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1. IMMEDIATE - Of somatic death 2. EARLY - Of molecular death 3. LATE - Of decomposition POST MORTEM CHANGES

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1. IMMEDIATE- Of somatic death2. EARLY- Of molecular death3. LATE- Of decomposition

POST MORTEM CHANGES

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IMMEDAITE SIGNS:

1. Insensibility and loss of movements – with voluntary power.

2. Cessation of respiration

3. Cessation of circulation

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EARLY SIGNS OF DEATH:

1. Pallor and loss of elasticity of skin2. Changes in the eyes3. Primary flaccidity of muscles4. Cooling of body5. Post mortem lividity6. Rigor mortis

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LATE SIGNS:

1. Decomposition

2. Adipocere formation

3. Mummification

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CHANGES IN THE EYES

1. loss of corneal reflex2. opacity of cornea3. flaccidity of eye balls 4. Changes in retinal vessels5. Pupils6. Chemical changes in vitreous humour

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CHANGES IN THE EYES:1. OPACITY OF THE CORNEA-- Due to drying in open eyelids.- In closed eyes occurs in 2 hours.-May occur even before death in cholera & wasting diseases.- “ Tache Noirs”- At each side of iris , on sclera, triangular in shape, yellowish brown in colour occurs in few hours due to deposition of film of cell debris and mucus, if the eyelids are left open after death.

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2. CORNEAL REFLEX 3.FLACCIDITY OF EYEBALLS - A sign of death , but not a reliable one as even before death , in all cases of deep insensibility it may be absent

-- Due to fall in intra ocular tension within minutes of death the eyeballs go flaccid.- IOT can be measures with TONOMETER.- Normal value 15-25 mg - Soon after death- 12 mg-Half hour- 3 mg- 2 hours – 0 ( zero )

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4. CHANGES IN PUPILS:-Normal size is 2-5 mm, < 2 mm – constricted, > 5 mm dilated-Soon after death, due to relaxation of muscles of iris pupils dilate and with onset of rigor mortis they come back to same position due to constriction- NOT A UNIVERSALLY ACCEPTABLE THEORY because in rigor mortis there is only stiffening and no shortening.- Till 1 hour( molecular death it may dilate with atropine but don’t react to strong light.

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5. Retinal vessels: Show fragmentation or segmentation of blood column in retinal vessels within few minutes and last for 1-2 hours.- Can be seen with ophthalmoscope.- It is dye to loss of blood pressure following loss of circulation.6. Chemical changes: Post mortem chemical anlysis of vitreous humor show a steady rise on Potassium levels in decomposition pattern ( low Sodium and chloride and elevated Potassium) – Due to cell disintegration of cell.Formula suggested by Sturner-PMI= 7.14 X K concentration( m.Eq./ L) - 39.1

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4.COOLING OF BODY:( ALGOR MORTIS): Heat loss is by -> By CONVECTION, CONDUCTION, EVAPORATIONFACTORS AFFECTING HEAT LOSS:

1. Body weight and surface area- rapid in extremes of age2.Proportion of fat- slow in obese persons and vice versa- fat a bad conductor of heat 3. Covering layers around body4. Difference between body and ambient temperature- rate is more when the difference is more.5. Environment- well ventilated place, moisture= rapid coolingIn India rate is 0.5 to 0.7 per hour.

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FORMULA: Time in hours = Normal Body temperature – rectal temperature Rate of temperature fall per hour

For example,Normal Body temperature is 37.2 degree CelsiusRectal Temperature is 30.2degree Celsius ,Rate of fall is 0.5TSD= 37.2 – 30.2 = 7 / 0.5 = 14 hours

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POST MORTEM CALORICITY: raised temperature after death.

Causes: 1.Thermo-regulatory disturbance- sunstroke, air embolism 2. Muscular over activity- tetanus, strychnine poisoning 3. Bacterial activity- Cholera , septicemia

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5.POST MORTEM LIVIDTY: ( PM HYPOSTASIS, PM STAINING, LIVOR MORTIS, CADAVER LIVIDITY)

DEFINITION: It is purplish red discolouration on the surface of dependent parts of body due to capilo-venous distension after death.

MECHANISM: Due to accumulation of blood in toneless distended blood vessels. It reflects the colour of Hb.

.

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WHAT MEANS DEPENDENT PARTS?

POSITION DEPENDENT PARTS

1. Supine - Back of shoulders, chest, buttocks, thigh2. Prone – Face, front of chest& abdomen, thighs3. Standing- Both hands, male genitals, soles4. Kneeling- Both knee, front of legs, toes.

