trace evidence

Information about trace evidence

Published on January 29, 2008

Author: Demetrio

Source: authorstream.com

Content

The Wonderful World of Hairs and Fibers:  The Wonderful World of Hairs and Fibers Different Scopes used to analyze hair and fiber:  Different Scopes used to analyze hair and fiber Compound light Comparison Dissecting Polarized Scanning Electron Microscope (SEM) Stages of Hair “Life”:  Stages of Hair “Life” Anagen Growing stage Up to 6 years possible Root shaped like “flame” Hair grows ~1cm/month (1” every 10 weeks) Stages of Hair “Life”:  Catagen ~3 weeks long Dormant, resting stage Root gets longer and thinner Stages of Hair “Life” Stages of Hair “Life”:  Telogen ~6 months Root  Club shaped Pushes out and is shed Lose approximately 70 hairs/day Stages of Hair “Life” Human Hair Parts:  Human Hair Parts 1. Root 2. Follicle 3. Shaft 4. Tip 1 2 3 4 Human Hair Parts:  Human Hair Parts 1. Distal (tip) 2. Proximal (root end) 3. Medulla 4. Cuticle (contains scale pattern) 5. Cortex 1 2 3 4 5 Scale patterns:  Scale patterns Imbricated Mosaic Petal Pectinate Chevron Medulla Types:  Medulla Types Continuous Fragmented Intermittent/interrupted Medullary Index of Hair:  Medullary Index of Hair To find the MI Diameter of medulla/hair shaft diameter Humans = <1/3 Other animals = >1/2 Classify Medulla as: Continuous, Interrupted, Fragmented, or Absent Example Medulla Patterns that can be seen:  Example Medulla Patterns that can be seen Lattice Vacuolated Uniserial Multiserial Deer, Dog & Muskrat hair:  Deer, Dog & Muskrat hair Muskrat Deer Which is Caucasian, Negroid, Mongoloid Head Hair?:  Which is Caucasian, Negroid, Mongoloid Head Hair? Caucasian, Europeans, Mexicans, Middle Easterners: oval to round Negroid, Africans oval to flat Mongoloid, Orientals, American Indians: round Pulled Hair v. Shed Hair:  Pulled Hair v. Shed Hair Telogen stage Anagen Stage Pulled Hair Razor, Cut hair & Split hair:  Razor, Cut hair & Split hair Razor Cut Split Human eyebrow:  Human eyebrow Burned hair:  Burned hair Buckling of hair seen in pubic hair:  Buckling of hair seen in pubic hair Hair match:  Hair match This is the view that a comparison scope can give when comparing two matching hairs The small things in life:  The small things in life Eyelash mites Bedbug feeding on flesh Fibers:  Fibers Types of fibers:  Types of fibers Natural fibers Animal fibers are most common at crime scene Man-made Natural fibers:  Natural fibers Animal: Wool from sheep most common Goats, camel, alpaca, rabbit, mink, llamas, beaver Plant: Cotton most common Flax (linen), ramie, sisal, jute, hemp Excrement: Silk from silkworm (cellulose from mulberry leaves) Mineral: Asbestos Cotton fibers cross-section:  Cotton fibers cross-section Wool fibers v. Cotton fibers:  Wool fibers v. Cotton fibers Wool Cotton Flax Fibers:  Flax Fibers Hemp fibers:  Hemp fibers Silk fibers:  Silk fibers Raw thrown Wild silk Asbestos fibers:  Asbestos fibers Man-Made fibers:  Man-Made fibers Regenerated fibers Machine made from natural materials like cotton or wood 1910 rayon, then acetate, then triacetate Synthetic fibers Most fibers are made synthetically from chemicals 1939 nylon, then polyester and acrylic Shape or cross-section can determine value of the fiber; manufacturer specific Nylon fiber cross sections:  Nylon fiber cross sections Acetate Fibers:  Acetate Fibers Nylon fibers:  Nylon fibers Orlon Fibers:  Orlon Fibers Polypropylene fibers:  Polypropylene fibers

