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FORENSICS OF BLOOD BY : CYNDREKA LINDSEY CHEM-420111/20/2014.

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Presentation on theme: "FORENSICS OF BLOOD BY : CYNDREKA LINDSEY CHEM-420111/20/2014."— Presentation transcript:

1 FORENSICS OF BLOOD BY : CYNDREKA LINDSEY CHEM-420111/20/2014

2 OUTLINE BACKGROUND BACKGROUND SPATTER ANALYSIS SPATTER ANALYSIS BLOOD PATTERNS BLOOD PATTERNS COMMON TESTS COMMON TESTS WRITING ASSIGNMENT WRITING ASSIGNMENT QUESTIONS QUESTIONS

3 BACKGROUND BEFORE BLOOD ANALYSIS DETECTIVES HAD TO RELAY ON THEIR INSTINCTS AND CRIMINAL CONFESSIONS TO SOLVE A CRIME BEFORE BLOOD ANALYSIS DETECTIVES HAD TO RELAY ON THEIR INSTINCTS AND CRIMINAL CONFESSIONS TO SOLVE A CRIME SEROLOGY: THE EFFECTS OF SERUMS AND THE ANALYSIS OF ITS PROPERTIES SEROLOGY: THE EFFECTS OF SERUMS AND THE ANALYSIS OF ITS PROPERTIES BLOOD, SEMEN, SWEAT, SALIVA BLOOD, SEMEN, SWEAT, SALIVA WHEN STRUCK WITH A CERTAIN AMOUNT OF FORCE BODIES LEAK OR SPRAY BLOOD AND THE BLOOD IN FLIGHT TENDS TO BE UNAFFECTED BY WHEN STRUCK WITH A CERTAIN AMOUNT OF FORCE BODIES LEAK OR SPRAY BLOOD AND THE BLOOD IN FLIGHT TENDS TO BE UNAFFECTED BY TEMPERATURE, HUMIDITY, OR ATMOSPHERIC PRESSURE. TEMPERATURE, HUMIDITY, OR ATMOSPHERIC PRESSURE. BLOOD EVIDENCE IS FOUND IN CRIMES OF VIOLENCE : BLOOD EVIDENCE IS FOUND IN CRIMES OF VIOLENCE : HOMICIDE, ASSAULT, AND SEXUAL ASSAULT. HOMICIDE, ASSAULT, AND SEXUAL ASSAULT. IT MAY BE IN THE FORM OF FRESH LIQUID, COAGULATED, DRIED, OR AS A SMALL DROP OR STAIN, AND EACH FORM INVOLVES A DIFFERENT METHOD OF PRESERVATION AND COLLECTION. IT MAY BE IN THE FORM OF FRESH LIQUID, COAGULATED, DRIED, OR AS A SMALL DROP OR STAIN, AND EACH FORM INVOLVES A DIFFERENT METHOD OF PRESERVATION AND COLLECTION.

4 BLOOD SPATTER PATTERNS Transfer Swipe Pattern: Movement from stained to unstained surface Transfer Wipe Pattern: Moves through an existing stained surface Spatter Pattern: Created by force and travels through air before hitting surface

5 BLOOD SPATTER ANALYSIS Low Velocity Blood Spatter: Blood that falls at the speed or force of normal gravity Medium Velocity Blood Spatter: Produced with more energy than the force of normal gravity High Velocity Blood Spatter: The force should be greater than 100 feet per second (high speed collisions)

6 COMMON TESTS FOR BLOOD…. COMMON TESTS FOR BLOOD….

7 BENZIDINE TEST Benzidine is prepared from nitrobenzene in a two step process [5,5] Sigmatropic Rearrangement

8 LEUCOMALACHITE GREEN (LMG) The condensation of benzaldehyde and dimethylaniline to give Leucomalachite gree is how Malachite green is prepared

9 KASTLE-MEYER TEST (KM) A potential blood sample is treated with phenolphthalein and it turns pink due to an oxidation reaction

10 HEMASTIX TEST The test is based on the peroxidase-like activity of blood which has the ability to cleave oxygen molecules from H2O2 and catalyze the reaction from the reduced colorless form of 3,3’,5,5’-tetramethylbenzidine to the oxidized colored form

11 LUMINOL TEST An oxidizing agent, such as blood, catalyzes the oxidation of luminol by hydrogen peroxide in a basic solution and the light emitted in the luminol reaction is the result of a positive test.