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TIME OF APPAEARENCE AND DISAPPEARENCE

Beginning- 30 minutesConfluence patches- 1-4 hoursFixation- 4-12 hours( due to coagulation)Disappearance- about 24 hours--> Press the thumb on stained area if it fades and reappears on withdrawal – not fixed.--> No change on pressure by thumb- fixed.

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CAUSES OF EARLY ONSET OF POST MORTEM LIVIDITY:

Persons who die from conditions in which there is circulatory failure which permits some ante mortem pooling of blood in superficial vessels- cholera, typhus fever,tuberculosis, uremia and prolonged illness.

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CAUSES OF DELAYED ONSET:

1. Anaemia2.large amount of IV fluids3. Massive blood loss4. Lobar pneumonia( rapid clotting)In dark complexed person it may be difficult to appreciate in early stage.

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Interpretation of colour of lividity:

1. Deep purple- in asphyxia due to increase in amount of reduced Hb.

2. Bright red- in cyanide poisoning due to cyan meth haemoglobin

3. Pink- in cabon monoxide poisoning due to carboxy Hb.

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4. Chocolate brown – in Potassium chlorate poisoning due to methhemoglobin.

5. Reddih brown – in Nitrite poisoning .

6. Yellow or dark brown – in Phosphorous poisoning.

7. Pale or less prominent- anemia, pneumonia.

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DIFFERENCE BETWEEN :LIVIDITY & CONGESTION 1. Position- dependent parts only irrespective of

position2. Distribution- irregular Uniform3.Inflammation- absent present4. Hollow viscera like stomach:Alternate areas of staining Diffuse.

( On stretching of hollow viscus)

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DIFFERENCE BETWEENLIVIDTY & BRUISE

1. Margins- sharply defined ill defined2. Surface- Not swollen oedematous3. Colour change- no change Changes with age4.Pressure- Blanches till not fixed No chage5. On cut section- no extravasation extravasation of blood

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MEDICOLEGAL IMPORTANCE OF POST MORTEM LIVIDITY:

1. It is a reliable sign of death.2. Indicates body position at death and any alteration in body position later on.3.Peculiar colour may indicate particular poisoning.4. May indicate time since death – fixed or not.

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6. CHANGES IN MUSCLES:

1. STAGE OF PRIMARY FLACIDITY: - Generalised relaxation lasting up to 2-3 hours after death2. STAGE OF RIGOR MORTIS:- Charecterised by stiffness3. STAGE OF SECONDARY FLACIDITY:-With disappearance of rigor mortis , muscles again becomes flaccid.

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RIGOR MORTIS / CADEVERIC RIGIDITY:

DEIFNITION:It is a state of post mortem stiffening in both voluntary and involuntary muscles following the period of primary flaccidityMECHANISM: Each muscle comprises of myofibril – made up of proteins- Actin and myosisin in interdigiting arrays. ATP is required to maintain relaxation of muscle which is absorbed by muscle in state of relaxation and utilised for contraction. After death , some amount of ATP

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Is available till molecular death. But after that as it not available to maintain relaxation the acto-myosin complex develops stiffness and produces muscular rigidity which disappears with autolysis of muscle fibres after some duration.SEQUENCE: Proximo-distal progression and disappearance in same sequence.

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TIME OF ONSET, PERSISTANCE AND DIAPPEARENCE:

SEASON WINTER SUMMER AVERAGE0NSET Slow- 2-6 rapid – 2-3 2-6 hrsCOMPLETION 6-24 3-18 6-12 PERISTANT 24-48 18-36 12-24DISAPEARENCE 48-72 36-48 24-36

RULE: When rigor mortis sets in early, it remains for shorter time and disappears early. When it sets in late, remains for longer time and disappears slowly.

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FACTORS AFFECTING ONSET, DURATION AND DISAPPEARENCE OF RIGOR MORTIS:

1. AGE: Extremes of age earlier & for shorter duration. 2. ENVIRONMENTAL TEMPERATURE:Slow- in cold , rapid in hot environment3. MUSCULAR STATE:Rapid in thin body, slow in more muscular body.4. CAUSE OF DEATH: EARLTY LATE Cholera, typhoid, TB, cancer, nephritis Pneumonia, asphyxia CO, CO2, Arsenic

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HOW RIGOR MORTIS IS TESTED?- By gen tally bending various joints: Perception Interpretation- Free movement Not present- Moves with little force Present in moderate form- Moves with more force Present in strong formNOT present in a part tested - Not appeared or disappeared.If distal parts show rigidity – Developed & disappeared.If proximal parts show rigidity – Not developed.

