Sunday, 18 August 2013



Genetic engineering, also called genetic modification, is the direct manipulation of an organism's genome using biotechnology. (Indirect genetic modification through artificial selectionhas been practiced for centuries.) New DNA may be inserted in the host genome by first isolating and copying the genetic material of interest using molecular cloning methods to generate a DNA sequence, or by synthesizing the DNA, and then inserting this construct into the host organism.Genes may be removed, or "knocked out", using a nucleaseGene targeting is a different technique that uses homologous recombination to change an endogenous gene, and can be used to delete a gene, remove exons, add a gene, or introduce point mutations.
An organism that is generated through genetic engineering is considered to be a genetically modified organism (GMO). The first GMOs were bacteria in 1973; GM mice were generated in 1974. Insulin-producing bacteria were commercialized in 1982 and genetically modified food has been sold since 1994. Glofish, the first GMO designed as a pet, was first sold in the United States December in 2003.[1]
Genetic engineering techniques have been applied in numerous fields including research, agriculture, industrial biotechnology, and medicine. Enzymes used in laundry detergent and medicines such as insulin and human growth hormone are now manufactured in GM cells, experimental GM cell lines and GM animals such as mice or zebrafish are being used for research purposes, and genetically modified crops have been commercialized.

POTENTIAL USES OF STEM CELL

POTENTIAL USES OF STEM CELL





Thursday, 15 August 2013

History Of Spontaneous Human Combustion (SHC)

Spontaneous Human Combustion (SHC)

Spontaneous Human Combustion (SHC)