12 WRITING ASSIGNMENT…. RECREATION OF A FAMOUS BRUTAL CRIME SCENE (OJ SIMPSON MURDER CASE) RECREATION OF A FAMOUS BRUTAL CRIME SCENE (OJ SIMPSON MURDER CASE) WILL BE A VISUAL DISPLAY ON THE BLOOD PATTERN AND SPATTER IN THREE DIFFERENT SCENES WILL BE A VISUAL DISPLAY ON THE BLOOD PATTERN AND SPATTER IN THREE DIFFERENT SCENES FROM MY DISPLAY THE CLASS SHOULD BE ABLE TO IDENTIFY (IF ANY): FROM MY DISPLAY THE CLASS SHOULD BE ABLE TO IDENTIFY (IF ANY): WHAT PRESUMPTIVE TEST TO USE? WHAT PRESUMPTIVE TEST TO USE? WHAT IS THE PATTERN OF THE BLOOD? WHAT IS THE PATTERN OF THE BLOOD? WHAT IS THE SPATTER VELOCITY OF THE BLOOD? WHAT IS THE SPATTER VELOCITY OF THE BLOOD? WHAT OBJECTS COULD HAVE BEEN USED IN THIS CRIME? WHAT OBJECTS COULD HAVE BEEN USED IN THIS CRIME? WAS THERE ANY CLEAN UP OF THE BLOOD? WAS THERE ANY CLEAN UP OF THE BLOOD?

13 REFERENCES BEVEL, TOM AND GARDNER, ROSS M. BLOODSTAIN PATTERN ANALYSIS, 2ND ED. CRC PRESS: BOCA RATON, FL, 2002. BEVEL, TOM AND GARDNER, ROSS M. BLOODSTAIN PATTERN ANALYSIS, 2ND ED. CRC PRESS: BOCA RATON, FL, 2002. JAMES, STUART H. AND NORDBY, JON J. FORENSIC SCIENCE: AN INTRODUCTION TO SCIENTIFIC AND INVESTIGATIVE TECHNIQUES, 2ND ED. CRC PRESS: BOCA RATON, FL, 2005. JAMES, STUART H. AND NORDBY, JON J. FORENSIC SCIENCE: AN INTRODUCTION TO SCIENTIFIC AND INVESTIGATIVE TECHNIQUES, 2ND ED. CRC PRESS: BOCA RATON, FL, 2005. SAFERSTEIN, RICHARD. CRIMINALISTICS: AN INTRODUCTION TO FORENSIC SCIENCE. PEARSON PRENTICE HALL: SADDLE RIVER, NJ, 2004 SAFERSTEIN, RICHARD. CRIMINALISTICS: AN INTRODUCTION TO FORENSIC SCIENCE. PEARSON PRENTICE HALL: SADDLE RIVER, NJ, 2004 BLOOD TYPE HTTP://EN.WIKIPEDIA.ORG/WIKI/BLOOD_TYPE BLOOD TYPE HTTP://EN.WIKIPEDIA.ORG/WIKI/BLOOD_TYPE BLOOD PLASMA HTTP://EN.WIKIPEDIA.ORG/WIKI/BLOOD_PLASMA BLOOD PLASMA HTTP://EN.WIKIPEDIA.ORG/WIKI/BLOOD_PLASMA FORENSIC INVESTIGATIONS—BLOOD SPATTER: ALL ABOUT BLOOD WWW.CLT.UWA.EDU.AU/__DATA/PAGE/112508/ FSB04.PDF FORENSIC INVESTIGATIONS—BLOOD SPATTER: ALL ABOUT BLOOD WWW.CLT.UWA.EDU.AU/__DATA/PAGE/112508/ FSB04.PDF WWW.CLT.UWA.EDU.AU/__DATA/PAGE/112508/

14 QUESTIONS?


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