"Sleeping on bare boards can treat lumbar spondylosis" "ID cards will be demagnetized by mobile phones" "Water boiled in electric kettles can damage nerves and cause cancer"... In the past year of 2023, have you considered these so-called "scientific statements" circulating on the Internet? Still convinced?
Not long ago, the "Stop Rumors and Seek True Knowledge - 2023 'Scientific' Rumors Seeking Truth List" sponsored by the Beijing Association for Science and Technology and the Cyberspace Administration of Beijing Municipal Committee was officially announced. Reporters from China Youth Daily and China Youth Daily interviewed many experts, please They sort out and interpret the "scientific" rumors that have been widely circulated in the past year to help the public distinguish right from wrong.
There are many traps in folk “secret recipes”
Have you heard the elders in your family say that sleeping on a bare board bed is good for your waist since you were a child, and have you formed this understanding? On the day the 2023 "Scientific" Rumor Truth List was announced, an interview video was played. From it, it can be seen that 9 out of 10 interviewees held this view. The interviewees said that these were told to them by the older generation. "Common sense", and there are indeed old people who persist in the habit of sleeping on "bare beds" all year round.
"It is very wrong to say that sleeping on a light board bed can treat lumbar spondylosis." said Zhao Bin, chief physician of the emergency department of Beijing Jishuitan Hospital. He told reporters that many people have a misunderstanding that "hard bed" refers to a hard bed or a bare bed. In fact, a hard bed is compared to the soft mattresses that Europeans and Americans are used to. A hard bed does not refer to a hard bed, nor is it a bare bed. Some mattresses must be laid on the hard board.
In order to break this rumor, Zhao Bin started a live demonstration with the cooperation of the staff. "We can see that the normal physiological structure of the human spine has four physiological curvatures, namely cervical curvature, thoracic curvature, lumbar curvature and sacral curvature." Following Zhao Bin's guidance, the reporter saw the cervical spine of the staff lying on the hard bed. , the lower part of the lumbar spine is suspended. Zhao Bin said that such a posture relies too much on shoulder and hip support, which not only fails to relieve low back pain, but also causes spinal distortion.
"A mattress that is too hard will cause the above problems; a mattress that is too soft will not provide proper spinal support. Therefore, you should choose a mattress with moderate hardness. The mattress cannot be so hard that it does not deform, nor does it deform too much." Zhao Bin said.
How to choose the right mattress? He told reporters that we should remember the "3:1 principle": a 3 cm thick mattress will sink 1 cm when pressed, and a 10 cm thick mattress will sink 3 cm. This ratio is moderate between soft and hard.
In his view, relieving low back pain is not a simple matter. Daily maintenance and rehabilitation exercises, avoiding overuse of the lumbar spine, and actively responding to problems when problems arise are all important links in relieving low back pain. "Don't imagine that changing a bed or mattress will completely solve the problem." Zhao Bin said.
In 2023, there was also a saying on the Internet: Since the electric kettle is made of stainless steel and contains manganese, the manganese element will precipitate during the process of boiling water. Long-term intake can damage nerves and even cause cancer.
Test results from the Beijing Physical and Chemical Analysis and Testing Center show that there is no precipitation of manganese when the electric kettle boils water.
Why are rumors contrary to experimental conclusions? Zhang Mei, a researcher at the Institute of Analysis and Testing of the Beijing Academy of Science and Technology (Beijing Physical and Chemical Analysis and Testing Center), told reporters that although the material for the electric kettle liner contains manganese, it exists in the form of a dense tissue. Long-term use of stainless steel kettles can cause The possibility of manganese poisoning is extremely small.
What is the right way to choose a hot water kettle? She said that no matter which type of hot water kettle you buy, you need to check whether the product labels are complete.