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DIFFERENCE BETWEEN RIGOR MORTIS & HEAT STIFFENING

1. Cause: Loss of AT.P. Temperature > 652. Onset: In sequence Rapid and diffuse3. Mechanical: will revert rigidity rupture of muscles extension4.Result: Actin-myosin complex coagulation of proteins5.Disappearance: in sequence, Uniform with onset at various duration of putrefaction

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DIFFERENCE BETWEEN RIGOR MORTIS AND COLD STIFFENING

1.Cause: ATP loss temperature < 3-42. History: Non specific ice caves, glacier3. Body fluids : Liquid frozen4. Disappearance: sequence & on thawing it goes duration & RM appearers.

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CADAVERIC SPASM:DEFINITION:

The group of muscles that were contracted just before death, become stiff and rigid without passing into stage of primary relaxation.MECHANISM: Obscure. Probably, due to over activity just before death ATP gets exhausted and muscles pass into state of rigidity.CIRCUMSTANCES: excitement, cerebral hemorrhage,

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fear, injury to nervous system, cranial gunshots, convulsant poisons, efforts by a submerging victim.

MEDICO LEGAL ASPECTS:1. Affects only a group of muscles.2.A drowning victim may firmly grasp weeds, grass . 3.In suicide by cranial gunshot wound leading to suddendeath the weapon may be grasped in the hand.4.Muscles does not develop rigor mortis and rigidity disappears with putrefaction.

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TSD- 0 6 12 18 24 30 3 6 42 48 54

37

Temperature

decom

lividity

Rigor mortiscooling

CHART showing major changes to estimate time since death

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LATE CHANGES:DECOMPOSTION-- Result of two processes- Autolysis and putrefactionAUTOLYSIS: ( Auto= self, lysis= break down)After death, permeability of cell membrane increases which allows release of various enzymes in cytoplasm:-- Proteolytic, glycolytic and lipolytic action without bacterial action, temperature affects its rate- slow by cold & vice versaEARLY IN:Parenchymatous tissue, brain and glandular tissue.Leads to liquefaction necrosis of tissue.

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PUTREFACTION:By Fauna- out side body & inside body flies, maggots, microbes anaerobic flora- intestines-- Produced by bacterial enzymes, anaerobic variety and also from fungi. Cl. Welchi is the main causative organism which causes:

1. Haemolysis2. Liquefaction of blood clots3. Disintegration of tissue4 Gas formation

-- Other microbes: Streptococi, Staphylococi, B. Proteus, B. Coli

-- They spread through vessels as proteins and carbohydrate act as culture media for the.

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ENZYMES AND THEIR ROLE IN PUTREFACTION:Lecithinase produced by Cl Welchi hydrolyses the lecithin of the cell membrane.

FACTORS FAVOURING BACTERIAL ACTIVITY:1. loss of protective mechanism2. Open skin wounds3. Fall in oxygen and rise in hydrogen4. Fluidity of blood and carbohyrates & proteins in blood.5. Pre existing infection before death

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CHARECTERISTIC FEATURES OF PUTREFACTION:1. COLOUR CHANGE2. EVOLUTION OF GASES3. LIQUEFACTION

1. COLOUR CHANGE: In the early stage, due to diffusion of Hb through the vessels the tissue shows red or brown colour. In the tissue Hb derivatives combine with Sulphur containing compounds forming sulphmeth haemoglobin and change the colour into greenish black. As the caecum is the most superficial part of intestine this change is perceived first there in about 12-18 hours in summer and 1-2 days in winter.This discolouration further spreads over entire abdomen, genitals, chest, neck, face arms and leg.

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MARBLING EFFECT OR APPEARENCE:

The putrefactive bacteria spread more easily in fluid and tend to colonise venous stem. The superficial veins get stained reddish puple due to haemolysis of red cells . This stained vascular channels against back ground of pale dermis give the surface the “ MARBLING EFFECT”. It becomes prominent in 36-48 hours after death.

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MARBLING EFFECT- Prominent toneless superficial veins filled with hemolysing blood against pale dermis.

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The clotted blood becomes fluid and which cause disappearance of post mortem lividity . Later this colour change spread all over the body.

2. EVOLUTION OF GASES: The complex proteins and carbohydrate compound s disintegrate and produce gases life: AMONIA, CARBON MONOXIDE, CARBON DIOXIDE, HYDROGEN SULPHIDE, PHOSPHORATED HYDROGEN, METHANE, MERCAPTANE.Collection of these gases in loops of intestine leads to distension of abdomen,So, on opening the abdominal cavity these gases come out with force and hissing sound.

