Forensic science engages students in the application of scientific principles and methods for the evaluation of evidence. The field of forensic science has received extensive exposure in recent years and is now regarded as a highly respected discipline among scientists and criminalists. Forensic science encompasses a wide array of disciplines including criminology, pathology, toxicology, etc. The educational background of professionals in this field is embedded heavily in the natural and behavioral sciences such chemistry, biology, physics, sociology and criminal justice. The mission of the Bachelor of Science Degree Program in Forensic Science is to produce technically skilled graduates equipped with the basic foundational science and laboratory problem solving skills necessary for success in the modern crime laboratory, and who will contribute to the advancement of the forensic science community. Students will receive preparation in areas such DNA analysis, forensic chemistry and trace evidence. The program will also provide students with the knowledge and skills needed to prepare reports documenting their findings and laboratory techniques used, and to provide expert witness testimony based on these findings. Upon completion of the Forensic Science program graduates will be prepared to function as forensic scientists and specialists, or for advanced study in areas such as forensic science, biomedical research, medicine and law.
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In 1877 at Hooghly (near Kolkata), Herschel instituted the use of fingerprints on contracts and deeds, and he registered government pensioners' fingerprints to prevent the collection of money by relatives after a pensioner's death. 
The principle behind the test is that Phadebas®, consisting of starch microspheres with a blue dye cross-linked to the starch, are immobilised on filter paper sheets. In the presence of amylase the starch is digested, releasing the water soluble dye, which diffuses through the pores of the filter paper. The resulting blue colour is visually observed on the non-reagent side of the Phadebas® paper. The Press test is performed when it is necessary to localise an amylase positive area on an item. If a very strong reaction is obtained with the Press test and there is no other obvious contaminating material, this is interpreted as an indication of saliva. The following link illustrates the methodology and simplicity with an Overview of Phadebas Forensic Press Test . For detailed instructions; please follow Phadebas Forensic Press Test Instructions .
In-house testing at several independent forensic laboratories has determined that no other forensically relevant body fluid (sweat, semen and vaginal secretion) will react within 10 minutes using the current protocol, even after repeated deposition. The exception is faecal stains that may contain levels of amylase as high as those found in saliva. For this reason positive observations within areas obviously contaminated with faeces should not be interpreted for the presence of saliva. The presence of potential faecal material on an item should be recorded in the examination notes. In an independent trial performed in UK it was demonstrated that saliva from the most common pets did not give rise to any false positives.
To assure selectivity for saliva, the papers must not detect stains with an amylase activity below 2000 units/L within 40 minutes testing time. It has been demonstrated in several scientific articles that saliva dilute 1:100 can be easily be detected. For further info, please visit the Phadebas Archive .
The Phadebas Forensic Tube Test is more sensitive than the press test and used semi-quantitatively for the presumptive testing of saliva deposits. If it is suspected that the stain to be tested is a weak saliva stain, or if testing the supernatant from an extracted stain or swab, Phadebas tube test offers a better method than using Phadebas paper. A tube test may also be carried out if amylase is detected (using the Phadebas® Forensic Press test) in an area that exhibits other staining such as semen, blood or heavy vaginal deposits. The Tube test is used in two ways; qualitative and quantitative. The qualitative test relies in the observable colour difference between the positive test and a blank whereas the quantitative test makes use of absorbance spectrophotometry to exactly measure the α-amylase activity.
* An Improved Test for the Detection of Salivary Amylase in Stains, Willott, G. M., Journal of the Forensic Science Society; 1974; 14: 341-344
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