ABC test
Alphonse Bertillon
Anthropometry (replaced by fingerprints)
Base (Bronsted-Lowry)
- a substance that accepts a proton (H+) - tends to add OH- ions to H2O - increases pH
Acid (Bronsted-Lowry)
- a substance that donates a proton (H+) - increases [H+] when dissolved in H2O which lowers pH
DNA synthesis
Always proceeds in a 5' to 3' direction
catagen phase
- The brief transition period between the growth and resting phases of a hair follicle. It signals the end of the growth phase. - 2 to 3 weeks
agarose gel
- a jelly-like slab used to separate molecules on the basis of molecular weight - large pore - 2000 angstrom
ASCLD (American Society of Crime Laboratory Directors)
"To promote the effectiveness of crime laboratory leaders throughout the world by facilitating communication among members, sharing critical information, providing relevant training, promoting crime laboratory accreditation / certification, and encouraging scientific and managerial excellence in the global forensic community."
circumstantial evidence
(indirect evidence) evidence used to imply a fact but not prove it directly
ABO blood groups
- 4 phenotypes: A (AO, AA) B (BO, BB) O (OO) (40% of population) AB (AB)
covalent bond
- A chemical bond that involves sharing a pair of electrons between atoms in a molecule - between nonmetals
Proton
- A subatomic particle that has a positive charge and that is found in the nucleus of an atom - 1 proton = 1.0073 amu
acid phosphatase
- An enzyme found in high concentration in semen - prostate
Amylase
- Enzyme in saliva that breaks the chemical bonds in starches - alpha in animals - beta in plants - amy1 in saliva, breast milk, and perspiration - amy2 in pancreas, semen, and vaginal secretions
1st Amendment
- Establishment clause - Free exercise clause - Freedom of speech, press, and assembly
August Vollmer
- Father of American police professionalism - 1st crime lab (LAPD) - police chief from Berkley
atomic mass
- The average mass of all the isotopes of an element - number of protons and neutrons
Presumptive Blood Tests
- alder: benzidine (enzymatic) blue in acid - KM: hemoglobin catalyzed clear to pink - o-tolidine= enzymatic - LMG: oxidation, colorless to green - TMB = enzymatic, green/blue in acid
Amu
- atomic mass unit - 1 amu = 1.66E-24
Controlled Substances Act of 1970
- classifies controlled substances according to their abuse potentials - 5 schedules
aperture
- depth of field - adjustment of lens opening (f number) - decrease opening = decreased light - increases depth of field and diffraction blur
DTT
- dithiothreitol - lyse sperm cells - strong disulfide reducing agent - disrupts sulfur bonds releasing DNA into solution
ABC Code of Ethics
- follow ABC rules -confidential -ensure evidence integrity -analyze all probative evidence -standards and controls -don't use inaccurate or unreliable techniques -full disclosure -contemporaneous notes -opinions based on evidence -testify in clear straightforward manner -don't exaggerate/embelish -talk to both sides -inform court of evidence if won't be disclosed -impartial -confident, respect, reasonable fee -report violations
3 parts to genotyping samples
- matrix file - internal size standard - allelic ladder
Acid phosphatase test
- presumptive test for semen - uses brentamine fast blue - phosphate cleaved from alphanaphthyl phosphate and then phosphate reacts with fast blue causing purple color change
Brady vs Maryland (1963)
- prosecution withheld evidence - violates due process
ABI 310 Genetic Analyzer
- single capillary around 50mm in diameter
DNA IQ system
- solid phase extraction with magnetic beads - DNA reversibly bound to magnetic beads when pH greater than 7.5 - magnet draws beads to side leaving impurities in solution - wash beads multiple times to clean DNA - elute DNA by heating
Acceleration
- the rate at which velocity changes over time - rate of speed up or slow down - describes magnitude and direction of velocity - F = MA - force = mass x acceleration
Calvin Goddard
- used a comparison microscope to determine if a particular gun fired a bullet - father of ballistics
Neutron
