Two years ago, aerospace manufacturer SpaceX shocked the world by landing its reusable booster (助推器) engine-the biggest and most costly part of the rocket used to power spacecraft into low orbit-on an autonomous drone ship in the Atlantic Ocean. Now, California-based startup Rocket Lab, has come up with an even more courageous idea: using parachutes and helicopters to capture the returning booster, or first stage as it is often called, in the air!
Rocket Lab's decision to avoid the propulsive or vertical (垂直的) landing used by SpaceX comes from its business model to keep its Electron rockets small and cost-effective. Standing just 57 feet tall, they are designed to deliver smaller payloads (有效载重) of about 500 pounds for only $5 million a launch. In contrast, the Spaced Falcon 9 rocket measuring 229 feet tall can lift up to 50,000 pounds, costs about $62而Ilion a mission. "We're not in the business of building medium-sized launch vehicles but small ones for customers to get on orbit frequently," said Rocket Lab CEO Peter Beck.
Similar to other rockets, the Electron divides into two once it reaches outer space. While the top part, carrying the load, continues on to its final destination, the booster engine falls back to Earth. The company intends to fix a ballute-a parachute-like braking device-to quickly slow down the booster's supersonic speed (超声速) upon its return into the atmosphere. Once it slows down to a reasonable pace, a helicopter will grab the rocket from midair and put it onto an awaiting ship to transport to the company's headquarters. Beck said: "The grand goal here is that if we can capture the vehicle in wonderful condition, in theory, we should be able to put it back on the pad, charge the batteries up, and go again."
The idea, still in the concept stage, will become one step closer to becoming a reality during Electron's next launch, scheduled for sometime in 3 years. "Engineers will carefully monitor the first stage as it returns, testing its ability to guide its landing with-he best way to slow down its speed," said Beck.
China is one of the first countries to breed a medical culture. In comparison with Western methods, traditional Chinese medicine (TCM) adopts a vastly different approach. For thousands of years, Chinese people have accumulated rich experience in fighting all sorts of diseases, therefore forming a unique medical theory under the guidance of ancient Chinese philosophies.
The core behind TCM is that the human body's life is the consequence of the balance between Yin and Yang. Yang functions to safeguard us against outer harm, and Yin is the inner base to store and provide energy. When the balance between the two aspects is disturbed, people fall ill.
One of the traditional techniques of TCM, acupuncture (针刺疗法) means insertion of needles into superficial structures of the body - usually at acupoints (穴位) - to restore the Yin-Yang balance. It is often accompanied by moxibustion (艾灸疗法), which involves burning mugwort on or near the skin at an acupoint.
The first known text that clearly talks about something like acupuncture and moxibustion as it is practiced today is The Yellow Emperor's Inner Canon. It is the earliest and most important written work of TCM and is considered the fundamental and most representative medical text in China.
Acupuncture and moxibustion have aroused the interest of international medical science circles. And TCM is gradually gaining worldwide recognition. The WHO issued a document in 2002 that appealed to more than 180 countries to adopt TCM as an alternative in their medical policies. In 2010, acupuncture and moxibustion of traditional Chinese medicine were added to the Representative List of the Intangible Cultural Heritage of Humanity by the UNESCO. Presently, TCM has been back in the news for its effectiveness in improving the cure rate of the COVID-19 since its outbreak in January 2020.
I'd been retired for four years, when a friend suggested university. I thought he was joking—I was rubbish at school and failed my 11-plus. But we love to compete over Mastermind and University challenge, and he thought I'd make it. And he was absolutely right!
I did a foundation course first, which was part time at the University Lifelong Learning Centre (LLC), two nights a week and the odd Saturday. I did quite well, and that gave me the confidence to do a full time, three year degree. I'm passionate about art and I always wanted to be here for the journey and not the destination. That sounds really corny, but it was the truth in my case.
