At he beginning of 2021， the Chinese government said it will provide free COVID﹣19 vaccines（疫苗）to all Chinese citizens. Sine then， millions of people have gotten the vaccine. Let's make a closer look.
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The vaccine is given by injection （注射）. It's suggested to get two doses. You should wait about two weeks after the first dose to get the second one.
Can people of all ages get vaccinated？
The vaccines have been tested among three different age groups： 3 to 17， 18 to 59， and 60 and above. The 18﹣to﹣59 age group has the most data （数据）﹣﹣the vaccines have been proven to be safe to this group. The other two groups are expected to be included soon.
Is there anyone who shouldn't get vaccinated？
Experts say the vaccines are safe for most people. But people who have serious diseases such as cancer or diabetes （糖尿病），or people who are allergic （过敏的） to any of the vaccine's ingredients， should not get it. People who want to get the vaccine should not get any other vaccines during the same period.
Do I still need to wear a mask in public places after I've been vaccinated？
Yes. It takes a few weeks for the body to build immunity after vaccination. This means it's possible for a person to get infected （传染的） just after vaccination. There's also a small chance that your body won't build immunity. So before the population becomes immune to the virus， it's highly encouraged to keep wearing masks， practicing social distancing （社交隔离） and washing your hands after getting vaccinated.
The term ecology (生态) comes from a Greek word that means "the study of the house". Ecology is the study of how all living things interact (相互影响) with their environments. In a way, Earth is the house of all living things. We all live together on this planet and it is our home. Today, we also understand ecology to mean taking care of Earth so that humans, plants and animals can all thrive(兴盛). However, we can damage the environment. Sometimes the damage cannot be changed back to what it was before.
Ecology is a huge area of study. It covers every part of a living creature's ecosystem that affects(影响) its ability to live. Ecology considers how a living thing reacts to climate and soil conditions. It also studies how much clean water is available (可用的) and the amount of natural resources. By learning about how living things, including humans, affect each other, we can make smart decisions that protect all living things and the resources they need.
There are many things that children can do to help make sure that their world stays healthy. The decisions you are making today can affect the future.
Conservation(节约) is one area of ecology where we can all make a difference. It does not matter how old we are or where we live. Conservation means using Earth's limited resources wisely so that they don't run out. When you are home, take a moment to think about how you use resources. Many people waste resources. Leaking toilets, half-filled dishwashers or clothes washers, and unattended hoses all waste precious water. If you leave lights on and appliances running in rooms where they are not being used, you are wasting energy.
There's another way we can help conserve Earth's resources. We can show our support of businesses that make their products using methods and materials that do not damage Earth. By buying their products, we are telling them that we appreciate (感谢) their efforts to be Earth-friendly.
We need to take the time to learn about how to save resources. More importantly, we must then put into practice what we learn. Children can do their part. They can show their families some ways to save resources. Together, we can all make a difference.
①Nobody likes to be sick. Nowadays many children go to the doctor to get medicine when they are sick. In ancient China, they also had doctors. But instead of treating a person after they were already sick, the Chinese believed that preventing an illness before it started was the key to one's health.
②Traditional Chinese Medicine (TCM) has a long history of more than 5,000 years. It is a summary of the experience of the working people over many centuries of struggle against diseases. TCM considers human body as a whole of QI, XING and SHEN. The ideas of YIN-YANG and WU XING are important for TCM. WU XING refers to five basic things in the nature, that is, metal, wood, water, fire, and earth.
③One important part of TCM is Yin-Yang. The Yin-Yang symbol means balance. Hold your hand out with your palm (手掌) up. This side of your hand is the Yin side. The back of your hand is the Yang side. They are opposites, but need each other to be complete. Yin is connected with night while Yang stands for day. The symbol of Yin-Yang shows how balance is important in life and in the body.
④Another important part of TCM is chi. It is life force energy. In ancient Chinese medicine, it is believed that chi flows through the body. If chi is unbalanced or blocked, a person may become sick.
⑤How does Traditional Chinese Medicine work? How is Yin-Yang and chi balances? One way is through acupuncture (针灸), which is the way to unblock chi with the use of thin needles (针). The needles are put into the skin along points on the body where chi is blocked.
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Would you try food made of rubbish? When world leaders got together at the UN for a meeting on climate(气候) change, they had a special lunch. The food was made from something that most of us would throw away. There was a salad made of vegetable scraps(剩菜叶). The leaders also had hamburgers made of fruit left over from juicing.