"For example, when buying a stainless steel kettle, you should choose food-grade stainless steel such as 304 stainless steel, 316 stainless steel, or an electric kettle with the words 'Executive Standard GB9684-2011' or 'For Food Contact'. If you buy a glass kettle, you should choose High borosilicate glass has stable performance, safe material, and does not easily generate scale. When purchasing a ceramic electric kettle, it is recommended to choose a style with no color or pattern on the inner wall of the kettle to avoid the risk of poisoning caused by the precipitation of toxic elements such as heavy metals. "Zhang Mei said.
“Science” rumors are always around us
Many people believe that the higher the pixels of the camera, the clearer the photos taken. This has become a kind of "common sense", but it is often some "common sense" in life, and it is easier for errors to occur during the dissemination process and form rumors.
"For example, the pixels of a SLR camera may not be as high as those of a mobile phone, but it does not affect the picture taken by a SLR camera more clearly than that of a mobile phone." Chen Zheng, associate professor at the School of Physical Science and Engineering at Beijing Jiaotong University, told reporters that the camera imaging effect is determined by the lens and body Commonly decided, the relationship between camera pixels and photo sharpness is not absolutely relevant.
On the day the Rumor Truth List was announced, Chen Zheng conducted an experiment on the spot. He prepared two CMOS models of different sizes. "This is the main component of the camera - CMOS. Our images will be illuminated on such things through the lens." Chen Zheng introduced that if each pixel is compared to a person, standing on it respectively. In the case of the same 12 million pixels, standing on the small CMOS model looks crowded, but standing on the large CMOS model is more relaxed and comfortable. "The 'fastness' between pixels determines whether the photo is clear or not." Chen Zheng said.
He gave an example of shooting the moon: If you want to take a clearer picture of the moon, you first need a telephoto lens. The longer the focal length of the lens, the better its ability to resolve details. Coupled with a high-pixel, large-size CMOS detector to improve the resolution of the camera, you can take a very clear photo of the moon. In this process, the so-called "high pixels" are only one of the factors that determine the clarity of the photo.
There is a magnetic strip in the ID card. Will it be demagnetized if it is attached to the mobile phone? This is a "scientific" rumor that has been widely spread in 2023. Many people keep their ID cards and mobile phones separately in order to prevent their ID cards from being "degaussed".
According to Zhang Bo, a distinguished associate researcher at the School of Integrated Circuits of Beijing University of Posts and Telecommunications, this is a complete rumor. "The second-generation ID cards that are currently widely used use radio frequency identification technology. There is no magnetic strip inside at all, so there is no chance of being 'degaussed' by the mobile phone." Zhang Bo said.
At the scene, he performed a demonstration: shining a strong flashlight on the inside of the ID card, you can see a small shadow and a surrounding coil. Zhang Bo told reporters that the small shadow is the chip in the ID card and the core part of the ID card. It is responsible for storing and transmitting personal information such as name, address, photo, and fingerprint.
"When we 'swipe the ID card', the coil in the ID card obtains energy through electromagnetic induction, briefly supplies itself with power, and completes an information exchange. The reader reads the information, decodes it, and transmits it to the data processing system, completing an identity process. Verification." Zhang Bo said.
According to him, the ID card uses 13.56MHz radio frequency identification technology. The communication frequency of mobile phones ranges from several hundred to several thousand MHz. The current 5G and future 6G operating frequencies will be higher. “With different operating frequencies, there will be differences between them. It is unlikely to have an impact."
Zhang Bo explained that degaussing of ID cards is usually caused by damage to the chip or coil. He reminded that when using ID cards, avoid twisting, heavy pressure, or placing them at high temperatures to prevent damage to the chip and coil.
"Many times, an experiment can shatter rumors and lead you out of misunderstandings. Most of the experimental equipment we use today are items within easy reach. In fact, science is not aloof, it is reflected in every aspect of our lives. "Zhang Bo said.
China Youth Daily·China Youth Daily trainee reporter Li Ruixuan reporter Qiu Chenhui Source: China Youth Daily