Initially it was a bit strange fitting in with my course mates. They were all 18, straight out of sixth form or college. Over time, though, they've all been fine — now, we all get on really well and there is no issue. I've made plenty of friends as a member of the mature students society, and I do some volunteering through the LLC, chatting to prospective students about my experience of coming to university. I tell them my story and basically encourage them to give it a go because you've got nothing to lose. I like to think I've convinced a few of them.
I have no regrets at all. Enrolling in university was the best piece of advice I've received in years, especially post-retirement. I needed routine in my life; I needed purpose. I'm not going to spend my day in the bookies or the pub. If you've got a passion for something, you should pursue it.
Marathon fever is sweeping this country. In recent years, China's ever-growing passion for marathons has been triggered by its economic development and health-conscious middle class. A large number of marathon runners are white-collar workers, civil servants and business people that are keen on leading a healthy lifestyle. Government support, social participation and strong marketing by the sports industry have gradually led to the rapid development of the marathon industry, which is currently valued at 70 billion yuan ($10.77 billion). Due to its large participation and nationwide media report, marathons are considered by local governments an important part of marketing their cities. Thus, many cities list unique routes across local scenic spots and historical attractions, not only to boost people's fitness, but also to promote local tourism.
For many runners, marathons are a way of life." As we get older, the places and opportunities to meet new people decrease. I find that participating in marathons is a simple way to make friends," said Wu, who made many friends in the Xstop Running Community, a running club with 48,000 members established by Xtep, one of the leading distributors of sports merchandise in China.
"The sense of belonging and the mutual encouragement that exists within the running community are very attractive to many people. We easily befriend one another, since we have the same goal: to keep running and never stop," Wu said. Besides, a marathon can be a great way to explore new places. For a runner who also loves traveling, marathons are a solid choice. "Competing in an international marathon is a chance to experience a city or a country you've never visited before," said Meng, an experienced runner from north China's Tianjin Municipality, who often runs in London, New York and Melbourne.
There's a unique perspective that people get running through the streets of a city, distinct ancient buildings or amazing natural settings, he explained, things that somehow just can't be seen by rushing in a car. In addition, during a race, streets are often closed off so you don't have to battle traffic.
My daughters are lovely and attractive. The 4-year-old has big blue eyes and always wears a smile. The 7-year-old's long strawberry blond hair and sweet smile are already turning the boys' heads. I love everything about these girls, and they know it.
But I try not to tell them they're beautiful. My young daughters are totally innocent when it comes to the pressures of being a woman in our society. They know nothing about plastic surgery, diets, "feeling fat" models or eating disorders. We adults know all too much about such things and in the face of this distorted reality we tend to start telling our girls, as soon and often as possible, how beautiful they are.
I know this is wonderfully well-intentioned, and that we want to raise our girls' confidence from the very start. Here's the thing, though. We might think we're building our daughters up by telling them that they are beautiful to us no matter what, but what we're also doing is bringing the beauty pressure home to our littlest girls. The more I talk about beauty and looks, even in a positive way, the more I' m conveying the importance of those things.
However, it doesn't mean I don't praise my girls. Instead of saying "You look beautiful!" I might say the more specific "Don't you look fancy today!" or "Those colors go so well together." It means that I treat my daughters not as my little dolls, but as real people who are developing their own sense of self and style. It means that they are in charge of how they look.
Naturally, I buy most of my girls' clothes. But I don't usually manage their outfit choices. My daughters can go girly with necklaces, or they can choose to give up dresses altogether. Of course we've seen some mismatching, but they own those styles. They never ask if they look pretty, and they walk with an easy confidence that has nothing to do with what I or anyone else will say about how they look. And that's the spirit I want them to take into their teens and adulthood.
Facial expressions carry meaning that is determined by situations and relationships. For example, in American culture the smile is in general an expression of pleasure. Yet it also has other uses. A woman's smile at a police officer does not carry the same meaning as the smile she gives to a young child. A smile may show love or politeness. It can also hide true feelings. It often causes confusion across cultures. For example, many people in Russia consider smiling at strangers in public to be unusual and even improper. Yet many Americans smile freely at strangers in public places (although this is less common in big cities). Some Russians believe that Americans smile in the wrong places; some Americans believe that Russians don't smile enough. In Southeast Asian cultures, a smile is frequently used to cover painful feelings. Vietnamese people may tell a sad story but end the story with a smile.