The enigma of spontaneous human combustion (SHC) is considered the most bizarre and frightening of all the phenomena in the world of the unexplained and the unknown. Some believe that stories of SHC are only urban legends, eerie tales of people bursting into flames that never really happened to real people. But this is not the case. Urban legends happen to a friend of a friend, but are really untraceable back to any true original narrator of the event. In the case of spontaneous human combustion, one is left with the charred remains and ashes of individuals who were once fully living, breathing, feeling human beings.
Spontaneous human combustion is included in the chapter on ghosts and hauntings because for centuries certain scientists and psychical researchers have suggested that the phenomena may be due to some kind of internalized psychokinetic facet of the human mind. Poltergeists have been known to cause spontaneous outbreaks of fires, and mysterious fires and lights have been part of the repertoire of a haunted house since humans first began to keep records of such phenomena. Then, too, there are those theorists who place the blame for SHC directly on vengeful spirits or malicious entities from other dimensions of reality. Whatever the true cause of SHC, such accounts have haunted men and women for centuries, thus the mystery is placed in this chapter.
In December 2001, a 73-year-old woman in Garden Grove, California, died from the third-degree burns that she had suffered over 90 percent of her body. Firefighters and the coroner's office were left with the puzzle of how this could be possible when the fire took only four minutes to extinguish and was confined to a couch, a table, and the chair in which the victim was sitting.
Was this another case of spontaneous human combustion? In many ways it is similiar to so many other unexplained instances of SHC.
On March 24, 1997, 76-year-old John O'Connor was found dead in his living room at Gortaleen in northernIreland. An intense and localized heat had left only his head, upper torso, and feet unburned, as well as the chair in which he was sitting. There was very little smoke damage done to the room or the furniture.
In December 1956, Virginia Caget of HonoluluHawaii, walked into the room of Young Sik Kim, a 78-year-old disabled person, to find him enveloped in blue flames. By the time firemen arrived on the scene, Kim and his easy chair were ashes. Strangely enough, nearby curtains and clothing were untouched by fire, in spite of the fierce heat that would have been necessary to consume a human being.
On August 19, 1966, Doris Lee Jacobs of Occano, California, burned to death in her trailer home at 1342 23rd Street. Although Jacobs suffered burns on over 95 percent of her body, the inside of the trailer was only partially scorched. Officials could offer no explanation for the fire, because it was the woman, not the trailer, who had burst into flames.
How can human flesh be heir to such dangers as spontaneous combustion? Spontaneous combustion, it is assumed, is confined to oily rags and newspapers piled up in poorly ventilated corners of basements and garages.
On September 20, 1938, in Chelmsford, England, a woman burst into blue flames in the midst of a crowded dance floor. No one was able to extinguish the blaze that seemed to be fed by her own flesh, and in minutes she was but a heap of ashes.
On July 30, 1937, a woman who had been paddling about in a small boat with her husband and children at England's Norfolk Broads was engulfed by terrible blue flames and was nothing but a mound of ash in a matter of a few horrifying moments. Neither any member of her family nor the wooden boat was harmed.
Dr. D. J. Gee, a lecturer in forensic medicine at the University of Leeds, England, wrote of a case of SHC for the journal Medicine, Science and the Law (5:378, January 1965). According to Gee, the victim was a slim, 85-year-old woman who lived with her son and daughter-in-law in a ground-floor apartment. Her family had left the apartment by 9:30 a.m. on the day she died. Neighbors had discovered smoke issuing from a kitchen window and found the smoldering remains of a human body on the hearth.
When Gee visited the apartment two hours later, he noticed that the room was exceedingly warm and the ceiling felt hot. The paintwork was blistered and the walls and furnishings begrimed by soot. Only a part of the wooden edge of the hearth was burned, and a small section, approximately one foot in diameter, of the floor was damaged. The rug had not been burned, but it was greasy with tiny fragments of fat. A tea towel lying near where the body had been found was barely singed, and a large pile of dry firewood remained unaffected.
Gee concluded from his examination that the woman must have suffered a heart attack and fallen into the fire. The body was ignited at the head by the fire and had been sufficiently inflammable to burn to such an extensive degree without any other source of heat, like a candle. The draft from the chimney had prevented the spread of flames to other parts of the room.
In a 1961 study Dr. Gavin Thurston studied the literature of SHC and came to a number of conclusions, among them:
  1. That under certain conditions a body will burn in its own fat with little or no damage to surrounding objects.
  2. The combustion is not spontaneous, but started by an external source of heat.
  3. This has occurred where the body has been in the path of a draft up a chimney from a lighted fire. Oxygenation of the flue prevents outward spread of the fire.
In order to test Thurston's theories, Gee conducted some experiments of his own. He learned that human fat, when melted in a crucible, would only burn at a temperature somewhere near 250 degrees centigrade. However, a cloth wick prepared in liquid fat will burn even when the temperature of the fat has dropped as low as 24 degrees centigrade.
