In January, the "science" rumor list was released, and the dose of the new crown vaccine for children should be halved?

Lanzhou Evening News "Fresh meat suddenly beats because there are parasites" "The dose of the new crown vaccine for children needs to be halved"... It is intended to uncover the truth of the rumors on the "science" rumor list in January 2022, and see the authoritative interpretation.

The monthly "science" rumor list is guided by the Beijing Municipal Association for Science and Technology, the Cyberspace Administration of the Beijing Municipal Party Committee, and the Capital Internet Association, and is jointly released by the Beijing Science and Technology Journalists and Editors Association and the Beijing Regional Website Joint Rumor Dispelling Platform, and supported by the Science and Technology Journalists and Editorial Committee of the China Association of Popular Science Writers, the China Evening News Science Editors and Journalists Association, the Shanghai Science and Technology Communication Association, and the Institute of Science and Technology Information of the Beijing Academy of Science and Technology.

1 The volcanic eruption of Tonga will cause a "year without summer"?

Rumor: After the volcanic eruption in Tonga, a large amount of volcanic ash cannot settle for a long time after entering the stratosphere, resulting in a "parasol effect", which will cause a "summerless year" of global temperature decline.

Truth: Volcanoes do cause the Earth to "cool down," mainly because they inject sulfur-containing aerosols into the atmosphere, which, when they enter the stratosphere, reflect more sunlight, creating a cooling effect in the atmosphere.

The Philippine Pinatubo Eruption Index (VEI), which caused a drop in global average temperatures of 0.5 °C, is 6, and its eruption in 1991 released 20,000 kilotons of sulfur dioxide; the eruption of The Tonga volcano is estimated to be 5-6 magnitude VEI, but the release of sulfur dioxide on the first day of the eruption is only 62 kilotons, which will not have a large impact on global temperature and will not cause a "summerless year". At present, the Tonga volcano is still active and its activity needs to be further monitored. If subsequent volcanoes do not erupt on a larger scale, it will not affect global temperatures for the time being.

2 Morning and evening refueling more money?

Rumor: The amount of gasoline refueling is billed according to the volume, and according to the principle of thermal expansion and contraction, the same quality of gasoline is smaller in the morning and night when the temperature is lower, so it is more cost-effective to refuel in the morning and evening.

Truth: The argument that refueling sooner or later saves money doesn't hold. At present, gas stations have built underground oil storage depots, and have a certain degree of protective layer, gasoline is stored at a constant temperature all year round, and will not be affected by external temperature. Even if the technical level in the early years did not reach the current standard, it was impossible to achieve underground constant temperature oil storage, and the density of gasoline under different temperature conditions did not change much, and the price difference was very small.

3 Is there a parasite when fresh meat suddenly beats?

Rumor: In the New Year goods prepared by every household, it is found that the bought meat will beat spontaneously and you must be careful, which is a manifestation of parasites in the meat.

Truth: In fact, the meat that has just been slaughtered will beat, not because there are parasites, but because the meat is very fresh and the slaughter time is very short.

Shortly after slaughter, the central nervous system of fresh meat has died, but the nerve endings around the muscles have not yet completely died, and the energy substance adenosine triphosphate (ATP) in the muscles has not yet been exhausted. Therefore, under the slight stimulation of the outside world, the muscles can also produce beating, which is also called "super-reaction". After a period of slaughter, the ATP in the meat is exhausted, and the muscle fibers lock up and do not beat.

4Prepared dishes are not fresh or contain preservatives?

Rumors: Compared with fresh dishes, the most popular Chinese New Year's Eve rice pre-made dishes in this year's Spring Festival are not fresh after freezing and reheating, and some pre-made dishes have a shelf life of up to one year and definitely contain additives and preservatives.

Truth: Prepared dishes are no different from the foods we usually eat, with no additional preservatives added. The standardized and traceable production and processing process will make the taste of dishes more stable and the quality safer. Factory pre-made dishes are standardized production, consumers take home as long as they are placed on the gas stove to heat up to restore the taste, the degree of taste recovery and dine-in fresh stir-fry is comparable.