Our faces show emotions, but we should not attempt to "read" people from another culture as we would "read" someone from our own culture. The fact that members of one culture do not express their emotions as openly as members of another culture, but it does not mean that they do not experience emotions. Rather, there are cultural differences in the amount of facial expressiveness permitted. For example, in public and in formal situations many Japanese do not show their emotions as freely as Americans do. When with friends, Japanese and Americans seem to show their emotions similarly.
It is difficult to conclude about Americans and facial expressiveness because of personal and cultural differences in the United States. People from certain cultural backgrounds in the United States seem to be more facially expressive than others. The key is to try not to judge people whose ways of showing emotion are different. If we judge according to our own cultural habits, we may make the mistake of "reading" the other person incorrectly.
"Every child has a great curiosity about something they love," said Carolyn King, a doctor in Grand Rapids, Michigan. King, who once studied at Wayne State University School of Medicine in Detroit, is the co-founder of a yearly event called Reach Out to Youth (ROTY).
Wayne State has held the event since 1989, which lets kids ages 7 to 11 experience science and medicine in a fun way.
"We're here to help identify future scientists and future physicians," said Richard Baker, director of Medical Education at Wayne State.
Diamond Moore, a medical student and the leading organizer of ROTY, planned a special but interesting day for attendees. Exhibits included a room where you could see a brain, heart, and some other parts of our body, and a room where you could test your reflexes (反射动作). Wayne State teachers and medical students, including Moore, shared their knowledge of medical science with kids.
"This program wants kids to learn about science, arts, and the health care system," Moore said, "so that hopefully, they'll become interested in medicine."
Some of the students were excited about the chance to tour the exhibits and learn more about medicine-related jobs. "A doctor would be a cool job," said first-time attendee Desiree Anders, 9.
Jeremiah Tower, an 11-year-old from Detroit, said that learning about "science and things about the body" was what the program was all about. Still, he wasn't excited about having to get up early on a Saturday morning.
This year's theme (主题) was "Play It Safe: Brain Safety." After seeing what a brain looks like up close, young attendees learned about the danger of concussions (脑震荡). A fun test was given about brain safety so that kids could see how much they had learned.
About 350 kids take part in the program each year. It's a great way to get an idea of what it feels like to be a doctor.
Football T-shirts are more commonly connected with boys than girls. This can often cause a problem when you want to find a cool shirt for a girl. That is not to say that there are no cool shirts out there for girls to wear. The problem is that they are often harder to find than the ones for boys.
You can get custom (订制的) shirt printed for girls from a number of custom print stores. Of course you have to make sure that they are legally allowed to use the logos (商标) and colours of the team you want to support.
You can also go through official channels to get the shirt you want. The official channels will generally be the large sportswear stores or the official stores of the teams. These stores will be able to use the colours of the teams and even put the name of the person who the shirt is for on it.
If you do not feel like you have to try the T-shirts on, then an online store may be your best choice. The reason for this is that you can visit various stores and find the best ones.
If you want to see what the T-shirt looks like in real life, then going to a store is the best choice. Large sportswear stores often have football shirts. These are the best places to go if you do not live close to an official store. And these stores usually have lower prices than the official stores.
As a result of pollution, Lake Erie, on the borders of the USA and Canada, is now without any living things.
Pollution in water is not simply a matter of "poisons" killing large numbers of fish overnight. Very often the effects of pollution are not noticed for many months or years because the first organisms (生物体) to be affected are either plants or plankton(浮游生物). But these organisms are the food of fish and birds and other creatures. When this food disappears, the fish and birds die too. In this way a whole food chain can be wiped out, and it's not until dead fish and water birds are seen at the river's edge or on the seashore that people realize what is happening.
