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Find the answer to the question: Can worms hear?

“Do worms have the ability to listen?” is a question of "age" because people have been searching for the answer for hundreds of years.

Many people have concluded that worms cannot hear, but a new study published in the scientific journal Neuron suggests the opposite.

Sound sensor
Complex organs such as sight are common in the animal kingdom, but hearing is found only in vertebrates and some arthropods. Most animals with hearing possess a vibrating organ.

The worm C. elegans can sense sound waves.
The worm C. elegans can sense sound waves.

When sound waves hit the body, the nerve cells that process the sound pick up on this signal. In humans or other vertebrates, it is the ear with a structure consisting of the eardrum and the inner ear.

Meanwhile, C. elegans, the roundworm commonly used in scientific experiments, does not have a specialized auditory organ. Instead, new research shows that its skin acts as a membrane that senses sound.

From there, the entire body of this worm is an eardrum. This is also the first study to provide evidence that an invertebrate, not a member of the arthropod family, can sense sound traveling through the air.

Mr. Shawn Xu, the study's lead author, working at the University of Michigan, USA, said that previously, many studies on C. elegans showed that this 1-mm-long worm can smell, taste and touch. made of leather. This means that this species has senses to perceive and perceive light.

“This species lacks only one thing, that is the sense of hearing. Therefore, our research every year aims to find this sense," explained Mr. Xu.

According to the biologist, the results of the study confirm a major step forward in discovering how organisms perceive sound. By extension, hearing may have evolved in earless organisms such as mollusks or other worms. From there, shedding light on the ability to perceive sound of some "earless" creatures .

Many animals do not have eardrums, so they are technically unable to process sound. However, they may have developed other components to do this.

For example, frogs have inner ears but no eardrums. Their skin and bones work together to guide sound waves to the inner ear. Meanwhile, spiders or some other small insects pick up sound waves thanks to especially sensitive hairs on their legs.

To find out how worms hear or perceive sound, Xu's experiment was to emit loud noises towards them. Previously, scientists had genetically modified the worms' other senses so that they could only sense changes through sound waves. The results showed that, in the absence of senses such as sight and touch, C. elegans worms still crawled toward the opposite direction from the source of the sound.

Elizabeth Ronan, co-author of the study, said that the worms have developed the ability to process sound to hear the noises of enemies such as predators, winged insects and escape.

Frog inner ear but no eardrum.
Frog inner ear but no eardrum.

Feel or listen?
However, just seeing the worms turn away from the sound is not enough evidence that this species actually perceives sound waves . They can only sense the physical movement of sound waves on their skin instead of picking up signals through the nervous system.

Therefore, the scientists continued to change the genetic pattern of this species, causing them to develop blisters on the skin. In theory, these wounds would block the skin's ability to perceive sound.

By experimenting with multiple species of worms and studying genetics, the team of scientists eventually found the nicotinic receptor for acetylcholine , a neurotransmitter located under the surface of C. elegans' skin. These receptors are capable of detecting sound waves and informing the brain.

Overall, the experiments show that C. elegans can sense and respond to airborne sound waves through a mechanism that is both genetically unique and somewhat similar to hearing. But whether they actually hear it is another question.

Some scientists think that listening is an activity that requires a deeper level of perception, such as associating sounds with cognitive abilities. Therefore, Xu's study showed that worms sense and respond to sounds in the air, so they do not meet the criteria for sound perception. Perception requires the object to process the signals and then give the signal a specific meaning.

However, at least sensing sound waves has been able to help the worms stay away from predators and survive to this day. The study also sets the stage for scientists to continue to learn about how the earliest animals appeared on Earth to perceive sounds. Because they exist in the form of mollusks, without ears or eardrums, they need a special way to survive and evolve to this day.

New technique of coronary artery bypass surgery: 5 hours surgery, ten years of good health

Department of Cardiology - University of Medicine and Pharmacy Hospital, Ho Chi Minh City, has just applied a new technique: bridging coronary arteries with 2 thoracic arteries, helping to clear 4-5 blockages at the same time; The lifespan of the bridge is about 10-15 years.

Mr. Do Van D. (55 years old, Go Vap) has been suffering from angina for the past 5 years, and often has to be treated with medication. But a month ago, Mr. had to go to the emergency room because of a heart attack. Through coronary angiography, the doctors discovered that the patient had narrowing of many coronary arteries.

