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Bloodstain Tutorial

Bloodstain Tutorial
The success or failure of any criminal investigation often depends on the recognition of physical evidence left at a crime scene and the proper analysis of that evidence. Crime scenes that involve bloodshed often contain a wealth of information in the form of bloodstains. The pattern, size, shape, and the location of such stains may be very useful in the reconstruction of the events that occurred. William G. Bloodstain Pattern Analysis: The examination of the shapes, locations and distribution patterns of bloodstains in order to provide an interpretation of the physical events by which they were created that is based on the premise that all bloodstains and bloodstain patterns are characteristic of the forces that have created them. The interpretation of bloodstain patterns found at the scene or on exhibits such as the clothing of the principles of the occurrence can be used to: Properties of Blood: A blood loss of 1.5 liters internally/externally is required to cause incapacitation. Related:  Forensic ScienceCSI

The Bloody Truth: How to Interpret Blood Spatters | Wired Magazine Photo: Rod Englert Some people can’t stand the sight of blood. Rod Englert is not one of those people. A detective with 45 years of investigative experience, Englert analyzes the Jackson Pollock-like spatters of hemoglobin and plasma at crime scenes. 1 Angular If the victim was on the move, drops hit at an angle. 2 High Velocity Misty, diffuse spatter is created by external force greater than 100 feet per second — which usually means a gunshot, an explosion, or (seriously) a sneeze. 3 Hair Impact A traumatic impact between head and surface tends to leave a stain with feathered edges, like someone squished a loaded paintbrush against the wall. 4 Hair Swipe If the smear fades out in one direction, the head was likely bloody before contact. 5 Fabric Swipe More fluid than hair swipes, these stains sometimes display the imprint of the bloodied clothing.

How Bloodstain Pattern Analysis Works If you're flipping channels one day and come upon a crime scene as depicted on one of the many TV shows that focus on forensic science, such as "CSI" or "Dexter," you might notice something strange. Among the technicians dusting for fingerprints and collecting hair fibers at the murder scene, you spot an array of red strings running from the floor, the wall, the table and the sofa. All of the strings meet at nearly the same point. Suddenly, an investigator begins recounting aspects of the crime: When it happened, where the assault took place in the room, what kind of weapon the perpetrator used and how close to the victim the assailant stood. The strings themselves aren't important. Of course, analyzing blood spatter isn't as simple as fictional bloodstain pattern analysts like Dexter Morgan make it appear. Let's start with the basics of bloodstain pattern analysis — for example, what blood spatters can reveal (and what they can't).

The History of Fingerprints Fingerprints offer a reliable means of personal identification. That is the essential explanation for fingerprints having replaced other methods of establishing the identities of persons reluctant to admit previous arrests. 1 The science of fingerprint identification 5 stands out among all other forensic sciences for many reasons, including the following: Other visible human characteristics, such as facial features, tend to change considerably with age, but fingerprints are relatively persistent. In earlier civilizations, branding or maiming were used to mark persons as criminals. Before the mid-1800s, law enforcement officers with extraordinary visual memories, so-called "camera eyes," identified previously arrested offenders by sight alone. Around 1870, French anthropologist Alphonse Bertillon devised a system to measure and record the dimensions of certain bony parts of the body. Upon investigation, there were indeed two men who looked very similar. AD 1400s - Persia 1600s 1685 - Bidloo

Test your bloodstain analysis skills - Image 1 Cookies on the New Scientist website close Our website uses cookies, which are small text files that are widely used in order to make websites work more effectively. Find out about our cookies and how to change them Test your bloodstain analysis skills 00:00 25 February 2009 Bloodstain analysts claim to be able to identify how a bloodstain was created simply by looking at it. Next Image 1 of 21 Question 1 How was this bloodstain created? All Galleries| Blood Types: ABO and Rh (with donuts and sprinkles!) The man who cleans up blood after murders Image copyright Bénédicte Desrus / Alamy Mexico has one of the highest murder rates in the world, but who cleans up the blood at the crime scene when the police and investigators have left? Donovan Tavera is Mexico's first forensic cleaner. What happens to the blood after a murder? The first time I saw a dead body was when I was 12 years old. As well as us bystanders there were police officers and investigators. I asked her: "Who cleans the blood after a murder?" When my father came home from work I asked him too: "What happens to the blood after a murder? That was when I decided to find out for myself. A murder isn't the same as an accident - in a murder there is a lot of blood. When I was about 17 I started experimenting. And that's how I became a forensic cleaner. Over the years I have invented more than 300 different formulas to clean up blood. Before I come I ask what happened, and where the corpse is. Find out more I am the last person to visit the scene of the crime.

