Question 5b-Considering the evidences available up to this point in time, describe in detail how you would go about investigating further, assuming you are Dr. Rudi or Dr. Suria, explaining what you anticipate at each step

As a mere dental investigator, it would be challenging to resume the role of Dr Rudi or Dr Suria, neverthless I'll try my best !☻

(In Dr Rudi's shoes,acting cool and composed) {momentary bliss} 

So now,what do we have here? A well preserved facial skull, a large missing piece of cranial skull, a maxilla with absolutely no maxillary dentition, and a mandible with only molars and a lot of missing teeth. And not to mention, a child's mandible with only a visible canine. Hmmm...let's put our brains to work now.

From all the evidences displayed before us, I suggest we should start our investigation from the teeth! What are your opinions people? No objections? Ok then let me express my view on this!✌

Teeth are the most durable part of the human body. The enamel is 98 percent inorganic and less susceptible to decay than soft tissue or even bone. And like a fingerprint, no two sets of teeth are identical so dentitions are undeniably helpful in identification,agreed? 
Also, tooth eruption can prove particularly beneficial in determining age, especially in the forensic aspect, it definitely narrows the scope. The presence of wisdom teeth also indicates the victim is above the age of 18, as shown in this case. In younger individuals,such as the case of the child mandible, the presence of deciduous teeth, also known as milk teeth, suggests the victim is an infant or child, as these teeth tend to be lost by around age 12. Such as in the child mandible case, the presence of the canine indicates that the child is most probably 22 months or older as the eruption date of canines is 16-22 months. Unfortunately,the rest of the teeth are missing so no further conclusions can be drawn. (The list detailing the age of eruption of each tooth has been provided in part I.)

Tooth compare (left belong to a child, right belong to an adult )

(Twirling pen around fingers subconsciously) {totally immersed in the role}

(Adjusting lab coat and clearing throat loudly before speaking again) {startling people around}

Guys,may I? {people around nod unanimously} (as if they can ever say no *joking joking*) 

There is actually very reliable method in assisting our investigation tremendously,that is
FORENSIC FACIAL RECONSTRUCTION


It is a process of recreating the face of an individual whose identity is often not known from their skeletal remains 
There's some example about forensic facial reconstruction

Cold-case murders of 4 females brought back to life by forensic facial reconstruction

The remains of a woman between 23 and 33 (far right) were found in Allenstown, New Hampshire, in 1985. Remains of the girl second from left were found in the same barrel. The other two bodies were discovered in 2000.

PROCEDURE

This video shows how amazing forensic facial reconstruction has contributed in forming back a skull.

A clay model is formed!! ♥

This method doesn't sound too bad eh? Athough this may not be used as a sole identifier, the image may be distributed amongst the public, hopefully prompting people to come forward and make a positive identification. Helpful much? (not bad! not bad at all!)

But of course! In this highly developed and advanced 24th century with lots and lots of electronic devices (iPad,iPhone-thank you Steve Jobs!,not exactly for me though,Samsung is more for me haha,ok back to track!) and also lots of media,facilitating our means of communication (Facebook,Instagram,Twitter,Whatsapp hahaha! not to mention...) okok!! Anyways, now there is 
3D FACIAL RECONSTRUCTION


This can allow for the better manipulation of the image and easy transfer between computers.

For Instances,

This is the face of King Richard III, reconstructed from 3D scans of his skull after the positive identification of his skeleton found beneath a social services car part in Leicester last year

The skull is rotated whilst a laser scanner is used to produce a 3D image of the skull. Previously-obtained computed tomography scans of actual living people are used to determine the muscle, fat and skin to be placed over the skull, the profiles used selected based on their similarity to the victim. 

[PS.These methods are often preferred as they are non-destructive to the skull, so if errors are made, the process can be repeated without altering the evidence.]

Well well, almost everyone who has visited a dentist has a record of their teeth or X-rays,which are very useful in the identification of a victim.

Dental mapping techniques by comparing the skull or teeth of victim with prior dental records

PORTABLE X-RAY EQUIPMENT & DENTAL MAPPING TECHNIQUE can be used to develop profiles of the victims. In some cases, those profiles can be compared to prior dental records that have been scanned into a computer, allowing experts to make matches or at least narrow the possibilities.

After the reconstruction of the skull, we are able to identify the victim. However, we need to enhance our evidence by compare the DNA of victim to his/her famiy member, to ensure that its the correct person.

