip Print Analysis
Lip print analysis at this scene
is done primarily by visual
comparison
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Lip print samples were
provided
It was determined that sample
A appeared on the napkin at
the scene
Sample C appeared on the
standing glass
Sample D appeared on both
the standing and the knocked
over glass
Lip print comparison can be
used like fingerprint analysis,
but it is rarely used in forensic
science – infrequent samples
Blood Analysis - Method
Confirmation
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Potential crime scene
blood is sprayed with
luminal spray
If the sample glows under a
blacklight, it is a blood
sample
Human Confirmation
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Sample is placed on a gelcoated test plate
Testing solution and blood
sample will defuse towards
each other
Noticeable band will form in
the middle and will contain
human antigens if positive
Blood Type Analysis
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Human blood analyzed
according to the ABO
system of antigens
A, B, and O are antibodies
attached to the surfaces of
red blood cells
Blood samples are mixed
with known samples of A
and B
If the sample clumps with A
blood, it is also A-type. The
same is true with B to B
Blood Analysis – Method Cont.
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If clumping to both occurs,
the sample is AB
If no clumping occurs, the
sample is type O – no
antibodies
RH Factor Analysis
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RH factor is a protein
Indicated in blood types by
+ or –
The same clumping
matching tests are used for
this protein
If clumping occurs, the
blood sample is + for the
RH factor. If not, the
sample is –
Therefore, each blood type
has a + and – version
Blood Analysis - Results
Blood found under Dr.
Donley’s fingernails
and on the knife were
both of the B- type
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This matches Dr.
Kelvin High
Fingerprint Analysis – Method
Dactylography
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Used to determine the
percent similarity of a crime
scene fingerprint to a
known fingerprint in a
database
The comparison uses
analysis of features:
whorls, arches, and loops
Fingerprints are all
individual, no two are alike
Fingerprints
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These are residue marks
from human skin oils left in
the imprint of the
individual’s finger
They are picked up with
various compounds that
are powdered and/or
magnetized
The type of compound
depends on the surface of
which the print will be lifted
from
Fingerprint Analysis - Method
Database Analysis
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Divided between value
and no-value patterns
Value patterns are the
various whorls
No-value patterns
include the loop and
arch based patterns
Prints given numbers
based on finger they
come from and pattern
types
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Each fingerprint has a
code associated with it
Allows for database to
sort to find similar prints
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Computer system
analyzes the distances
between ridges, their
starting positions, and
their patterns
Other features, such
as dots and enclosed
areas, are also used in
comparisons
Fingerprint Analysis - Results
After visually
comparing patterns of
various crime scene
prints, it was
determined that Dr.
Kelvin High was
present and had
played a role
Fingerprints of Dr.
Sloopy Stretch also
found
Stolen Pathogens - Leprosy
Mycobacterium Laprae - Hansen’s Coccus Spirilly
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Bacteria often found in warm, tropical countries
Aerobic, rod-shaped bacterium with a waxy coating
characteristic of mycobacterium
The first bacterium found to cause disease in humans
has a complex and unique cell wall that makes it difficult to kill
This also makes it replicate slowly – slowest of all known bacteria
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The bacterium has never been successfully grown in artificial
culture plates
Due to the fact that it lacks many necessary genes for independent
survival
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Has, however, been grown on mouse foot pads in laboratories
Stolen Pathogens – Leprosy
Symptoms
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Main symptom or sign of
leprosy is skin lesions
Causes numbness of the
limbs, dry scalp, vision
problems and muscle
weakness
Left untreated, leprosy can
cause permanent damage
to the skin, nerves, and
eyes
Treatment
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A cocktail of multiple drugs
often including rifampicin,
clofazimine, and dapsone
is used
Drugs quickly kill the
disease causing bacterium,
but do not immediately stop
the symptoms
This indicates that many
symptoms of leprosy are
caused by damage to cells,
and not simply the
presence of bacteria
Stolen Pathogens - HIV
Human Immunodeficiency Virus - Background
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A human condition that can eventually lead to
acquired immunodeficiency syndrome (AIDS)
It allows for life threatening infections to occur due to
a deficient immune system
HIV infection occurs with the transfer of semen,
vaginal fluid, breast milk, and or blood
AIDS has killed more than 25 million people since its
discovery and is considered to be a pandemic by
WHO
Primarily infects vital cells in the immune system such
as helper T cells, macrophages, and dendritic cells
Stolen Pathogens – HIV Cont.
