How can you get carsick sitting in the car reading text messages and newspapers?

Sitting in the car reading, the car bumps all the way (whether you notice it or not), and your eyes are always staring at the book, so you will feel dizzy. No matter what medicine you take, you can't stop this phenomenon, so don't read books and newspapers in the car in the future.

Why do you get carsick when reading in the car?

Hain, a professor of otorhinolaryngology at Northwestern University School of Medicine, and Oman, director of the Laboratory for People and Vehicles at the Space Research Center of Massachusetts Institute of Technology, answered:

Motion sickness, whether traveling by car, boat or in outer space, is caused by the inconsistency between the brain's expectation of the external situation and the information received by the senses, resulting in uncomfortable consequences. In order to maintain balance, the brain will combine many data sources, including vision, touch and inner ear balance, especially the inner ear is particularly important for the detection of angular displacement and linear displacement. Most of the time, all sensory inputs are consistent with each other; If these sensory inputs are not in line with the brain's expectation of this situation, it will cause motion sickness, resulting in symptoms such as loss of space, nausea or vomiting.

Suppose you are sitting in the back seat of a car; Your eyes are fixed on the book, you look into the car out of the corner of your eye, and now you tell your brain that you are resting. However, when the car changes gears or turns, the sensory receptors in the inner ear contradict the above information; That's why car sickness often happens in this situation, so it's helpful to look out of the window (the driver doesn't get carsick often, because the information he receives is not contradictory, and the driver also controls the car, so he can know the change of speed in advance. )

Similarly, you can stay on the deck and look at the horizon to avoid seasickness. Once your balance system learns how to deal with the sway of the ship, as the English proverb says, you will not get seasick so easily. Of course, once ashore, your body will still expect the boat to sway for hours or even days, making you feel uncomfortable again. Space flight can also cause motion sickness, and about 70% novice astronauts suffer from this disease. Under the condition of "no gravity" or microgravity, the inner ear cannot detect the "downward" signal. Some astronauts said that no matter which direction they turn, they always feel confused. (translated by Pan Zhenze)

Tate in Willard, Missouri, USA asked:

How long do stars usually live?

Graham, an astronomer in the Department of Geomagnetism at Carnegie College in Washington, DC, USA, provided the following answers:

The life span of a star ranges from millions to billions of years, depending on the speed at which the star runs out of nuclear energy. The light of almost all stars is produced by hydrogen fusion into helium; This process is carried out in the hot and dense core of the star, and its temperature can reach 20 million℃. The rate at which a star generates energy depends on two factors: temperature and gravitational compression on its surface. A star with a large mass consumes fuel faster and emits brighter light than a star with a small mass. Some big stars will run out of all hydrogen in millions of years. On the contrary, we know that some stars with very small mass are extremely economical and can burn continuously for more than the current age of the universe, that is, nearly 654.38+05 billion years.

Our sun has existed for nearly 5 billion years, and there is enough fuel to last for another 5 billion years. Almost all the stars visible in the sky at night are heavier and brighter than our sun (most long-lived stars are darker than the sun, so they can't be seen without a telescope. When the age of the star is coming and the available hydrogen is about to run out, the planet will expand and become brighter; Stars visible to the naked eye are usually at this stage, and their average age is around several hundred million years. On the contrary, Supergiant star's life span is much shorter, like Betelgeuse in Orion, 65438+ 1 100 million years old; Stars use energy and are expected to disintegrate after 6.5438+0 million years, and then may explode to form supernovae. (translated by Pan Zhenze)

Li Yuwen of Taipei asked:

How to identify consanguinity through genes?

Zeng Li Hui, the attending physician of the Department of Gene Medicine of National Taiwan University Hospital, replied:

The appearance and characteristics of human beings are mostly similar to those of their parents, and the substance that determines the genetic characteristics of this blood relative is called DNA, which is what we often call genetic material. DNA exists in all biological cells, half from father and half from mother. We use the analysis technology of genetic medicine to compare the similarity of two people's genetic maps, which can be used as an important basis for blood relationship or identity identification.

There are hundreds of "short repeat sequences" (STRs) scattered in the human genome. These STRs consist of 2-4 nucleotide repeats, and the number of repeats varies from person to person. The scientists carried out polymerase chain reaction on the gene sequence of STR, and then the products were analyzed by capillary electrophoresis. STR repeats more, and electrophoresis runs slowly; STR repeats less and electrophoresis runs faster. According to the running speed and position of PCR products, the number of STR repeats can be accurately calculated. Scientists have found that it is extremely unlikely that any two people will repeat STR exactly the same number of times, so that their DNA can be clearly identified.

This "DNA fingerprint" can be used not only for personal identification, but also for determining blood relationship. Because the STR pattern of offspring is half the same as that of father and half the same as that of mother, it can not only be traced back to parents, but also identify direct blood relatives such as grandparents and grandchildren, and even identify collateral blood relatives such as brothers and sisters and uncles. This article was reprinted from August 2003.

Three methods to prevent carsickness

1. carsick people take Shangshi Zhitong Ointment 1 tablet one hour before taking the bus and stick it on the liver and navel (called Shenque point). If you ride for more than one day, change to another post the next day. Can effectively prevent carsickness.

2. Fasten your seat belt before getting on the bus to prevent internal organs from swimming excessively in the body, which helps to prevent carsickness.

3. There is a piece of ginger in your mouth. People who love carsickness should take a piece of fresh ginger with them and eat 2 pieces of fresh ginger before getting on the bus, which can greatly reduce carsickness.