SO, HOW TO COMPARE THE DNA OF VICTIM WITH THE FAMILY MEMBERS?

Well, things like hair , saliva , blood . All these can be collected and perform DNA TESTS

For instances,  Polymerase Chain Reaction (PCR )
WHY use PCR ?
It is because, PCR can amplify and quantify the DNA, which play vital role in forensic analysis as it works even when there is only trace amount of DNA as evidences.
 PCR help in selective DNA isolation. PCR fingerprinting methods help to identify genetic relationships between individuals, such as the victim with his/her parents, and with the siblings.

Firstly, place the samples of reaction mixture in PCR tubes

Undergo electrophoresis of PCR-amplified DNA fragments 



Compare the DNA bands of the victim with the parents and siblings
This DNA fingerprinting shows how similar the DNA of victim to the family members.

Afterall, hope that with these procedures, we.re one step closer to the truth and the identity of the victim is able to be identified.

(self satisfaction)

*applause applause* (doing the hand wave) 

Now that all of you understand the methods of investigation, maybe anyone of you can be Dr Rudi! haha. It's actually quite amazing to witness the tremendous development in the realm of forensics and the inventions men have created for the contribution to this field. Now we know that forensics is actually a tough job eh? But I also personally think it's very rewarding and that the forensic pathologists have indeed done their parts in delivering justice to victims. 

WE NOW SEE THE LIGHT!!

Bye! And enjoy your weekend peeps!

Reference List

http://forensicsciencecentral.co.uk/anthropology.shtml

http://www.skeptictank.org/gen1/gen00504.htm
http://www.dailymail.co.uk/sciencetech/article-2273703/Richard-III-facial-reconstruction-reveals-slain-king-500-years-death.html
http://edition.cnn.com/2013/06/14/us/new-hampshire-bodies-mystery/index.html

Questions 5
List the evidences that have been presented to both the doctors.

The Mills Of God Grinds but eventually 

Well, what made me said that?

Its because Dr Rudi and Dr Suria have found some evidences related to the murder case, which means they getting closer to the TRUTH

Firstly, both the doctors have found a adult's skull which has a well preserved facial skull ,a maxilla withh no maxillary dentition, and a large mandibular jaw bearing with

teeth

Moreover, a mandibular jaw which broken into pieces.  Its composed of 3 posterior teeth- first molar, second molar and third molar.





Besides, the doctors have also found a child jaw, which teeth are broken, only left an obvious canine and some other teeth which still undergo eruption.
However, the child mandibular jaw does not broke into pieces.

4.3 Wherever You Go, You'll Leave A Mark

Hey guys ^.^

This is an extra information that I added. (:

When victims are found fresh, we can use another method call.....

Fingerprint Analysis

Fingerprinting analysis has been used for more than a century, yet it is still widely used in law enforcement agencies.  Because of its unique characteristic, it is conclusive evidence and a valuable tool among advanced technology even today. 

However, there is a chance it might lose its ground by DNA fingerprint, which is more sophisticated and accurate than traditional fingerprint.

There are 3 types of fingerprints that exist at crime scenes:

  1)   Visible prints are made from finger stained with colored materials such as ink, blood, and grease. 

  2)    Plastic prints are formed by pressing onto a soft surface such as clay, soap, and wax. 

3)    Latent print is an invisible print left on an object by the body’s natural greases and oils.  Because it cannot be seen by naked eyes, fingerprint powders, chemicals, and even lasers are used to make it visible on the crime scene evidence.

Loops (65%)	Archers (30%)	Whorl (5%)
Lines that enter and exit on the same side of the print	Lines that start on one side of the print, rise into hills and then exit on the other side of the print	Circles that do not exit on either side of the print
Subdivided into: Radial loop Ulnar loop	Subdivided into: Plain arch Tented arch	Subdivided into: Plain whorl Central pocket whorl Double loop Accidental whorl

SIMPLIFIED FINGERPRINT ANALYSIS

WHY USE FINGERPRINTS IN A IDENTIFYING MURDER VICTIMS

According to most professional criminal investigators, fingerprints obey three fundamental principles. These principles are:

1. A fingerprint is an individual characteristic. It is yet to be found that prints taken from different individuals possess identical ridge characteristics (even in twins).