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This gases entrapped in closed area go on accumulating and lead to :

1. Protrusion of eye balls2. Swollen appearance of face3. Oozing out of fluids from orifices like nose mouth, ear, anus and vagina.4. Post mortem blisters due to separation of layers of epidermis.5. Expulsion of fetus in pregnant woman.6. Protrusion of rectum through anus.

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7. Post mortem blister formation due to separation of layers of epidermis..8. Loosening of hair, teeth and nails.9. Protrusion of cavity contents from open wounds.10. Pealing of cuticle leading to DEGLOVING & DESOCKING OF SKIN OF HANDS AND FEET RESPECTIVELY.-- Post mortem luminescence ( shining look) is due to light producing organisms like:PHOTOBACTERIUM FISCHERI, ARMILARIA MALLEA( fungi)-- Bodies submerged under water surface due to gases.

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A DECOMPOSING DEAD BODY- Swollen appearance,pealing of epidermis ,brown discolouration and blisters.,

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3.LIQUEFACTION ( & SKELETONIZATION)- Colliquative putrefaction starts in 5-10 days and all soft tissue start loosing their normal architecture. The concerned cavity gets filled with liquefied tissue materials.

SEQUENCE OF PUTREFACTION IN ORGANS1. Larynx and trachea2. Stomach, intestine and spleen DEPENDS ON TISSUE3. Liver and lungs COMPOSITION- BLOOD,4. Brain FIBROUS , CARTILAGENOUS4. heart FLUID RICHNESS5. Kidney, bladder6. Prostate , uterus7. Skin, muscles and bones.

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SKELETONISATION: The time required for completion depends mainly on factors like post mortem eating by

carnivorous animals like jackals, dogs, vultures etc. They eat away soft tissues and produce “ Gnawing effect”which are tissue defects devoid of hemorrhage.The bones decay with loss of proteins and ultimatelycomplete conversion of all ORGANIC materials intoINORGANIC materials – in “panch mahabhut”

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FACTORS AFFECTING RATE OF PUTREFACTION:1. TEMPERTAURE2. MOISTURE3. AIR

4. CLOTHINGSAND COVERINGS5. AGE 6. BUILT7.CAUSE OF DEATH8. DEGREE OF MUTILATION:9. CASPER’S DICTUM: Rate of putrefaction:

Above earth Under water Under earth 8 2 1

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MUMMIFICATION: It is a modification of process ofputrefaction in which shrivelling and drying of dead body occurs due to dehydration of water.

FACTORS NECESSARY:1. Absence of moisture in the air2. Persistent action of dry air.APPWARENCE:- Shrunken skin, dry, leathery, fragile and rusty brown in colour-- skin adheres tightly to bony prominences-- involves exposed parts first, later even internal organs

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CHARECTERISTICS:-- Body is odour free,-- 3 months to 1 year required for completion-- Features and wounds are well preserved.CIRCUMSTANCE:- Bodies trapped in closed room or cupboard, graveyard-- Death due to chronic arsenic or antimony poisoning- dehydration before death..MEDICOLEGAL IMPORTANCE:1. Identity can be established as features are well preserved..2. Cause of death can be concluded as the wounds are preserved.3. Gives idea about time since death.ARTIFICIAL MUMMIFICATION - EMBAMMING.

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ADIPOCERA ( SAPONIFICATION): is a modification of putrefaction in which the fatty tissue are converted intoinsoluble soap - adipocere.

CIRCUMSATNCES: - Damp and warm environment.- There is gradual hydrolysis and hydrogenation of fats intoPALMITIC ACIDOLEIC ACID --> combines with calcium and ---> forms insolubleSTEARIC ACID ammonium ions soapsHYDROXY STEARIC ACID

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BACTERIAL ACTION: Cl. Pefringens produces Lecithinase which leads to hydrolysis and hydrogenation. Later on with saponification the environment becomes acidic which prevents bacterial action and hence putrefaction gets arrested and does not progress.

PROPERTIES: - Strong amonical smell in early stage followed bt sweetish offensive smell- Fresh adipocere is soft, moist, whitish and translucent.- Old adepocere is dry , hard, cracked yellowish in colour and brittle.- Insoluble in water but dissolves in ether and alcohol.- It is inflammable and burns with yellow flame.

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TIME REQUIRED :--3-4 weeks in summer in temperate countries-- On average 3-6 months-- May persist for years if left undisturbed.