The UN said this reminded people about food waste and the bad influence it has on climate change. "Food waste is not often noticed in climate change, and that is shameful when so many people are in hunger. " said a government secretary.
Most people don't even realize how much food they throw away every day. Sometimes they cook too much or they don't use it in time. Every year more than one-third of all food produced worldwide goes to waste, according to the UN. Stop the waste, and the whole world could save $300 billion from wasted food. More importantly, it could also do less harm to the environment.
Think about a bag of cheese(奶酪). Before we buy it at the store, people have to raise the cows, deal with the milk, and drive to the shop to sell the cheese. If you throw the cheese away, you have wasted energy, fuel(燃料) and water, which give out greenhouse gases that add to global warming.
The UN said if we stop throwing good food away, we could cut down up to 17 million tons of CO₂. The good of that would be the same as taking one in every four cars off the road.
Are you worried about the mental health of a child you know？Or are you a kid looking for help？
Having good mental health is the key lo healthy development of every child. Kids need good mental health﹣not only to be able to deal with challenges, but also to feel good about themselves, build healthy relationships with others and enjoy life.
A kid's mental health can be influenced by many things, like school life and life events. While children can experience mental health issues（问题） at any age, they are most at risk between the ages of 12﹣16.
Everyone feels sad, angry or upset sometimes, including children. But if a kid feels like this most of the time, it's a sign that they may need help. Other signs include difficulty coping, getting on with others or staying interested in activities.
Some of the common mental health﹣related issues they experience include：
*relationship problems
*eating issues
*bullying（欺凌）
*feeling sad
*worry
*self﹣harm
About I in 4 children aged 4 to 17 have recently experienced a mental health disorder in Australia. If you think your child has a mental health issue, it's necessary to reach out for professional help.
There are plenty of things that can be done to improve mental health and help prevent mental health issues from developing. For example, getting enough sleep, eating well and doing regular physical activities are as important to children as they are to adults.
Long﹣lasting and safe relationship, such as with the child's family, is considered the most influential factor（因素） in a child's life.
As a parent, there are some simple steps you can take to support your child's mental health. These are things like taking an active interest in your child. Encouraging them to talk about what's happening in their life. If you are concerned, get support from your doctor or other health or mental health professionals.
Green Energy for Today and Tomorrow
Did you know that most of the energy we use comes from the sun? For example, the sun helps plants to grow. Plants that grew millions of years ago turned into coal, oil, and natural gas (天然气). We call these fossil fuels (化石燃料).
However, fossil fuels make pollution. This is bad for the Earth. Fossil fuels are also nonrenewable. Some day they will be gone. So, scientists want people to use green energy. Why is green energy important? First, it is clean. It doesn't hurt the Earth. Next, it is renewable. It won't run out. Green energy gives us almost 25% of the electricity we use today.
What are the main sources (来源) of green energy?
Water Power
Water power uses moving water in rivers and dams (堤坝). Moving water has energy. Water power makes 16.6% of the electricity we use.
Wind Power
Is wind power new? No, it isn't. People used wind power many years ago. Wind power makes 4% of the electricity we use.
Solar Power
Soar power comes from sunlight. The sun shines on solar panels (太阳能板), and electricity is made. Solar power is now as cheap as some fossil fuels. It makes 15% of the electricity we use
Biomass (生物质能)
Biomass is energy that we get from plants around us. For example, deadwood or grass is burned in power stations. This makes electricity. Biomass is green energy because we plant new trees or crops (庄稼) after we use it. Biomass makes 2% of the electricity we use.
New Green Energy
Ocean rise and fall each day. This moving water can make electricity. We call it tide power. There is also heat under the Earth's surface. Scientists can use this heat for energy, which is called heat power. We may find other sources of green energy in the future.
Some day, green energy could make 100% of the electricity we use. That's good news for the Earth!
On June 3, the United States Fish & Wildlife Service（USFWS）announced that it would protect the tricolored bats. The animal would be listed under the Endangered Species Act. This follows a similar announcement, made in March, to protect the endangered northern long-eared bats. The two kinds of bats are in danger, mainly because of an illness called white-nose syndrome（综合症）.
"Bats play such an important role in keeping a healthy ecosystem." USFWS director Martha Williams said. "But white-nose syndrome is destroying bats." she added.