2. A fingerprint will remain unchanged during an individual’s lifetime. (The friction ridges which create fingerprints are formed while inside the womb and grow proportionally as the baby grows)

3. Fingerprints have general characteristic ridge patterns that permit them to be systematically classified.

The individuality of any fingerprint is based not upon the general shape or pattern that it forms, but instead upon its ridge structure and specific characteristics (also known as minutiae).

The recognition of these ridges, their relative number, and the approximate location of them, on the observed print, are the special characteristics that make the fingerprint a specific identifying characteristic of each individual.

There are at least 150 individual ridge characteristics on the average fingerprint. If between 10 and 16 specific points of reference for any two corresponding fingerprints identically compare, a match is assumed.

 

Surfaces Characteristics & Collection Methods

Characteristics of the surface in which the print is found are important in deciding which collection methods should be employed on scene.

The general characteristics of the surface are: porous, non-porous smooth and non-porous rough.

Porous	Non-porous
	smooth	rough
Able to absorb liquid	Not able to absorb liquid
Scientist sprinkle chemical like nynhydrin over the prints and then take photographs of the developing fingerprints	Experts use powder-and-brush techniques, followed by lifting tape	Same powdering process should be used, but gel-lifter or Mikrosil is used to effectively left a print
Paper, cardboard, untreated wood	Varnished, painted surfaces, plastics and glass	Vinyl, leather, other textured surfaces

Analysis of Collected Prints

During analysis, examiners determine whether there is enough information present in the print to be used for identification.

This includes determining class and individual characteristics for the unknown print.

The three fingerprint class types are arches, loops, and whorls. They are tiny irregularities that appear within the friction ridges and are referred to as Galton's details. The most common types of Galton's details are bifurcation, ridge endings, and dots or islands.

Classical method for developing latent prints on paper or other porous object by using nynhydrin

Check out this video to learn the technique of Using Mikrosil to Lift Fingerprints from Irregular Surfaces. (:

Comparison of Prints 


After an examiner completes the analysis, they compare the unknown print side by side with a known print. The unknown print is the print found at the crime scene, and the known print is the print of a possible suspect.

First, the class characteristics are compared. If the class characteristics of the two prints are not in agreement, then the first print is automatically eliminated. If this is the case, another known print may be compared to the unknown print. If the class characteristics appear to match, the examiner then focuses on the individual characteristics. They look at each individual characteristic point by point until they have found a possible match.

Evaluation of Comparison


After the examiner completes the comparison, they can make a proper evaluation.

Scenario 1 -Exclusion

If there are any unexplainable differences between the unknown and known fingerprints, then they can exclude the known fingerprint as the source. This means that if the class characteristics are in disagreement, then the conclusion would be exclusion.

Scenario 2 - Identification

However, if the class characteristics as well as the individual characteristics are in agreement and if there are no unexplainable differences between the prints, the conclusion would be identification.

Scenario 3 - Inconclusive

In some cases, neither of these conclusions is possible. There may not be a sufficient quality or quantity of ridge detail to effectively make a comparison, making it impossible to determine whether or not the two prints came from the same source. In these instances, no conclusion can be made and the report will read "inconclusive."

Verification of the Evaluation 


After the first examiner reaches one of the three conclusions, another examiner must verify the results. During this verification process, the entire exam is repeated. The second examiner does the repeated exam independently from the first exam, and for an identification conclusion, both examiners must agree. If they agree, the fingerprint evidence becomes a much stronger piece of evidence if and when it goes to court.

Databases such as AFIS (Automated Fingerprint Identification System) have been created as ways of assisting the fingerprint examiners during these examinations. These databases help provide a quicker way to sort through unlikely matches. This leads to quicker identification of unknown prints and allows fingerprints to be as widely used as they are in criminal investigations.

Picture from: http://forensics4fiction.files.wordpress.com/2011/08/dsc_0100.jpg

After reading this post, i'm sure that we will understand more and know how things in the  TV series CSI works. 

Have fun reading. (:

DI.

References:

http://sites.bergen.org/forensic/fingerprint.htm (lat visited 11 Oct 2013)

http://www.handanalysis.net/beginners/fingerprint_types.htm

http://www.crimemuseum.org/library/forensics/fingerprints.html (last visited 11 Oct 2013)

4.2 Helical Structures that Tell Us Everything

Welcome to part 2 of question 5. (:

Besides forensic anthropology, we can also identify victims with DNA Profiling.

