PS- Polyethylene terephthalate, is the most commonthermoplastic polymer resin of the polyester
family and is used in fibres for clothing, containers for liquids and foods, and thermoforming for
manufacturing, and in combination with glass fibre for engineering resins.HDPE- High-Density
Polyethylene is a polyethylene thermoplastic made from petroleum. HDPE is commonly recycled and
made into composite wood or plastic lumber. is a Type 2 plastic commonly used in making containers
for milk, motor oil, shampoos and conditioners, soap bottles, detergents, and bleaches.LDPE-
Low-density polyethylene. This clear or translucent plastic exhibits flexibility, chemical resistance, and
waterproofing capabilities. It is used in the manufacture of a wide range of products, including grocery
bags, plastic wrap and film, and flexible packaging material.PC- commonly used for plastic lenses in
eyewear, medical devices, automotive components, protective gear, greenhouses, Digital Disks (CDs,
DVDs, and Blu-ray), and exterior lighting fixtures.PMMA- often used as a lighter, shatter-resistant
alternative to glass in everything from windows, aquariums and hockey rinks. Therefore, it's hard to fathom that
this easy-to-process, low-cost, versatile material is also used in dentures, bone implants etc.PETE-
polyethylene terephthalate, the chemical name for polyester. PET is a clear, strong, and lightweight plastic that
is widely used for packaging foods and beverages, especially convenience-sized soft drinks, juices and water.
*Forensicscientists can determine a number of thingsfrom analyzing hairs found at crime scenes. The clues
that hairs reveal include what part of the body the hairs came from, the race of the person they came from, if
the hairs shed naturally or were pulled from someone's head, and whether the hairs were colortreated.*
Medullary index(MI): width of medulla/whole hairwidth (if >0.5 then it is animal hair, if <0.33 then it is human
hair) Medulla: the centre-most part of the hair strandAnagen phase- period of growth in the hair cycle,avg
3-5 yearsCuticle- translucent outer layer of thehair shaft consisting of scales that cover the shaft. Cuticular
scales always point from the proximal or root end of the hair to the distal or tip end of the hair.Cortex- the
main body of the hair composed of elongated and fusiform (spindle-shaped) cells. It may contain cortical fusi,
pigment granules, and/or large oval-to-round-shaped structures called ovoid bodies.Root- the part ofthe
hair located under the skin (all previously mentioned components of the follicle are located in the shaft, which
is the part sticking out of the skin) in the tube-like structure known as the follicle. It is where the hair first
begins to grow, the underlying cells forming the protein keratin which comprises the hair.Catagen phase:
intermediate period of hair growth, 3 weeksTelogenphase: final period of hair growth resulting in hairloss,
3 months.Describe the distinguishing factors of humanhair- cuticle pattern resembles that of
unorganized, overlapping roof shingles. Only human hairs can possess fragmented or absent medulla.
Caucasian- Shaft diameter: moderate with little variation,Cross Section: oval, Pigment granules evenly
distributedAfrican-Shaft diameter: fine to moderatewith considerable variation, Cross Section: flattened,
Pigment granules: clumpedAsian- Shaft diameter:moderate with little variation, Cross Section: round,
Pigment granules: large patchy areasRidge- the line-like,raised formations that form the pattern that
forensic scientists use to analyze and identify fingerprints. By all means, they alone with the furrows they
create define the fingerprints. When they form is when a fetus gets his/her fingerprints (more notes on
fingerprint formation are listed below)bifurcation- a point on a fingerprint in which a single ridge divides into
twoisland- formation in which the ridge is shapedlike a dotenclosure- an often elliptically-shaped,
bowl-like furrow surrounded by ridgesloop- the mostcommon basic pattern of the human fingerprint,
formed by several sharply rising elongated-U-shaped ridgeswhorl- one of the basic patterns of the human
fingerprint, formed by several complete circular ridges one inside another arch - one of the basic patterns of
the human fingerprint, formed by several curved ridges one above the other3 types of fingerprints- 1.Latent, 2. visible, 3. impressionlatent- composedof
several chemicals exuded through the pores in the fingertips and are left on virtually every object touched, hard to find if possible at all, to identify a latent fingerprint,
one uses chemical testsvisible- relatively easyto find and photographimpression- still relativelyeasy to find and photographDusting- a method ofcreating a
copy of fingerprint found at a crime scene which can then be taken back to the crime lab for examination. This process centers on adhering the fingerprint oils which
left the ridge imprint to a certain substance (coming in the form of a fine powder, hence the term dusting) which can then be pulled up via specialized tape. This is
usually then attached to a note card or object of that nature so that one is left with a mirror image of the fingerprint.2 types of fingerprint powder- regular and
magnetic powderregular powder- preferable when dustingoff such surfaces as windows, televisions, kitchen counter tops, table tops, painted surfaces, cabinets
and many other surfaces found in residential and commercial settings, and it is quite effective in dustings on apprehended or stolen vehicles on painted surfaces on
the exterior of the vehicle and on glass. It also has the advantage of being available in different colors ranging from black to pink, which makes the fingerprint copy
generally more discernible against any debris that the adhesive tape may peel off the surface as well. When utilizing this type of powder, one should use a fibreglass
brush. Also, it is important to not get too much powder on it at a time, or you risk compromising the fingerprint. Lightly dapple the tip.magnetic powder- best
applied to shiny surfaces, such as plastic containers. When dusting for fingerprints with magnetic powder, crime scene investigators must use a magnetic applicator
which has a magnet. Magnetic powder is applied with a light hand with brushing strokes. Besides being available in the colors of black, white, silver/gray and
biochromatic, magnetic powder is also available in fluorescent magnetic powder colors like red and green. These can be used when dealing with problematic
background fluorescence, and they are best applied with feather duster.Chromatography- based on theprinciple where molecules in a mixture are smeared onto a
solid or surface, and a stable phase (fluid stationary phase)
separates the components of a mixture from each other
while working with the aid of a mobile phase.
Chromatography can be used as an analytical tool, feeding
its output into a detector that reads the contents of the
mixture. It can also be used as a purification tool, separating
the components of a mixture for use in other experiments or
procedures.Spectroscopy- used in physical and analytical
chemistry to detect, determine, or quantify the molecular
and/or structural composition of a sample. Each type of
molecule and atom will reflect, absorb, or emit
electromagnetic radiation in its own characteristic way.
Iodine Fuming- Self-explanatory by its
name. It was one of the earliest methods of fingerprint
development. The iodine reacts with body fats and oils in
prints.Ninhydrin- A chemical method that is usefulfor lifting
latent prints on paper. It reacts with amino acids in prints and