Gee also enveloped a layer of human fat in several layers of thin cloth in order to produce a roll about eight inches long. Combustion of the roll proceeded slowly along its length, burning with a smoky yellow flame and producing a great deal of soot. In both of these experiments, a fan was arranged so that combustion would proceed in a direction opposite the flow of air.
Gee admitted that these experiments were by no means conclusive, but argued that they supported the theory put forward by Thurston, which he believed to be the most reasonable explanation for the occurrence of spontaneous human combustion.
On April 7, 1969, Grace Walker of Long Beach, California, was found on the floor of her living room with burns covering 90 percent of her body. Although she was still alive when discovered, she was pronounced dead on arrival at the hospital. Investigating police officers said that the only signs of fire in the house were the ashes left from Walker's clothes, which had been burned from her body by the flames from her flesh. There were no burners lighted on the stove and not a single match was to be found in Walker's house. Friends and relatives said that the woman did not smoke and never carried matches on her person.
The strange phenomenon of ball lightning has been used by many scientists in an attempt to explain the even stranger mystery of spontaneous human combustion, but it is as difficult to isolate in laboratories for study as SHC. In 1960, Louise Matthews of South Philadelphia survived an eerie experience that might substantiate the theory of ball lightning as a factor in at least some of the mysterious cremations that have taken place throughout the world and throughout all recorded time. Matthews claimed that she was lying on her living room sofa when she glanced up to see a large red ball of fire come through both the closed window and the venetian blinds without harming either. At first Matthews thought that an atomic bomb had fallen, and she buried her face in the sofa. But the ball of fire passed through the living room, into the dining room, and drifted out through a closed dining room window. Matthews said that it made a sizzling noise as it floated through her house. And she was able to exhibit visible proof of her experience: As the ball of fire had passed over her, she had felt a tingling sensation in the back of her head. Her scalp was left as smooth and clean as her face.
In his experiments regarding the effects of fire on flesh and bone, Dr. Wilton Krogman, professor of physical anthropology at the University of Pennsylvania, tested bones still encased in human flesh, bones devoid of flesh but not yet allowed to dry out, and bones that have dried. He burned cadavers in a wide variety of fires fed by such combustibles as hickory and oak, gasoline, oil, coal, and acetylene. Krogman learned that it takes a terrific amount of heat to completely consume a human body, both flesh and skeleton. Cadavers that were burned in a crematorium burn at 2,000 degrees Fahrenheit for more than eight hours, burning under the best possible conditions of both heat and combustion, with everything controlled, are still not reduced to ash or powder. Only at temperatures in excess of 3,000 degrees Fahrenheit did he observe bone fuse so that it ran and became volatile.
How, then, can a human being burn beyond recognitionin a number of cases in less than an houryet not cause the fire to spread beyond the chair in which the victim was sitting or the small area of the floor on which he or she might have sprawled? According to Krogman, the temperatures required to bring about such immolation should ignite and consume anything capable of burning within a considerable radius of the blaze.
In what has become one of the classic cases of SHC, Mary H. Reeser of St. Petersburg, Florida, was last seen relaxing comfortably in an armchair in her apartment at 9:00 p.m. on Sunday evening, July 2, 1951. When a telegram was delivered to her 11 hours later, nothing remained of the 170-pound woman but a skull that had shrunk to the size of a baseball, one vertebra, and a left foot wearing the charred remains of a black slipper.
St. Petersburg Fire Chief Nesbit said that he had never seen anything like it in all his years of investigating fires. Police Chief J. R. Reichart received an FBI report stating that there was no evidence that any kind of inflammable fluids, volatile liquids, chemicals, or other accelerants had been used to set the widow's body ablaze. A spokesman for a St. Petersburg mattress company pointed out that there is not enough material in any overstuffed chair to cremate a human body. Cotton, he said, comprises the basic stuffing of such a chair, and this material is often combined with felt and hair or foam-rubber cushions. None of these materials is capable of bursting suddenly into violent flames, although they do possess properties that enable them to smolder for long periods of time.
At first Krogman theorized that a "super lightning bolt" might have struck Reeser, her body serving as a conductor to ground the current through a wall-type heater behind the chair. He discarded this theory as soon as he learned that local weather bureau records showed no lightning in St. Petersburg on the night Reeser met her bizarre death.
Krogman remarked that he had never seen a skull so shrunken or a body so completely consumed by heat. Such evidence was contrary to normal experience, and he regarded it as the most amazing thing he had ever seen. If he were living in the Middle Ages, he mused, he would suspect black magic.
Spontaneous human combustion seems to strike without warning and without leaving a clue. It seems to occur primarily among the elderly and among women, but there is no standard rule for these grim cases of preternatural combustibility. Nearly every theory, such as that those who imbibe heavily might be more susceptible to the burning death, has been disproved and rejected. At this time, no investigator has determined the critical set of circumstances that might bring body cells to the stage at which they might spontaneously burst into the flames that feed on the body's own fatty tissue, and SHC remains a baffling mystery in the annals of the unexplained and the unknown.