The term DNA profiling - or genetic fingerprinting - is applied to the scientific process whereby samples of DNA are collected, collated and used to match other samples of DNA, which may have been found at the crime scene.

 James Watson & Francis Crick

Founder of DNA ,1962

James Watson in 2003

Examining sequencing gel as a part of DNA profiling.

http://science.howstuffworks.com/dna-profiling.htm

Why use DNA Profiling?

This process is used as one means of identification when an attacker or assailant has left some kind of bodily fluid or blood at the scene of a crime and when no visual identification is possible.

DNA profiling relies heavily on the principle that no two individuals share the same genetic code - except for identical twins and statistically those elements of DNA that are examined and used to obtain a match will be unique.

The process of DNA fingerprinting was first used during the 1980's and its application was quickly to become that of identification of suspects involved in serious crimes including murder. The premise that most attackers or killers will leave some measure of bodily fluid at a crime scene - be it saliva, blood, semen or other such fluid - was quickly accepted as common place and it became a staple of many criminal investigations.

Blood stain at crime scene

Collecting Evidence

Just like normal fingerprints taken from a suspect they are so unique that only in the case of identical twins - as we have already mentioned - could they be the same.

http://www.cartoonstock.com/lowres

Statistically there is a one in sixty-four billion chance that any two unrelated individuals would have comparable DNA: comparable DNA is DNA that has certain attributes similar to that of another person but is not identical. This can be used as evidence in a court of law however most defence or prosecution counsels would tend not to rely heavily on it if there are only certain similarities.

Procedures used in DNA Profiling

Restriction Fragment Length Polymorphism Restriction enzymes are used to cut segments of a sample from which DNA is extracted. The procedure of RFLP focuses on repetitious sequences of DNA 'bases' which vary greatly from individual to individual.

These segments are then separated using a technique called Electrophoresis, which measures each of them by length. Once they have been sorted in this way a visual representation of the results is created using a procedure known as Autoradiography: basically producing an x-ray of the results that can be compared by overlapping the x-rays.

http://science.howstuffworks.com/dna-profiling1.htm

Steps for RFLP:

1.                 Separate white and red blood cells with a centrifuge.

2.                 Extract DNA nuclei from the white blood cells. This is done by bathing the cells in hot water, then adding salt, and putting the mixture back into the centrifuge [source: University of Arizona].

3.                 Cut DNA strand into fragments using a restriction enzyme.

4.                 Place fragments into one end of a bed of agarose gel with electrodes in it. Agarose gel is made from agar-agar, a type of seaweed that turns into gelatin when dissolved in boiling water.

5.                 Use an electric current to sort the DNA segments by length. This process is called agarose gel electrophoresis. Electrophoresis refers to the process of moving the negatively-charged molecules through the gel with electricity. Shorter segments move farther away from their original location, while longer ones stay closer. The segments align in parallel rows.

6.                 Use a sheet of nitrocellulose or nylon to blot the DNA. The sheet is stained so the different lengths of DNA bands are visible to the naked eye. By treating the sheet with radiation, an autoradiograph is created. This is an image on x-ray film left by the decay pattern of the radiation. The autoradiograph, with its distinctive dark-colored parallel bands, is the DNA profile.

Short Tandem Repeat Test

A more recent form of test is the STR Test (Short Tandem Repeat Test), which looks at DNA segments and counts the number of repeats at a number of different DNA sites - normally around thirteen.

http://www.hawgoodfamily.co.uk/wpimages/wpa5479d92.jpg

Polymerase Chain Reaction

Another more recent test - can create multiple copies of the DNA sequence using as little as fifty molecules; this procedure can help to produce a usable DNA sample from a single human hair.

It is worth noting that all of these tests have proven very reliable over the years and continual advances in forensic science - and genetic fingerprinting as a whole - have made these tests almost foolproof!!!!

The chances of any of these results leading to the misidentification of a suspect is one in several billion and over the years since their inception these tests have also not only proved the guilt of many suspects but have also proven the innocence of many people wrongly convicted of a crime at a time when DNA fingerprinting was not available.

http://users.ugent.be/~avierstr/principles/pcrsteps.gif

Ok guys, let's end this topic with a video. (:

That's it. Happy Learning. 

DI

References:

http://www.exploreforensics.co.uk/dna-fingerprinting.html (last visited 13 Oct 2013)

http://science.howstuffworks.com/dna-profiling1.htm