Written by / Easy White
Today is 12 years after the Wenchuan earthquake,
12 years, 24 years or even hundreds of years later,
We will all remember -
At that moment,
14:28 on May 12, 2008.
At the search and rescue site of the Wenchuan earthquake, in addition to the figure of rescuers, we can also see the figure of search and rescue dogs. Today we take this opportunity to take a look at the "special forces" of earthquake rescue!
Why animals can smell people
Search and rescue dogs use their noses to smell people. The smell of the human body is produced in the process of human metabolism, and it is related to the substances metabolized by people. How much chemical content are there in these substances? After using modern science and technology to detect human odor, the results show that there are hundreds of substances contained in body odor.
Many mammals have only about 1,000 olfactory sensors on the inner wall of their noses, but they can distinguish thousands of different odors, which has puzzled scientists. Recent experiments with rodents have found that mammals use multiple taste sensors to combine to detect a certain odor. Each different combination perceives a different odor. Because of the variety of combinations, animals can distinguish a large number of different odors. The degenerated human sense of smell has become far inferior to that of most mammals. Therefore, we can't personally smell it in the earthquake relief, but can only turn to those animals with a keen sense of smell.
From search and rescue dogs to electronic noses
Dogs are known for their sensitivity to noses, a million times more able to distinguish odors than humans, 18 times hearing, not only a wide field of view, but also the ability to see things in low light conditions. Dogs not only have a good nose, but also docile and obedient to facilitate training, dogs are generally considered to be the best "experts" in search and rescue.
Dogs can search very sharply for those buried in the ruins of the earthquake, but the search and rescue dog must not work more than 30 minutes per work time, otherwise it will be exhausted and its sensitivity will decrease. Since there is always some error in animal recognition of odors, researchers are developing electronic noses that replace animal noses.
Rats can get close to the buried person
Dogs can only smell outside the rubble of the earthquake to find the rescued, while rats can smell people and get close to the buried with their small bodies. When trained mice smell the scent of the buried person, the nerve center sends signals, and there are 3 areas that are most excited, namely the olfactory cortex of the brain that processes the odor signal, the motor neurocortex, and the pleasure center that produces pleasure when receiving certain stimuli. Therefore, the researchers implanted electrodes in these 3 regions of the rat's brain to collect the relevant signals. Each electrode is only 75 microns in diameter and consists of 32 alloy wires.
Whenever the rat successfully finds the odor of the target, it is stimulated with an electric current. After long-term training, the rat will have a conditioned reflex to the smell of the person, and when the smell is smelled again later, the electric shock is no longer needed, and its pleasure center becomes active. At the same time, the electrodes continuously recorded the bioelectric current generated by the neural activity of the mice. Rescuers were able to tell whether the rats had found survivors based on changes in brain currents. But rats have a harder time training obedient animals like dogs. In addition, the current technology can not accurately analyze the changes in the brain current of mice in various unexpected situations, and the probability of misjudgment is still large. Researchers are trying to figure out how to solve these puzzles so that rats can fight earthquakes and provide disaster relief sooner rather than later.
Super Hornet has a search and rescue function
In people's minds, wasps have always seemed to be synonymous with horror and horror. However, scientists have recently discovered that wasps' special sense of smell is sensitive to human odor, so they can be trained to "search and rescue wasps". The cost of training wasp search and rescue is low, and it only takes a short time to complete the training of a wasp. It is common practice to place a "search and rescue wasp" in a cup-shaped device in advance, and once they smell the human body, they will appear urgent and uneasy, and then accelerate their movements and sound an alarm. In return, once they have made a contribution, they receive food rewards from the trainers.
This type of "super wasp" with search and rescue functions is not a terrible insect commonly found in the wild, but a parasitic wasp scientifically called the "red-footed side grooved bee", a rare insect native to the southern United States that does not sting people. What's even more amazing is that in addition to their incredible olfactory search ability, they also have an amazing ability to distinguish between various differences. Researchers claim that in the future, wasps are likely to replace search and rescue dogs that humans have relied on for a long time.
<h1>Today is the 12th anniversary of the Wenchuan earthquake and nurses' day. </h1>
<h1>This day is destined to be sentimental about the loss of life</h1>
<h1>It is also destined to be grateful to those who guard life. </h1>
<h1>Engraving time in grace and pain, but also starting again in injury and courage. </h1>
<h1>Please don't forget who gave us the courage to start again. </h1>