Spontaneous Human Combustion (SHC)

Spontaneous human combustion (SHC) describes reported cases of the burning of a living (or very recently deceased) human body without an apparent external source of ignition. As of 1995, there have been about 200 cited cases[1] worldwide over a period of around 300 years.
There are many hypotheses that attempt to explain human spontaneous combustion. These include several natural explanations as well as supernatural and biblical explanations.
Natural explanations include those:
  • Intestinal conversion of food into methane by methanogens which when released through the pores of the skin can catch fire when triggered by various sources (e.g., silk cloth generating static electricity).[2]
  • Based on unknown or otherwise unobserved phenomena (e.g., that the production of abnormally concentrated gas or raised levels of blood alcohol might cause spontaneous ignition)[citation needed]
  • Relating to health and lifestyle factors (e.g. smoking, not consuming adequate levels of water, etc.)[citation needed]
  • That involve an external source of ignition (e.g., the victim was drunk and dropped a cigarette)[citation needed]
Objections to natural explanations typically refer to the degree of burning of the body with respect to its surroundings. Indeed, one of the common markers of a case of SHC is that the body – or part of it – suffered an extraordinarily large degree of burning while the surroundings or the lower limbs remained comparatively undamaged.[1]
Supernatural[citation needed] and biblical explanations of spontaneous human combustion remain popular. In the latter case, some people[according to whom?] interpret Bible passages (such as Num 11:1[3]) to be indicative of spontaneous human combustion.

Characteristics[edit source | editbeta]

The spontaneous combustion of people (i.e. death from a fire originating within the victim’s body without a direct external cause) is a theoretical explanation for a number of unexplained cases, some of which are well-documented but many of which are not. The more intriguing cases share the following characteristics:
  • The body is completely or almost completely incinerated, while nearby furniture exposed to high temperatures remains intact. Damage is limited to the victim’s body and clothing, to the area of the floor or furniture on which he or she died and to the ceiling above the corpse.
  • The torso is the focus of the fire and if remains are found these are of the extremities, such as the feet.
  • There are no traces of fire accelerant and the fire does not have an evident external cause.
  • Often the combustion seems to happen simultaneously at many parts of the body, usually without any obvious points of origin.
  • The victim is typically alone at the time of death and is thought to have been alive when the fire started, despite showing little sign of having struggled.[4]

Forensic investigation[edit source | editbeta]

An extensive two-year research project—involving thirty historical cases of alleged SHC—was conducted in 1984 by science investigator Joe Nickell and forensic analyst John F. Fischer. Their lengthy, two-part report was published in the journal of theInternational Association of Arson Investigators,[5][6] as well as part of a book.[7] Nickell has written frequently on the subject,[5][6][7]appeared on television documentaries, conducted additional research, and lectured at the New York State Academy of Fire Science at Montour Falls, NY, as a guest instructor.
Nickell and Fischer’s investigation—which looked at cases in the eighteenth, nineteenth, and twentieth centuries—showed that, again and again, the burned bodies were near plausible sources for the ignition: candles, lamps, fireplaces, and so on. Sometimes these sources were left out of popular accounts of the alleged phenomenon while they were hyped as mysterious. The investigations also found that there was a correlation between alleged SHC deaths and victims’ drunkenness or other incapacitation that could have caused them to be careless with fire and less able to respond properly to an accident. Where the destruction of the body was not extensive, the significant fuel source was the victim’s clothing.
However, where the destruction was extensive, additional fuel sources were involved, such as chair stuffing, floor coverings, the flooring itself, and the like. The investigators described how such materials helped retain melted fat to burn and destroy more of the body, yielding still more liquified fat, in a cyclic process known as the “wick effect” (or “candle effect”).
That nearby objects often went undamaged was not a scientific mystery but a matter of physics. Fire tends to burn upward, and it burns laterally with some difficulty. The fires in question are relatively small, achieving considerable destruction by the wick effect, and relatively nearby objects may not be close enough to catch fire themselves (much as one can get rather close to a modest campfire without burning). As with other mysteries, Nickell and Fischer cautioned against a one-explanation-fits-all approach but rather urged investigating on a case-by-case basis.[citation needed]

Suggested explanations[edit source | editbeta]

