Hair Analysis What is Hair Hair Appendage of
- Slides: 25
Hair Analysis
What is Hair?
Hair= • Appendage of skin • Grows out of a hair follicle • Root, Shaft and Tip
Layers of Shaft Medulla Cortex Cuticle
Cuticle Layer • Tough and Resistant Outer Layer • Overlapping scales made of keratin • Used for species identification
Casting to see scale pattern
Cortex Region • Beneath Cuticle • Contains pigment granules that give color to hair • Look at color, shape and distribution of granules
Medulla Region • Center Region of Hair • Presence and pattern varies from person to person and from hair to hair on an individual Uniserial Multiserial Vacuolated Lattice Fragmented Intermittent Continuous Amorphous
Medulla • Human hairs generally have Fragmented or Absent medulla • Exception: Mongoloid/Asian - usually have continuous medulla
Roots • Necessary for growth of hair • Can tell the growth stage of hair: – Anagen= Actively growing, root is flame shaped – Catagen= Slowed growth, root elongated and shrunken – Telogen= Hair growth ends, root club-shaped, hair falls out of follicle
Roots Follicular Tissue Catagen Anagen Telogen
Hair: Comparative Studies • • • Need comparative microscope Need multiple hairs for comparison Look at overall color, length and diameter Medulla absent or present? Distribution, shape, color intensity of pigment granules in cortex
Hair: Comparative Studies • • Dyed Hair (Paint Roller)vs Natural? Bleached Hair (Yellowish tint) Time of Dyeing? (Hair grows 1 cm/month) Nits or fungal infections?
Hair: Comparative Studies • Types: – Scalp= uniform diameter and pigment distribution – Pubic= short, curly and diameter variations – Facial=Coarse, triangular, blunt tips
Hair: Comparative Studies • Race: – Black= Tight curls, dense uneven pigment distribution, flat to oval hair in cross section – Caucasian= Straight or wavy, fine to coarse pigments that are evenly distributed, oval to round hair in cross section
Hair: Comparative Studies • Age and Sex: – Age and Sex Determination= Most No, – Baby Hair short, thin and fine pigment
Hair: Comparative Studies • Forcibly Pulled Hair – See follicular tissue at root • Isolate Nuclear DNA • Telogen hairs not a good source for DNA • Mitochondrial DNA
Hair: Comparative Studies • Drug use/ Poisoning
Hair Collection • Need control samples • Need at least 50 scalp hairs from an individual • Need at least 20 pubic hairs from an individual • Need full length hair
Cut close to scalp, need minimal amount of head and body hair
• http: //www. youtube. com/watch? v=Z 9 L com/watch? v=Bd 170 NWE i 3 MC 4 d-Hm. Y • http: //www. youbea uty. com/hair/videothe-science-of-hair
- Epidiymit
- Jointed appendages meaning
- Right atrial appendage
- Cpt code for left atrial appendage ligation with atriclip
- Dark hair and blonde hair parents
- Uses of tacheometric surveying
- When everybody wears a uniform the rebel dresses in
- Hair grows in diagonal tubes called hair
- Difference between animal and human hair
- Heterozygous tabby x stripeless
- Root sheath
- Canities
- History of hair analysis
- Heidi with the blue hair
- Hair type
- Horizontal lines in hair
- Keratin definition forensics
- The cutting of my long hair analysis
- For heidi with blue hair
- The most common type of plant fiber is
- My parents poem
- Bernice bobs her hair analysis
- Is hair class or individual evidence
- Disadvantages of structured analysis
- Autohotkey obfuscator
- Discourse analysis vs content analysis