Virus Specifics
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HIV belongs to the genus Lentrivirus
Lentriviruses are often responsible for long-duration illnesses
with long incubation periods
Transmitted as single stranded, enveloped RNA viruses
Upon entry to a target cell, the virus’ genomic RNA is transcribed
as double stranded DNA
Viral DNA is then introduced to the cell nucleus, and integrated
into the cellular DNA
The virus becomes latent once integrated to the cellular DNA,
allowing it to remain undetected by the immune system
Once the viral DNA is part of the cellular DNA, the cell will
produce viral proteins
Stolen Pathogens – HIV Cont.
Virus Specifics Cont.
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HIV has three stages: acute infection, latency, and
AIDS
The acute phase lasts 2-4 weeks
Victims will suffer symptoms similar to those of influenza or
mononucleosis
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Latency can last 2 weeks to 20 years
This stage is primarily in the lymph nodes, which can become
chronically swollen
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Once AIDS is reached, many opportunistic infectious
diseases can attack
AIDS is characterized as a T cell count lower than
200 cells per microliter
No resistance to infections once AIDS is reached
Suspect Interviews
Danica Market
Information obtained from
interview:
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Was there for the entire
party
Shoe size 7
Pet Ferret
Admires Dr. Donley and
her award
Was wearing pink lipstick,
along with many other
patrons
No to limited knowledge of
pathogens
Dr. Sloopy Stretch
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Shoe size 11 (matches
print at scene)
Admits to being at the party
and scene the entire time,
but appears to have limited
involvement in the party
itself
Suspected by other
suspects, including Dr.
Kelvin High
Suspect Interviews – Cont.
Dr. Kelvin High
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Limited knowledge of
pathogens
Specializes in Physics
Has a pet dog - beagle
Shoe size 7.5
Claims he wasn’t invited to
the party (motive?)
Does not read newspapers
– therefore did not rip the
newspaper found at scene
Signed the Insurance
Policy on behalf of Dr.
Donley for own benefit
Dr. Donley has insulted his
alternative to string theory
Wants to prove Donley
wrong about his theory at
any cost
Case Conclusion
After reviewing all case
information, the following
has been concluded:
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Dr. Sloopy Stretch was
present on scene and stole
the pathogens
Has previous history of
breaking into Dr. Donley’s
Lab – jealous of lab
technology
Shoeprint, size matching,
found next to Dr. Donley’s
body
Act of sabotage after
Donley had been attacked
Case Conclusion – Cont.
Dr. Kelvin High is the
attacker
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Hair matched to the scene
Dog hair found on the
scene – has a beagle
Matching blood type found
under Donley’s nails and
on other objects in the lab
Fingerprints found in lab
Motives:
Receive benefits of the
insurance policy he forged
Anger towards Dr. Donley
for not recognizing his
theory and for not inviting
him to the party
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Resorted to physical attack
after cyanide efforts failed
Tried to blame Dr. Stretch
after seeing him on scene
The Verdicts
Fortunately, the man of
the millennium did not
visit Dr. Donley on the
night of the party
Drs. Stretch and High
were apprehended
Dr. Stretch’s trial dragged
out, but was eventually
ended with sentences for
theft and non-compliance
Dr. High’s trial was a
short one, with the Dr.
being sentenced for
assault and battery
Works Cited
"Computer Forensics | Forensic
Science | Mysteries | Lesson Plan
at Exploreforensics.com."Lesson
Plan | Forensic Science | Crime
Scene | Unsolved Mysteries at
Exploreforensics.com. Web. 26
Apr. 2011.
<http://www.exploreforensics.com/
>.
"Forensic Science." Shambles in
S.E.Asia (The Education Project
Asia) at Www.shambles.net. Web.
26 Apr. 2011.
<http://www.shambles.net/pages/l
earning/sciencep/forensic/>.
"Forensic Science." The Science
Spot. Web. 26 Apr. 2011.
<http://sciencespot.net/Pages/clas
sforsci.html>.
Ms. Donley’s Lectures
Officer Christy’s Forensics
presentation
Wikipedia – Various pages
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