DISTRIBUTION:-- Fat depots – superficial to deep in direction.-- Face, female breast, buttocks, pericardial- mesentric – pancreas ets

MEDICO LEGAL APPLICATION:1. Help in establishing identity as features are preserved.2. May help in ascertaining cause of death from wounds.3. Gives idea about time since death.

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OTHER PARAMETERS TO DICIDE TIME SINCE DEATH:

1. ENTOMOLOGY OF CADAVER:( FORENSIC ENTOMOLOGY)Flies --> eggs --> larvae or maggots --> pupae--> adult fly few minutes + 8-12 hr + 4-5 days + 3-5 daysCOMMON SITES: natural orifices and wounds.ROLE: Maggots produce proteolytic enzymes which help in destruction of tissue. They crawl into deeper parts by making furrows and further expose deeper parts to air.APPLICATION: Time since death by stage and number of generations.

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2. CONDITION OF STOMACH CONTENTS:Examination of stomach contents can give an idea about time of last meal taken or after how much time after consuming food the victim died. Normal gastric emptying time = 2 hours.FACTORS TO BE CONSIDERED FOR SUCH OPINION:

1. Age2. Amount of food3. Type of food- solid or liquid4. Contents of food- carbohydrate / fats / proteins5. Vomiting or gastric lavage just before death6. Expulsion of contents due to putrefaction.7. Seasonal variation and GIT disease

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3. POST MORTEM CHEMISTRY:Samples : Blood, urnine , CSF, peritoneat / pericardial fluid, VITROUS HUMOUR.TYPES:Electrolytes mainly – almost all tests.

Pattern Na C l K UreaDehydration - +++ +++ N +Uremic - N N N +++Low salt - -- - -- - -- NDecomposition - ---- -- ++++ N

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EXHUMATION: Lawful digging out of already buried body fromgrave yard. NO TIME LIMIT FOR EXHUMATION IN INDIA. AUTHORITY: Order of executive magistrate.WHY DEAD BODY IS EXHUMED?

1. Suspicious crime, need of further investigations.2. Claims and compensation matters3. Unlawful burial.

PROCEDURE:- EXECUTIVE MAGISTRATE + POLICE + DOCTOR - Identification of g graveyard and grave- Conducted in day light.

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- Sample of soil to be collected : ABOVE , BELOW, RIGHT, LEFT, FRONT& BACK- Identification of coffin- Identification of body- Care in lifting & transportation- so a s to avoid damage.DISINFECTANTS SHALL NOT BE SPRINKLED.

SECOND AUTOPSY:- Documents of first autopsy- If possible the first autopsy surgeon sholud be called upon.- Discrepancies between two- Condition of body, time since death, time between two autopsies shall be considered before giving a contradicting opinion.

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EXAMINATION OF SKELETONISED AND MUTILATED BODIES:

1. Whether Human or animal? - Comparative Anatomy, Precipitin test

2. Belongs to one or more than one individual?3. Sex, age, stature and other identity points4. Manner of separation:NATURAL, CUT, SERRATED, LACERTED5. cause of death6. Time since death

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TIME SINCE DEATH AND RADIO ACTIVE CARBONANALYSIS: The C 14 levels are constant during life of an individuals and starts reducingafter death where it reaches to half level after 5600 years. Not helpful in routine medico legal cases but only for Archaeological purposes.

FOR MEDICO LEGAL PURPOSE:NitrogenAmino acidsPro linesFluorescenceBenzidineGel diffusion 0 10 20 30 40 50 100 200 400 800

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PRESUMPTION OF DEATH:The question may arise in following cases:1. Insurance claims2. Inheritance of property3. Resolving partnerships--> S.107 &108 of IEA : If a person is proved to have been alive within 30 years, the legal presumption is that he is still alive, unless it is proves that the person has not been heard of for 7 years by those who would normally have heard of him.

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PRESUMPTION OF SUVIVOR SHIP:-- When more than one natural heirs of each other die in a common event. i.e. Air-crash, shipwreck, earthquake etc.

Consequences : If X has made will of his property to Y instead of heirs of X. Now , if X survived Y, his property will go to heirs of X and not to heirs of Y. Because Y died during lifetime of X, then he has lost his claim under will .Following factors shall be considered to decide who survived whom:1 Post mortem changes.2. Nature of injuries.

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3. Age4. Sex5. History of previous major illness6. Cause of death.--- - - - - - - - - - - XOX- - - - - - - - XOX - - - - - - - - - - - -

CONTD.----