One patient had multiple occlusions in the coronary arteries that could not be completely resolved by over-stent placement. Meanwhile, with traditional coronary bypass surgery using blood vessels in the legs or arms, after 5 years, 70% of these bridges will be re-obstructed.

Therefore, on October 5, doctors from the Department of Cardiology and Cardiology - Ho Chi Minh City University of Medicine and Pharmacy Hospital applied a new technique, coronary artery bypass with 2 thoracic arteries. One day later, the patient was extubated and was able to leave the care room.

Bridge "run well" 10-15 years!

Coronary artery disease is more and more severe, due to increasing favorable factors such as diabetes, high blood pressure, sedentary lifestyle,... Patients with coronary artery disease often have chest pain, chest heaviest, especially when exertion. Coronary artery narrowing due to plaque to a certain extent will cause patients to have erratic angina, possibly even leading to a heart attack.

BS. Nguyen Hoang Dinh - Head of Cardiovascular Surgery Department warned, "Patients with coronary heart disease are getting younger and younger. For cardiologists, patients under 60 are still 'young.'

For treatment, people usually put stents. But 10-15% of patients with coronary artery disease. Patients cannot have stents placed due to narrowing in many places, or because the coronary stenosis is in a rather special position, so when stenting can cause sudden death at that time, therefore, new cardiologists. using coronary bypass surgery."

A heart surgery at the Department of Cardiovascular Surgery - University of Medicine and Pharmacy Hospital. (Photo: Hoang Dinh)

Traditional coronary bypass is to take a healthy blood vessel such as the one in the leg or arm, or the left internal thoracic artery to make a bridge. But the question is, how long will this "bridge" last?

"After 5 years, 70% of the bridge by the saphenous vein in the leg will be blocked. The radial artery in the arm gives better results, but because the muscle is too thick, it can cause spasm. Meanwhile, the internal thoracic artery is good. 98% of the internal thoracic artery bypass is still open after 10-15 years.However

, for patients with too many stenosis, a left internal thoracic artery is not sufficient. With techniques from French cardiac surgeons, we applied multi-vessel coronary bypass with both left and right internal aorta," said Dr. Hoang Dinh said.

The internal aorta is the artery that feeds the chest. However, in this area there is a fairly dense vascular system, so the use of two thoracic arteries at the same time does not have a great effect.

The doctors will completely separate the right internal thoracic artery, and then make a Y-shaped connection with the left internal thoracic artery. Then these two Y-shaped branches surround the heart. The first branch of the left internal thoracic artery will be bridged through the most important occlusion. And the right thoracic artery will in turn connect through the narrowed coronary branches.

In the past 6 months, doctors here have performed 15 coronary surgeries, including patients with obesity and kidney failure. There are currently no cases of complications. This surgery can take about 5-6 hours. The cost for an operation is 65 million VND. For patients with health insurance, the maximum reimbursement is 20 million VND.

The Messenger spacecraft is about to fly by Mercury


The US space agency NASA has announced that the Mercury probe, called Messenger, will make a flyby of the solar system's smallest planet early next week, according to AFP. This is the second Mercury flyby of the Messenger spacecraft.

During the first Mercury flyby on January 14, 2008, the Messenger spacecraft sent back to Earth thousands of images and other research data about this planet closest to the Sun.

According to NASA, next Monday (October 6), the Messenger spacecraft will fly 201 km from Mercury and send back about 1,200 images of the planet's surface.

The 1.2-ton, car-sized Messenger probe, worth about $446 million, was launched into space by NASA on August 3, 2004 in Florida (USA) on a Boeing Delta II rocket. During its six-and-a-half year journey, the train will fly an estimated 7.8 billion kilometers.

Although Mercury is only 91 million km from Earth, but because there is not enough fuel needed to fly into the orbit of the smallest planet in this solar system, Messenger must make many round trips to take advantage of the force. gravity of Earth, Venus, Sun.

To date, the Messenger spacecraft has passed by Earth once in August 2005, passing Venus twice in October 2006 and June 2007. In addition to the first approach to Mercury in January 2008 and the second on October 6, the Messenger spacecraft also flew close to Mercury once on September 29, 2009 before entering the planet's orbit on March 13, 2011 to catch up. to embark on an exploration mission within a year.

It is known that in 1973, NASA's Mariner 10 probe was launched to Mercury. Mariner 10 passed Mercury three times in 1974 and 1975 and recorded 45% of the minor planet's surface.