-A subatomic particle that has no charge and that is found in the nucleus of an atom - 1 neutron = 1.0087 amus
ASCLD/LAB
-American Society of Crime Laboratory Directors-Lab Accreditation Board " Accreditation through Inspection" - must achieve: - 50% desirable on least impact on work items - 75% important on items that don't affect work product or evidence integrity - 100% on items that affect work product and evidence integrity
CODIS Core Loci
-C2 = TPOX (simple) LEAST VARIATION -C3 = D3S1358 (compound) -C4 = FGA (compound) POLYMORPHIC -C5 = CSF1PO (simple) -C5 = D5S818 (simple) -C7 = D7S820 (simple) -C8 = D8S1179 (compound) -C11 = THO1 (simple, least polymorphic) -C12 = VWA (compound) -C13 = D13S317 (simple) -C16 = D16S539 (simple) -C18 = D18S51 (simple) POLYMORPHIC -C21 = D21S11 (complex) POLYMORPHIC
DNA in low pH
-DNA goes to organic phase rather than aqueous -depurination = purine (adenine or guanine) removed from deoxyribose sugar, OH group in its place
CE Steps
-Raw data generated -Baselining/Smoothing -Peak Detection -Peak Sizing -Genotyping -Filtering -Quality Assessment
anagen phase
-The initial growth phase during which the hair follicle actively produces hair. - 6 years
AmpliTaq Gold
-chemically active amino groups on lysine residue inativates taq -amino groups removed by hydrolysis at pH <7 -inactive until 95 degree C 10-11 min. -Tris Buffer - pH sensitive w/ temp fluctuation -Tris = pH 8.3 @ 25 degrees -Tris = pH 6.9 @ 95 degrees
ALUQUANT
-probes Alu repeats -probe-target hybridization = enzymatic reaction -light intensity compared to standard curve -0.1-50ng - DNA denatured, hybridized to upper primate probe - polymerase breaks down dsDNA and releases dNTPs - dNTP form ATP in relation to DNA - luciferase added which oxidizes ATP to produce light
Chelex Extraction
-produces ssDNA (only good for pcr based testing) -faster than organic, fewer steps, less chance sample to sample contamination -nucleases inactivated -ion exchange resin -ions chelate Mg2+ (inactivates nucleases)
DAB standard headings
-scope -definitions -QA program -organization and management -personnel -facilities -evidence control -validation -analytical procedures -equipment calibration -reports -review -proficiency -corrective action -audit -safety -outsourcing
1 pound (lb) to kg
0.454 kg
How much DNA is in a cell?
1 haploid cell has ~3pg of DNA
Crime Scene Lead Investigator
1. Determines boundaries 2. Determine perp entry and exit 3. Walk Through -overview/strategy for examination and documentation 4. Record Scene -Photo -Sketch -Notes
Crime Scene First Responder
1. Medical Assistance 2. Arrest perp 3. Preserve and Protect 4. exclude
CODIS loci
13/20 core loci
1 inch = ___ cm
2.54 cm
Capillary Electrophoresis (CE)
A method of separating DNA samples based on the rate of movement of each component through a gel-filled capillary while under the influence of an electric field
DNA 3' end
Carbon position where binding to next dNTP occurs
CODIS stands for
Combined DNA Index System
6 FAM loci (blue)
D8S1179 D21S11 D7S820 CSF1P0
DAB standards
DNA Advisory Board
DNA structure
DNA consists of two long chains of nucleotides twisted into a double helix and joined by hydrogen bonds between the complementary bases adenine and thymine or cytosine and guanine
5th Amendment
Due process, double jeopardy, self-incrimination, eminent domain.
DNA polymerase
Enzyme involved in DNA replication that joins individual nucleotides to produce a DNA molecule
EDTA
Ethylenediaminetetraacete. A calcium chelating (binding) agent that is used as an anticoagulant for laboratory blood specimens
direct evidence
Evidence that establishes the existence of a fact that is in question without relying on inference.
demonstrative evidence
Evidence that is not based on witness testimony but that demonstrates information relevant to the crime, such as maps, X-rays, and photographs; includes real evidence involved in the crime.
4th Amendment
Freedom from unreasonable searches and seizures
DNA replication
The process in which DNA makes a duplicate copy of itself.
Schedule I
This type of drug has no accepted medical use in the United States.