Collection and Preservation of Blood Evidence from Crime Scenes -- Crime Scene Investigator Network Printer Friendly Collection and Preservation ofBlood Evidence from Crime Scenes by George Schiro Forensic Scientist Louisiana State Police Crime Laboratory Preliminary Considerations Since blood evidence associated with a crime can provide information that may solve the case, it is essential to correctly document, collect, and preserve this type of evidence. Communication is the key to effectively processing blood evidence. The technological state of blood evidence analysis has rapidly advanced in the last 20 years. ln the early seventies, most crime labs relied upon the ABO blood grouping system to characterize bloodstains. Currently, bloodstain analysis falls into three broad categories. Conventional serological analysis Analysis of the proteins, enzymes, and antigens present in the blood. Restriction Fragment Length Polymorphism (RFLP) DNA analysis Direct analysis of certain DNA sequences present in the white blood cells. Polymerase Chain Reaction (PCR) DNA analysis

Violence Formula: Analyzing TV, Video and Movies Violence is the foundation of many films, TV movies, and action series. In fact, violence is often synonymous with "action." Because screenwriters, directors and producers use violence often and in many ways, how do we begin to recognize the distinctions in media violence? 1. Without the violence, there would be no story. Take a look at your daily TV listings. TV action series demonstrate a similar inclination for violence driving the story. TV and film plots begin with violence, and impending conflict continues to drive the story. 2. TV violence doesn't bleed. Perhaps the most chilling aspect of the media's portrayal of violence is that when people are killed, they simply disappear. 3. Media violence takes place in a world of good and bad. to be enlisted very quickly. As a result, TV and film criminals are reduced to caricatures. Bad guys have to be really bad otherwise good guys wouldn't be justified in clobbering them. How to Teach the Violence Formula to Others Violent Storylines

List of digital forensics tools During the 1980s, most digital forensic investigations consisted of "live analysis", examining digital media directly using non-specialist tools. In the 1990s, several freeware and other proprietary tools (both hardware and software) were created to allow investigations to take place without modifying media. This first set of tools mainly focused on computer forensics, although in recent years similar tools have evolved for the field of mobile device forensics.[1] Computer forensics[edit] Memory forensics[edit] Memory forensics tools are used to acquire and/or analyze a computer's volatile memory (RAM). Mobile device forensics[edit] Mobile forensics tools tend to consist of both a hardware and software component. Other[edit] References[edit]

Blood Types | American Red Cross Although all blood is made of the same basic elements, not all blood is alike. In fact, there are eight different common blood types, which are determined by the presence or absence of certain antigens – substances that can trigger an immune response if they are foreign to the body. Since some antigens can trigger a patient's immune system to attack the transfused blood, safe blood transfusions depend on careful blood typing and cross-matching. The ABO Blood Group System There are four major blood groups determined by the presence or absence of two antigens – A and B – on the surface of red blood cells: Group A – has only the A antigen on red cells (and B antibody in the plasma)Group B – has only the B antigen on red cells (and A antibody in the plasma)Group AB – has both A and B antigens on red cells (but neither A nor B antibody in the plasma)Group O – has neither A nor B antigens on red cells (but both A and B antibody are in the plasma) Blood Types and the Population It’s inherited.

Explosions - Chemistry Encyclopedia - reaction, examples, gas, equation, molecule, mass, atom Photo by: Ramzi Hachicho An explosion is a sudden, violent change of potential energy to work, which transfers to its surroundings in the form of a rapidly moving rise in pressure called a blast wave or shock wave. The shock wave can cause substantial damage. Potential energy may exist in either of three forms before an explosion occurs: nuclear , chemical, or physical. Generally, nuclear explosions are much larger and more destructive than chemical or physical explosions. Nuclear Explosions Nuclear explosions may be caused by either fusion or fission reactions. In a fission reaction, a single large atom, such as uranium, is bombarded with neutrons, causing the nucleus of the atom to split into two smaller nuclei and several neutrons. A nuclear explosion at sea. Both fusion and fission reactions can be used in bombs. Chemical Explosions Chemical explosions may be either decomposition or combination reactions. It should be kept in mind that explosives are generally unstable compounds.

decomposition FACTS: WHAT HAPPENS TO A BODY AFTER DEATH (WARNING - Not for the squeamish) UPON DEATH Nature is very efficient at breaking down human corpses. When you die your heart stops pumping blood around your body, thus depriving your cells of oxygen, which rapidly begin to die. Decomposing starts almost immediately, with the skin going through several changes in colour as the blood stops circulating leaving the body an ashen color. However different cells die at different rates. Upon death blood also starts to settle in the those parts of the body that are closest to the ground, turning the top part grayish white and waxy looking, whilst darkening the underside. Funeral directors (Undertakers) tend to lift the head of a corpse in the coffin in order to prevent discolouring of the face. The intestines are packed with millions of micro-organisms that don't die with the person. EMBALMING Embalming is the practice of preserving human (or animal) remains.

The Blood Typing Game - about blood groups, blood typing and blood transfusions What happens if you get a blood transfusion with the wrong blood type? Even though a patient's own blood type is the first choice for blood transfusions, it's not always available at the blood bank. Try to save some patients' lives and learn about human blood types! Play the Blood Typing Game About this game Embed the Blood Typing Game onto your own web site or blog Swedish version of the game 2012 Winner of the Best Game Category by Swedish Learning Awards "The winner has created a minimalistic but, at the same time, captivating graphic design which grabs the user's curiosity. See a Video about the Blood Typing Game 3 min. 1. ploster34802. Listed are players who have the highest number of treated patients within the last 24 hours.