The Messenger spacecraft is about to fly by Mercury The US space agency NASA has just announced that the Mercury probe called Messenger will have a flyby of the solar system's smallest planet early next week.

https://knowledgeatworld.com/knowledge/underground-stadium-25156

Underground Stadium To create an advantage in the competition to host the 2018 World Cup, Qatar is planning to build an underground stadium in the capital Doha.

The shocking truth written on the epitaph in the Persian royal tomb unearthed in China

The Persian Empire, the forerunner of present-day Iran, has a long history from the period 690-330 BC with its territory throughout West and Central Asia in its heyday.

By the 200s BC, the Persian empire had established a relationship with another ancient civilization, China, cultural exchange became even more prevalent under the Tang Dynasty thanks to the arrival of silk road.

With this period, many Persians lived in the territory of Dai Tang, studying in the capital Chang'an (now Xi'an) of the Tang Dynasty. Even many members of the royal family also moved to settle in Chang'an.

In 1955, an ancient tomb of the Persian royal family was discovered in the city of Xi'an. The tombstone is inscribed in both Old Persian and Chinese languages. The Chinese inscription on the stele shows that the owner of the tomb is the wife of Prince Suren, who died when she was only 26 years old.

Suren was the prince of the New Persian Empire - the last Zoroastrian dynasty of the Persian Empire before the rise of Islam. Prince Suren came to Dai Duong to settle down during the reign of King Duong Thai Tong. Due to the royal family background of the neighboring country, Suren was ordained an official in the Tang dynasty and lived in Tuong An.

However, when the royal Persian tombstone was studied by Western scholars, Old Persian inscriptions showed that the owner of the tomb was not the wife but the daughter of Prince Suren. This makes Chinese experts extremely confused, two languages ​​appear on the tombstone, so which one is correct?

The shocking secret on the royal epitaph
Facing this concern, experts on Zoroastrianism (the oldest religion in Persia) think that this fact can be explained. In ancient times, Zoroastrianism placed a great deal of importance on the pure color line, especially with the Persian royal family. To this end, many members of the royal family of Persia were willing to marry by blood with their own children, brothers and sisters.

For Prince Suren, it seems that he has remarried to his own daughter, so the woman in the tomb is both his wife and daughter.

Prince Suren hid his secret during his time as a mandarin in Dai Duong. (Illustration image: Internet)

A 1996 Darwin College study published in Science Direct also found that inbreeding in Zoroastrianism was encouraged by "supernatural interests" in Persian beliefs. This practice not only appeared in the royal family but also existed outside the royal family, but the consequences caused by it were extremely heavy.

The results of the excavation of the tomb of the Persian prince surprised many Chinese archaeologists. Under the Tang Dynasty, inbreeding was listed in the "Ten Evils" (the 10 most dangerous crimes such as treason, killing many people without reason, impersonating a king).

Although he is a foreigner, Prince Suren has lived and worked as an official in Chang'an, so if he is found guilty of this crime, he will certainly still be severely punished.

Prince Suren of Persia kept a secret all his life, and it only became clear after thousands of years. Lucky for him that the Tang emperor could not understand Persian, otherwise Suren would have suffered a terrible punishment!

The secret of thousands of moss-covered stone statues expressing all emotions

In the famous Otagi Nenbutsu-ji temple in Kyoto, Japan, there are 1200 unique stone statues with completely different expressions.

Otagi Nenbutsu-ji is a temple on the outskirts of Arashiyama, Kyoto, Japan. The temple is famous for its collection of 1200 unique stone statues. Otagi Nenbutsu-ji Temple is nestled in the hills west of Arashiyama and has 1200 statues representing disciples of Buddha.

Otagi Shrine was originally not built in Arashiyama but in the Higashiyama area in 770. However, this shrine was completely washed away when the water of the nearby Kamo-gawa River flooded its banks. During the early years of the Heian period (794-1192), the temple was re-established in the northeast of Kyoto. However, over time it fell into disrepair, until only three structures remained: the main hall, the Jizo Hall and the temple gate.

In 1922, in order to preserve the remnants of the temple, the government decided to dismantle the remaining structures of the temple and reassemble in the present location. Despite the relocation, the temple continued to be damaged when a massive storm caused terrible damage in 1950.

In 1955, the fortunes of the temple began to change when a new abbot was appointed. His name was Kocho Nishimura and when he arrived, he began to rebuild the temple.

Kocho Nishimura is not only a monk but also a talented sculptor. He came up with the idea for visitors to create statues for the temple themselves under his guidance.