Many hypotheses attempt to explain how SHC might occur but according to those that rely on scientific understanding, incidents that might appear as spontaneous combustion actually had an external source of ignition – and the likelihood of true spontaneous human combustion is quite low.[8] Benjamin Radford, science writer and deputy editor of the science magazine Skeptical Inquirer, casts doubt on the plausibility of spontaneous human combustion, “If SHC is a real phenomenon (and not the result of an elderly or infirm person being too close to a flame source), why doesn’t it happen more often? There are 6 billion people in the world, and yet we don’t see reports of people bursting into flame while walking down the street, attending football games, or sipping a coffee at a local Starbucks.”[9]Paranormal researcher Brian Dunning states that SHC stories “are simply the rare cases where a natural death in isolation has been followed by a slow combustion from some nearby source of ignition.” Other stories of people suddenly aflame should be called “Unsolved deaths by fire”; just because the cause was not discovered does not mean SHC occurs.[10]

Natural explanations[edit source | editbeta]

  • Almost all cases of SHC involve persons with low mobility, due to advanced age or obesity, along with poor health.[11] Victims show a high likelihood of having died in their sleep, or of being unable to move once they had caught fire.
  • Cigarettes are often seen as the source of fire, as the improper disposal of smoking materials causes one of every four fire deaths in the USA.[12] Natural causes such as heart attacks may lead to the victim dying, subsequently dropping the cigarette, which after a period of smouldering can ignite the victim’s clothes.[13]
  • The “wick effect” hypothesis suggests that a small external flame source, such as a burning cigarette, chars the clothing of the victim at a location, splitting the skin and releasing subcutaneous fat, which is in turn absorbed into the burned clothing, acting as a wick. This combustion can continue for as long as the fuel is available. This hypothesis has been successfully tested with animal tissue (pig) and is consistent with evidence recovered from cases of human combustion.[14][15] The human body typically has enough stored energy in fat and other chemical stores to fully combust the body; even lean people have several pounds of fat in their tissues. This fat, once heated by the burning clothing, wicks into the clothing much as candle wax (which typically was originally made of animal fat) wicks into a lit candle wick to provide the fuel needed to keep the wick burning.[16]
  • Scalding can cause burn-like injuries, including death, without setting fire to clothing. Although not applicable in cases where the body is charred and burnt, this has been suggested as a cause in at least one claimed SHC-like event.[17]
  • Brian J. Ford has suggested that ketosis, possibly caused by alcoholism or low-carb dieting, produces acetone, which is highlyflammable and could therefore lead to apparently spontaneous combustion.[18][19]

Unverified natural phenomena[edit source | editbeta]

  • Another hypothesis suggests high-energy particles or gamma rays[1] coupled with susceptibilities in the potential victim (e.g., increased alcohol in the blood) trigger the initial reaction. This process may use no external oxygen to spread throughout the body, since it may not be an “oxidation-reduction” reaction. However, no reaction mechanism has been proposed.

Notable examples[edit source | editbeta]

Henry Thomas, a 73-year-old man, was found burned to death in the living room of his council house on the Rassau council estate inEbbw Vale, south Wales in 1980. His entire body was incinerated, leaving only his skull and a portion of each leg below the knee. The feet and legs were still clothed in socks and trousers. Half of the chair in which he had been sitting was also destroyed. Police forensic officers decided that the incineration of Thomas was due to the wick effect. His death was ruled 'death by burning', as he had plainly inhaled the contents of his own combustion.[20]
In December 2010, the death of Michael Faherty in County Galway, Ireland was recorded as "spontaneous combustion" by the coroner. Dr Ciaran McLoughlin, made this statement at the inquiry into the death: "This fire was thoroughly investigated and I'm left with the conclusion that this fits into the category of spontaneous human combustion, for which there is no adequate explanation."[21]

In August 2013, Rahul, a two and half months old infant from Tamil NaduIndia, has had four reported burn injuries since he was born. He is being treated at the Kilpauk Medical College and Hospital in Chennai.[2][22] Initial tests results showed normal functioning of his liver and kidneys; no bone damage was detected. Analysis on his blood, urine and sweat have not been completed.[23]