Where do the substances which pollute the water come from? There are two main sources of sewage (污水) and industrial waste. As more detergent (洗涤剂) is used in the home, so more of it is finally put into our rivers, lakes and seas. Detergents harm water bird, dissolving the natural substances which keep their feathers waterproof. Sewage itself, if not properly treated, makes the water dirty and prevents all forms of life in rivers and the sea from receiving the oxygen they need. Industrial waste is even more harmful as there are many highly poisonous things in it, such as copper and lead (铅).
So, if we want to stop this pollution，the answer is simple: sewage and industrial waste must be made clear before flowing into the water. It may already be too late to save some rivers and lakes, but others can still be saved if the correct action is taken at once.
A glimpse at Spring Festival Chinese film releases
The clock is ticking down to 2021! We've handpicked some films to help you get in the spirit of the season.
Hi, Mom
The film is widely regarded as the top dark horse thanks to its tear-jerking narration of mother-daughter affection, which is directed by Jia Ling.
Time： Feb. 12—14 9：30 a. m.~11:30 a.m.
Place： Room 1
Treats： Popcorn, Ice cream
Price： ¥80
Detective Chinatown 3
Directed by Chen Sicheng, this movie topped the list of the most-anticipated holiday films sent by movie ticketing platform Maoyan.
Time： Feb. 14-16 1：00p. m.〜3：00P.m.
Place: Room 2
Treats： Popcorn, Ice cream （for free）
Price： ¥75
A Writer Odyssey
Director Lu Yang showed a boldly imaginative visualization of a horrible fantasy world, taking the third seat with 410 million yuan.
Time： Feb. 13—17 9:30 a. m. 11:30 a. m.
Place： Room 3
Price： ¥ 65
Endgame
The film illustrates a comical up and down fate between an unsuccessful theater actor and a famous professional assassin（刺客）who loses his memory accidentally.
Time： Feb. 15 — 18 3：30 p. m.〜5：30 p. m.
Place： Room 4
Price： ¥60
Welcome to book through the WeChat account!
Will life in the future be better, worse or the same as now? Futurologists (未来学家) predict that life will probably be very different in 2050.
First of all, it seems that TV channels will have disappeared by 2050. A computer will send the program directly to the television. On TV screen appear holograms (全息图) , which are pictures with certain height, width and depth. We will be able to see, smell and touch the things that we see on television.
Water has become one of our most serious problems. Agriculture is changing and people are growing more fruit and vegetables to export. Demand for water will increase ten times in 2050. Some futurologists predict that water will be the cause of war if we don't act now.
In transport, cars will run on new fuels and go very fast. A car will have computers to control its speed and there won't be any accidents. On the other hand, space planes will take people around the earth in about three hours. People will fly from Los Angeles to 'Tokyo by space plane in just half an hour.
In the field of technology, robots will have replaced people in factories. By 2050, we will see robots everywhere. They do not ask for pay rises or go on strike, and they work 24 hours a day.
Medicine technology will have conquered many diseases by 2050; we will be able to help blind and deaf people see again and hear again. Scientists have discovered how to control genes. They have already produced clones of animals and will be able to produce clones of people and decide how they look, how they behave and how much intelligence they have. lf you want all this to come true, you should study science and technology hard.
During my first year of college, I went on a trip with a group of classmates to New York City for fun. At the end of the day, several of the students suggested hanging out in the city for a while before getting dinner. They ended up spending thousands of dollars at the clothing store. It was only when they had finished that they decided to eat dinner at a place across the street. In the nicest restaurant I had ever been to, I ordered the cheapest appetizer I could find, and sat in silence as the students around me reminisced about their most recent vacations to Europe.
When the dinner was over, a student suggested seeing a Broadway play, and one guy told the group Cabaret was playing for only $ 250 a ticket. I knew I wasn't going to be spending $ 250 for a show. "I have a lot of homework," I said. "But thanks anyway." I walked back to the hotel alone.
To be very honest, I find it fascinating to be surrounded by classmates who come from wealthy families I have never experienced. Meanwhile, I'm not embarrassed for being unable to afford the things my classmates buy. I'm proud of who I am, and where I've come from.