Developmental validation
Manufacturer - acquire test data and determine conditions for a new or novel method
CODIS (Combined DNA Index System)
National database of DNA profiles from forensic evidence, convicted offenders, certain arrestee samples, and missing persons
8th Amendment
No cruel or unusual punishment, no excessive bail
4x4 rule
No more than 4 alleles at any locus and no more than 4 loci with more than 2 alleles
3rd Amendment
No quartering of troops
DNA 5' end
Position in sugar where binding of previous dNTP occurred
10th Amendment
Powers of the States and People
14th Amendment
Prohibits states from abridging citizens privileges of immunities and rights to due process and equal protection under the law
Class Characteristics
Properties of evidence that can be associated only with a group and never with a single source.
9th Amendment
Protects rights not enumerated in the Constitution.
DNA quantification
Quantification determines the amount of human DNA present in an extract; A narrow concentration range is required for the polymerase chain reaction (PCR) - method of choice in most modern crime labs
6th Amendment
Right to a speedy trial Trial by jury Rights of the accused Right to Public trial Right to counsel
7th Amendment
Right to jury in civil trials.
2nd Amendment
Right to keep and bear arms
cholorplast
Site of photosynthesis
Edmund Locard
Stated that whenever 2 objects come into contact, there is always a transfer of material; strongly believed that a criminal could be connected to a crime by trace evidence collected at the crime scene
Schedule IV Controlled Substances
Substances in this schedule have a low potential for abuse relative to substances in Schedule III. Examples of Schedule IV substances include: alprazolam (Xanax), carisoprodol (Soma), clonazepam (Klonopin), clorazepate (Tranxene), diazepam (Valium), lorazepam (Ativan), midazolam (Versed), temazepam (Restoril), and triazolam (Halcion).
Schedule V Controlled Substances
Substances in this schedule have a low potential for abuse relative to substances listed in Schedule IV and consist primarily of preparations containing limited quantities of certain narcotics. Examples of Schedule V substances include: cough preparations containing not more than 200 milligrams of codeine per 100 milliliters or per 100 grams (Robitussin AC®, Phenergan with Codeine®), and ezogabine.
crime scene search patterns
Used to locate physical evidence at a crime scene; there are five patterns: spiral, strip/line, grid, zone/quadrant, and pie/wheel.
preservative
a substance that stops the growth of microorganisms in blood
buffy coat
a thin light colored layer of white blood cells and platelets than lie between a top layer of plasma and red blood cells when spun down
Schedule III
abuse may lead to moderate to low physical dependence or high psychological dependence. anabolic steroids and various compounds containing limited quantities of narcotic substances such as codeine are included
Depressants
drugs (such as alcohol, barbiturates, and opiates) that reduce neural activity and slow body functions
DNA strands
antiparallel
DNA in high pH
denature (reversible)
DNA
deoxyribonucleic acid, a self-replicating material present in nearly all living organisms as the main constituent of chromosomes. It is the carrier of genetic information.
Daubert v. Merrell Dow Pharmaceuticals
enormous change in law; burden shifts from scientists to judge and lawyers to decide the reliability of scientific evidence 3 requirements for scientific evidence: 1. Reliability 2. Fit 3. Scrutiny 5 Criteria for Reliability 1. Can it be tested 2. Publication, peer review 3. Known or potential rate of error 4. Standards governing the technique's operation 5. General acceptance
corpus delicti
facts proving that a crime has been committed; body of the victim in a murder case
Schedule II
high potential for abuse and may lead to physcial or psychological dependence but also has a currently accepted medical use in the US amphetamines cocaine methadone various opiates
Density
mass/volume
Aspermic
no sperm
atomic radius
one-half the distance between the nuclei of identical atoms that are bonded together
Counting method
p=x/n N = # of profiles x = # of times observed p = frequency of occurence
deductive reasoning
reasoning in which a conclusion is reached by stating a general principle and then applying that principle to a specific case (The sun rises every morning; therefore, the sun will rise on Tuesday morning.)
anticoagulant
slows coagulation and prevents new clots from forming
Duquenois-Levine Test
test for marijuana Purple
atomic number
the number of protons in the nucleus of an atom
Breech face
the rear part of a firearm barrel
Ballistics
the study of the dynamics or flight characteristics of projectiles
Dillie-Koppanyi Test
turns violet-blue in the presence of barbiturates
TaqMan system
uses a detector oligonucleotide that has a fluorescent reporter molecule at one end and a quencher molecule at the other end