White-nose syndrome is caused by a fungus（真菌）. It is known to influence only bats, showing up on the animal's nose and wings. The fungus grows in places that are cold, dark, and wet, like caves. As it hurts a bat's skin, the animal's behavior starts to change. The bat becomes more active than normal, wasting the energy it needs to live.
Worldwide, there are more than 1, 400 kinds of bats. Most bats are insectivores, which means they eat insects. In a single night, bats can eat insects of "up to half their weight." This is good news for farmers, since bats eat insects that harm crops. According to the USFWS, the animals help U.S. farmers save more than $3 billion a year in insect control.
Nowadays there is no treatment for white-nose syndrome. But scientists are developing ways to help bats. A 2018 study found that a special light can kill the fungus. Researchers are also testing a fungus-fighting thing that can be placed around areas where bats live. And they're working on a vaccine（疫苗）. Local villagers also provide suggestions. One example: set bat boxes. The USFWS says it will announce a decision about how to list the tricolored bats by late 2023. A decision about the northern long-eared bats is expected next month.
About 80% of people do not get enough vitamin (维生素) D every day. But this vitamin is very important for your health.
Vitamin D is really important for our bones (骨骼). When we are young, vitamin D builds up our bones and makes them strong. When we are older, we still need vitamin D to keep our bones strong. Our bodies keep the vitamin D in our bones and teeth. Then we lose vitamin D as we work and exercise during the day. But our bodies can't make vitamin D. So we have to get it from outside of our bodies.
Where can a person get this very important vitamin? Vitamin D is in foods like fish and eggs. Sometimes, vitamin D is added to bread, milk, and orange juice. Food is not the only way our bodies can get vitamin D. The sun also gives us vitamin D. If we want to be healthy, we should spend some time in the sun each day. Too much sun is not good for you, but about 15 minutes a day is usually enough. And we should be sure to eat foods that are rich in vitamin D, too.
Your beloved pet may be hurting your sleep, new research finds.
Though pets can be helpful for health, pet owner was likely to have poorer sleep, according to a study.
The researchers corrected factors that could influence sleep, including race （种族）and income （收入） , as well as age, gender （性别）and BMI, and focused on whether a person had a sleep disorder and whether a person had a cat or a dog.
The findings showed that having a dog was connected with a greater chance of having a sleep disorder and having trouble sleeping, while having a cat was connected with having a higher chance of leg jerks （抽搐）in the night. "The age of the pet has a big influence on whether or not they keep you up at night, " van Egmond said. "If you have many pets, they can egg each other on. "
With dogs, it depends a lot on the kind and the activity level it needs. Making sure a pet gets plenty of physical activities and mental stimulation （朿!| 激）during the day can help animals—and their owners—get better rest.
Unlike dogs, cats are more active at night and it is easier to use up their energy. If you play with your cat before it is ready for bed, you would make it hard for cats to fall asleep. If you feed your cat after playing with it, your cat would feel that it has successfully hunted its food and is rewarded with a nice meal in return. Then it goes to sleep quickly.
The new study shows that pets can influence your sleep, but we have to really think about that pets are much more than a pet in our family.
Have you ever had trouble sleeping in a new place?
Lots of people do. And now researchers from Brown University in Rhode Island think they know why. They found that one half of the brain "remains more awake" than the other half when people are trying to sleep in a new place.
The findings were reported m Current Biology by Brown University. In their report, the researchers said many people say they have a harder time sleeping the first night at a hotel or other places outside their homes. They call it "first-night influence". "In Japan, they say. If you change your bed, you can't sleep." said Yuka Sasaki, one of the reporters.
The researchers measured (测量) brain waves for 35 volunteers over two nights in a laboratory. The two nights were a week apart (间隔). They found during the first night the left half of the brain was more active than the right half. This was during the first deep-sleep period, the researchers said.
Sasaki said a lot of questions still remain. Researchers did not keep measuring brain waves all night long. So they don't know if the left half keeps "watch" all night, or whether it "works in shifts (轮换) with the right half later in the night". They also do not know why brain activity, at least during the first period of deep sleep, is always on the left half.
For some, this research may be culming It is good to know that our brain is "looking out for us" in a new place. But it may not help with sleep. That brain activity, at least according to this new research, makes it harder to get the sleep people wake up feeling well-rested in the morning.