These rakan statues represent the disciples of Buddha. Statues were added to the temple between 1981 and 1991, but they look much older now because of the moss covered in them. Because each statue is carved by a different person, the statues are completely different with impressive faces and expressions.

Image of eagles in battle

The moment three bald eagles in the US fight each other in the air over a fish has been captured on camera.


Immediately after catching the fish in the sea, an eagle grabbed the prey and flew up. But two other eagles suddenly appeared and competed for the spoils. A fierce battle in the air broke out in an instant. At one point two of the three eagles gripped the fish with their talons.

Harry Eggens, a 56-year-old Dutch photographer, captured this scene in Alaska, USA. He said the fight lasted only a few seconds.

“ There were about 150 to 300 other eagles flying around at that time. The two eagles grabbed the fish with their talons for a few seconds. Because they stopped flying, they fell down. When falling close to the ground, both of them release their prey to fly up. I was lucky enough to witness this scene, because normally there are only two eagles fighting. Such hand-to-hand combat is rare ,” Eggens told the Telegraph.

According to the Telegraph, the bald eagle is an American symbol. US law prohibits shooting or injuring eagles in the wild. They can weigh up to 6 kg and have a wingspan of up to 2.4 m. The average body length of a bald eagle is 90-100 cm. This bird of prey lives in the US, Canada and northern Mexico.

To catch fish, eagles often fly close to the surface of the water and catch fish with their talons. They easily defeat other birds of prey, but the outcome of the battle between eagles depends on the strength of each one.

Bald eagles can dive from above at a speed of 158 km / h. They can reach speeds of 70 km/h when gliding and 50 km/h when catching fish. This bird has an average lifespan of 20 years in the wild, but they can live up to 50 years in captivity.

Birds also like 'the subject of registration for the opposite'.



Lower caste females will also prefer lower caste males, at least in the avian world.

This is the study by Marie-Jeanne Holveck of the Center for Function and Evolution in Montpellier, France and published in the journal Royal Society . Experimental study on falcon (a species of sparrow).

Fragile birds. Hidden: Max Planck Institute for Ornithology
Biologists previously thought that females would prefer the best males around. But the experiment proved otherwise. Adult females show a preference for the songs of males of the same class.
According to Marie-Jeanne, low and high caste birds differed in every important characteristic, including metabolism, longevity and attractiveness.

First, the researchers produced low- and high-level falcons simply by changing the size of their nests. Marie-Jeanne explains that in larger nests there will be more competition between the chicks which in turn will produce chicks of lesser qualities.

Then, Holveck's group began to experiment with the preference of lower-ranking females for males. The female birds were placed in observable cages, trained to peck at two buttons, and each time they pecked at one, a male's song was heard. One button is the song of the superior male, the other is the song of the inferior male.

"It's an effective test, it tells us what children like to hear," says Professor Holveck. The lower level female continuously pecks at the button with the song of the lower male and vice versa. In falconry, only males can sing and this is an important erotic signal for females.

In the second part of the experiment, Professor Holveck found that the preference for singing leads to an actual external attraction.

“ Couples of the same rank often reproduce faster, giving eggs faster than other couples of the same rank. The main reason we can come up with is that they are more accepting of each other thus moving on faster. What was most surprising was that the females seemed to determine the caste they belonged to. We will study to explain why they do that .”

According to Joseph Tobias, a zoologist at the University of Oxford, this finding is very interesting. "Although it doesn't reverse previous thinking about evolution, it does reveal some interesting things about nature when it comes to mate selection."

" This suggests that the environment in which an individual lives will have a strong influence on an individual's tendency to be sexually attractive in adulthood ."

Komodo dragons are native to Australia


Scientists have found evidence that the world's largest living lizard - the Komodo dragon - likely evolved in Australia and dispersed westward to its present home on the Indonesian islands.

Previously, researchers thought that the Komodo dragon (Varanus komodoensis) descended from a smaller species isolated on islands in Indonesia. In order to compete with other predators, they have gradually grown in size.

Over the past three years, however, an international team of scientists has unearthed many fossils in eastern Australia dating from 300,000 to 4,000,000 years ago and confirmed they belong to the Komodo dragon species.

Komodo Dragon (Photo: Dita Alangkara)

" When we compared these fossils with the bones of modern Komodo dragons, we found them to be identical," said Scott Hocknull, vertebrate paleontologist at the Queensland Museum, Australia. know - Now we can say Australia is the birthplace of the 3m Komodo dragon ".