On the other hand, one of my classmates had gotten to college on a needs-based scholarship. He didn't have any money. He didn't have a car and relied on brisk walks to get anywhere. He couldn't even afford food, so he worked part time at college food service to make a few dollars and grab leftovers for meals. He certainly kept me grounded as I felt like a spoiled brat using money so freely and buying myself a sandwich whenever I felt hungry.
So, while I was ridiculously wondering about my insufficiency, he showed what real determination and pride were.
Staying positive through the cold season could be your best defense against getting sick, a new American study suggests.
In an experiment that exposed healthy volunteers to a cold or flu virus, researchers found that people with a generally sunny character were less likely to fail ill.
The findings, published in the journal Psychosomatic Medicine, build on evidence that a "positive emotional style" can help ward off the common cold and other illness.
"People with a positive emotional style may have different immune (免疫的) responses to the virus," explained lead study author Dr Sheldon Cohen of Carnegie Mellon University in Pittsburgh. "And when they do get a cold, they may interpret their illness as being less severe."
Cohen and his colleagues has found in a previous study that happier people seemed less likely to catch a cold, but some questions remained as to whether the emotional quality itself had the effect.
For the new study, the researchers had 193 healthy adults complete standard measures of personality qualities, physicals health and "emotional style".
Those who tended to be happy, energetic and easy–going were judged as having a positive emotional style, while those who were often unhappy, tense and hostile（敌意的）had a negative style.
Afterwards, the researchers gave them nose drops containing either a cold virus or a particular flu virus that causes flu-like symptoms. Over the next six days, the volunteers reported on any aches, pains, sneezing they had. Cohen and his colleagues found that happy people were less likely to develop a cold.
What`s more, when happy folks did develop a cold, their symptoms were less severe than expected based on objective measures.
In contrast, people with negative characters were not at increased risk of developing a cold based on objective measures, though they did tend to get down about their symptoms.
"We find that it`s really positive emotions that have the big effect," Cohen said, "not the negative ones."
So can a bad-tempered person fight a cold by deciding to be happy?
If you have failed in the past to try to make big changes in life, try again now, one tiny step at a time.
Every year it's the same. As December comes to an end, you think about the new year and all the ways you want to improve your life. But as you start to write down your hopes for the new year, you think about the last year. You excitedly write down all the changes you are going to make, but by the end of January those ideas get lost in your busy life.
Here's a suggestion: Forget the too big, hard-to-achieve goals and just think about the small ones. "We often think that we have to do everything in big steps. Even though it's so hard for us to reach it. " said Robert Maurer, who recently wrote the book One Small Step Can Change Your Life. "What we try to do is to begin with such a small step that we can't find any excuse not to do it. "
"Kaizen", a Japanese word, is used to mean to change behavior and attitudes(态度). During World War Ⅱ, American factory managers were able to increase productivity by trying small continuous improvements instead of sudden changes. After the war, the idea was brought to a rebuilding(重建) Japan. It made Japan develop fast. The Japanese called it "Kaizen", which means" improvement".
Maurer studied the idea and did some experiments with it: "Kaizen" could possibly help people succeed in doing everything.
Have you ever been sad because of failure? Please re member, for quite often achieving what you set out to do is not the most important thing.
A boy decided to dig a deep hole behind his house. As he was working, a couple of older boys stopped by to watch. "What are you doing?" asked one of the visitors. "I want to dig a hole all the way through the earth!" the boy answered excitedly. The older boys began to laugh, telling him that digging a hole all the way through the earth was impossible. After a while, the boy picked up a jar. He showed it to the visitors. It was full of all kinds of stones and insects. Then he said calmly and confidently, "Maybe I can't finish digging all the way through the earth, but look at what I've found during this period!"
The boy's goal was far too difficult, but it did cause him to go on. And that is what a goal is for-to cause us to move in the direction we have chosen, in other words, to cause us to keep working!