Most of the prepared dishes need to be cooked at high temperatures, which is itself a sterilization process; then the use of liquid nitrogen and other quick-freezing techniques, through ultra-low temperature freezing, can completely inhibit the reproduction of microorganisms, so there is no need to add additional preservatives. On the other hand, according to the requirements of the packaging standard, all the raw materials should be listed, so the relevant additives in the seasoning used will appear in the ingredient list.

But that doesn't mean that pre-made dishes add more additives than dine-in or homemade dishes. Even foods that consumers buy and cook themselves often contain additives. As long as it meets the additive standards set by the state, the rational use of additives will not cause harm to the human body.

5The dose of the COVID-19 vaccine for children should be halved?

Myth: Most children's medications are used according to the amount of adult medication halved or reduced. The dose of the COVID-19 vaccine given to children also needs to be halved, otherwise the body will be "overloaded".

Truth: Currently, the dose and composition of the COVID-19 vaccine is exactly the same for all ages, including children. The use of a uniform dose while ensuring safety is a global approach. The dosage of therapeutic drugs is either considered weight, and some also consider the surface area of the body, which is related to factors such as pharmacokinetics of drugs in vivo and liver metabolism.

However, the mechanism of vaccine function is different from that of therapeutic drugs, after the antigen in the vaccine enters the body, it is not directly "exerting the drug effect", but through the immune system to present the antigen, the immune cell recognizes the antibody, and the antibody then plays a role in blocking viral infection or preventing the onset of disease. The above process has no correlation with body surface area and weight.

In fact, the vast majority of vaccine doses do not distinguish between adults and children. For example, there is no dose difference between hepatitis B vaccine, cervical cancer vaccine, and pneumonia vaccine. In terms of mechanism, after the vaccine enters the body of a child, the mechanism of producing antibodies is exactly the same as that of adults, and there is no difference.

6 "Cold fireworks" temperature is low, no danger of firing?

Rumor: As the name suggests, "cold fireworks" are fired at a low temperature and do not belong to dangerous goods such as fireworks and firecrackers.

Truth: The term "cold fireworks" is misleading, they are not only fireworks, but also the basic properties of flammable and explosive dangerous goods have not changed.

"Fairy stick" and "electronic fireworks" are fired, and the temperature decreases rapidly after the flame (spark) is emitted, and the temperature drops to about 80 ° C at 20 cm from the jet port, and the temperature at 50 cm from the jet port drops to about 40 ° C, so it is commonly known as "cold fireworks". When firing such products, the temperature at the injection port is as high as 700-800 ° C, which can still burn the human body and ignite flammable substances.

Therefore, when producing, operating, storing and discharging "cold fireworks", it is still necessary to strictly abide by the regulations on the safety management of fireworks and firecrackers. When the public discharges "cold fireworks", safety measures generally applicable to fireworks and firecracker products should be adopted, and it is strictly forbidden to display fireworks indoors and in any place where fireworks and firecrackers are prohibited.

7 Baby wearing diapers will lead to "O-legs"?

Myth: Diapers will make the baby's legs unable to be together, and when the child grows up, it will become "O-legs"!

Truth: "O-legs" have nothing to do with diapers. The fetus is curled up in the mother's belly, and the legs are O-shaped, which will continue to be about 2 years old after the birth of the fetus, which is a normal phenomenon.

After the age of 2, as babies learn to walk and squat, in order to adapt to physiological needs, their lower limbs will adjust themselves and gradually become "X" shaped appearance, and the degree of "X" is often the most obvious when they are about 4-5 years old. After the age of 6, the curvature of the "X" shape gradually decreases. Growing to about 7-8 years old, the legs gradually develop the same appearance as adults.

The current disposable diaper design has no restrictions on the baby's leg movement, and the legs can be naturally extended and frequently moved to make the joints and muscles develop normally. Therefore, the baby's "O-shaped legs" before the age of 2 are normal developmental conditions and are not caused by diapers. If there is really an abnormal situation, it cannot be ignored, and the baby must be taken to the hospital for diagnosis and treatment by a doctor, and do not correct it yourself.

Lanzhou Daily all-media reporter He Yan