According to Scott Hocknull's research team, the ancestors of the Komodo dragon most likely developed in Australia and spread westward, reaching the island of Flores in Indonesia about 900,000 years ago. Comparing the fossils and Komodo dragons currently living on the island of Flores, they found that the body size of this lizard has been relatively stable since that time.

One question is why Komodo dragons are extinct in Australia but still survive on a few remote islands in Indonesia. According to Hocknull, the cause may be due to the impact of climate.

Currently, the Komodo dragon is in danger of extinction, with a population of only about 5,000 living on a few islands in eastern Indonesia, between Java and Australia.

Watch a comedy every day to 'chase' the disease away



Watching just half an hour of comedy a day can lower blood levels of stress hormones and heart disease-causing chemicals, a new finding has found.

The findings reinforce the long-held view that laughter is the body's tonic.

Dr. Lee Berk, from Loma Linda University in California, studied 20 men and women who were taking medication for diabetes, high blood pressure and high cholesterol.

All took their usual medication, but half were also prescribed a "happy laugh" prescription - in the form of 30 minutes of comedy a day.

As a result, stress hormone levels in the comedy group decreased after 2 months.

After four months, levels of chemicals linked to hardening of the blood vessels and other heart problems also decreased, while levels of good cholesterol (considered heart protection) increased.

An earlier study by Dr. Berk also showed that smiling can have health benefits.

More easy childbirth morning intelligence?

Pregnant women with a lot of morning sickness may be relieved to know that feeling nauseous in early pregnancy is a sign that the baby will have a high IQ, according to a UK study.

Researchers have found that women who have a lot of morning sickness in the first weeks of pregnancy give birth to babies with more intelligence and better language skills.

4 out of 5 pregnant women experience morning sickness at the beginning of pregnancy. While there is no answer, some scientists hypothesize that morning sickness is caused by an increase in hormones that protect the fetus and placenta (the hormones thyroxine and human chorionic gonadotropin are secreted during pregnancy) morning).

Researchers at Children's Hospital Toronto believe that morning sickness is also linked to brain development in babies. 121 women who became pregnant between 1998 and 2003 were interviewed. Thirty mothers reported no symptoms of morning sickness, while the rest had symptoms such as fatigue, vomiting and nausea. The team then tested the IQs of children born to these mothers when they were between the ages of 3 and 7. Other factors such as the mother's IQ, smoking and drinking history The mother's alcohol consumption and education level were also considered.

“Children of mothers with morning sickness had higher IQs than children whose mothers had no symptoms during pregnancy. These children also had higher scores on language tests and in simple math," the researchers report in the journal Pediatrics.

The biggest flaw in this study is that morning sickness is just a recall of a time that happened a long time ago. In addition, the study also needs to be conducted on a larger group of subjects for the most accurate results.

Lead researcher, Dr Gideon Koren, admitted that the conclusions in this study may seem "a bit strange" but it is clear that hormonal changes in the body that lead to morning sickness in pregnant women are very good.

"Pregnancy hormones can cause discomfort for the mother, but on the other hand, they provide better development conditions for the fetus," says Dr. Koren.

According to statistics, about 50% of pregnant women have nausea and vomiting, only 28% have nausea but no vomiting during pregnancy. There is evidence that ginger and acupuncture can help alleviate these uncomfortable symptoms.

Previous studies have shown that nausea is a sign of a healthy pregnancy and a lower risk of heart problems and a lower risk of miscarriage.

In 2006, a study found that morning sickness is often increased due to the use of alcohol, meat, sugar and fat - which helps pregnant women to stay away from unhealthy foods.

Having a sister is happier than having a brother

Sisters make families more open and willing to share problems, while brothers often cause more suffering, a survey has revealed.

Researchers from the University of Ulster (UK) asked 571 people aged 17 to 25 about their lives and found that those who grew up with sisters were generally happier and more balanced.

The influence of daughters is especially important after family shocks such as marriage breakdown.

In the study, participants filled out psychological questionnaires that assessed a range of issues, such as whether they had an optimistic outlook or had any psychological problems.

Lead researcher Professor Tony Cassidy said: "Sisters seem to encourage people to talk more openly and increase family cohesion. However, brothers seem to have the opposite effect. again".

"We'll probably have to think more carefully about how we deal with all-boys families ," he said.

Geri Burnikell, co-partner from the charity Support Line, which often advises families and young people, said: "This is very exciting and is certainly relevant to our experience. Boys tend to cause trouble, especially in families with multiple sons.I think it's important in these situations to give people some independence to talk outside of the family. ".