Related presentations


Other presentations created by Demetrio

21 Life Insurance
10. 01. 2008
0 views

21 Life Insurance

Common or Proper Noun
07. 02. 2008
0 views

Common or Proper Noun

AE Norman Chap1
17. 01. 2008
0 views

AE Norman Chap1

eyesafety
08. 01. 2008
0 views

eyesafety

narrative
09. 01. 2008
0 views

narrative

tup2007
10. 01. 2008
0 views

tup2007

llamas
14. 01. 2008
0 views

llamas

ISO22000
19. 01. 2008
0 views

ISO22000

WC MI growers meeting 2006
24. 01. 2008
0 views

WC MI growers meeting 2006

John Felmy
24. 01. 2008
0 views

John Felmy

Borderless 11OCT02
14. 01. 2008
0 views

Borderless 11OCT02

17971
18. 01. 2008
0 views

17971

Ethical4 Ecommerce
30. 01. 2008
0 views

Ethical4 Ecommerce

Lecture8A
06. 02. 2008
0 views

Lecture8A

mkstrgy2000
07. 02. 2008
0 views

mkstrgy2000

Incan Empire
12. 02. 2008
0 views

Incan Empire

5 coordinatesystems
13. 02. 2008
0 views

5 coordinatesystems

PILOT Slides 2006 Sec01
18. 02. 2008
0 views

PILOT Slides 2006 Sec01

Huzhou
20. 02. 2008
0 views

Huzhou

Asexual Propagation
29. 02. 2008
0 views

Asexual Propagation

agricultural revolution
03. 03. 2008
0 views

agricultural revolution

ministra geotermia final
17. 01. 2008
0 views

ministra geotermia final

carbon
20. 01. 2008
0 views

carbon

511 azhickman
14. 03. 2008
0 views

511 azhickman

Dave Harris
19. 03. 2008
0 views

Dave Harris

KELTER04
24. 03. 2008
0 views

KELTER04

CarbonMonoxide
08. 04. 2008
0 views

CarbonMonoxide

RadioAds
14. 04. 2008
0 views

RadioAds

SOUNDcd version
15. 04. 2008
0 views

SOUNDcd version

pace presentation new
17. 04. 2008
0 views

pace presentation new

Chris Harrison 1515
22. 04. 2008
0 views

Chris Harrison 1515

McMichael Amy Clinical
13. 01. 2008
0 views

McMichael Amy Clinical

roy sumit
07. 05. 2008
0 views

roy sumit

scott Mont pellier Presentation
08. 05. 2008
0 views

scott Mont pellier Presentation

francereport205
02. 05. 2008
0 views

francereport205

The PhoenixTerlinden
02. 05. 2008
0 views

The PhoenixTerlinden

TechMissionCorpsPanel
28. 02. 2008
0 views

TechMissionCorpsPanel

175734 upload 00001
07. 02. 2008
0 views

175734 upload 00001

ADJUSTED GROSS REVENUE
16. 01. 2008
0 views

ADJUSTED GROSS REVENUE

leung 2015
21. 01. 2008
0 views

leung 2015

Green Waste Recycling Cotton
28. 01. 2008
0 views

Green Waste Recycling Cotton

Tematraff 4 Mats
07. 02. 2008
0 views

Tematraff 4 Mats

pgeog251 ch17 af
20. 02. 2008
0 views

pgeog251 ch17 af

trt8ja
04. 02. 2008
0 views

trt8ja

LSRE LCM LA 1
10. 01. 2008
0 views

LSRE LCM LA 1

LaserLink May06
14. 02. 2008
0 views

LaserLink May06

Fresca
10. 04. 2008
0 views

Fresca

WWCPlenary05
06. 02. 2008
0 views

WWCPlenary05

3a asi finale ISS
09. 01. 2008
0 views

3a asi finale ISS

07GSAPropworkshop Final
22. 01. 2008
0 views

07GSAPropworkshop Final

OSCON2006 AI
10. 01. 2008
0 views

OSCON2006 AI

LDI Couch ItIsAlllHis
04. 02. 2008
0 views

LDI Couch ItIsAlllHis

Carolyns genrosity web
24. 01. 2008
0 views

Carolyns genrosity web