Not every goal will be fully achieved. Not every job will end up with a success. Not every dream will come true. But when you fall short of your aim, maybe you can say, "Yes, but look at what I've found along the way! There are so many wonderful things having come into my life because I tried to do something!" It is in the digging that life is lived. Itis the unexpected joy on the journey that really makes sense.
"Inspector Sands to the control room, please." If you ever hear that at a British train station, don't panic. But you might appreciate knowing that this is a codeword meant to inform staff that there is an emergency somewhere in the building. The idea is to avoid causing alarm among commuters (通勤者), but still get the message out to those trained to deal with the problem.
The subject of secret codewords like this was raised this week on Reddit, and the discussion has attracted thousands of examples. But what codewords and signs are really out there in the wild?
A good place to start is hospital emergency codes. These are often colour-coded, and one health centre in Canada has published its list online. "Code red" announces a fire, "code white" indicates a violent person while "code black" means a bomb threat is active. It's been reported that hospital staff sometimes refer to the morgue as "Rose Cottage", in order to avoid upsetting relatives of a patient who has recently died.
"I can see very good reasons for having these codes," says Paul Baker, a linguist at the University of Lancaster. "It may be that people are unsure when they're giving the code so there's no point upsetting members of the public."
Not all codes are alphanumeric (字母数字的). Some are visual, intended to be hidden in plain sight. As BBC Future discovered earlier this year, many banknotes feature a specific pattern of dots placed there to prevent people from photocopying money. Many copiers and scanners are programmed to spot it.
And finally, the spray-painted squiggles (波形曲线) you see on pavements in towns and cities all over the world are codes understood by construction workers and engineers. For example, in UK, different colours are related to different types of cable or pipe. Blue meant a water system while yellow indicated gas lines and green labelled CCTV or data wiring.
All of these codes have a purpose — to avoid causing panic, to transmit subtle signals in social groups, or to provide technical information quickly and easily. "People don't like secrets, do they?" says Baker. "There is a drive to have as much information as possible — we do live in the information age," he adds.
Few fruits carry more health-promoting antioxidants （抗氧化剂） than blackcurrants （黑 加仑 ） . Widely grown in cooler parts of Europe, they are in high demand from consumers seeking chemical-free juices made from the berries. Farmers, though, can struggle to increase productions without relying on chemicals. That could change, not just for blackcurrants but other fruit too, with the careful use of probiotics（益生菌） .
Probiotics is mostly known for its use of tiny 1iving things, including certain bacteria, to restore or improve the digestion in people and animals. But plants can benefit from bacteria too. Among: other things, bacteria help plants produce things that keep: disease-causing viruses off their leaves, support them in collecting nutrition from the environment and help them melt minerals found in the soil.
Knowing all this. Virgilija Gaveliene and Sigita Jurkoniene. of the Institute of Botany Nature Research Centre in Lithuania, set out to find a way to use probiotics to increase the production of blackcurrant bushes, which are grown in that country. The researchers also knew from other work that the production of strawberries and raspberries could be increased by exposing: plants to a carefully selected mix of bacteria.
As they report in Agriculural Science and Technology the results were impressive. While thousand blackcurrants collected randomly weighed just over 538 grams,; the same number from the field exposed-to bacteria treatments weighed nearly 783 grams. A similar increase was also true for the field using the probiotics.
Drs. Jurkoniene and Gaveliene are convinced that: the right mix of bacteria can help blackcurrant farmers meet demand without using chemicals. And it could help other growers. What works for berries should in theory work for other fruit like apples, pears and oranges. More experiments are needed to be sure.
Imagine that you could rewind the clock 20 years, and you're 20 years younger. How do you feel? Well, if you're at all like the subjects in an experiment by Harvard psychologist Ellen Langer, you actually feel as if your body clock has been turned back two decades. Langer did a study like this with a group of elderly men some years ago, redecorating an old New England hotel so that every visible sign said it was 20 years earlier. The men — in their late 70s and early 80s — were told not to just think about the past, but to actually act as if they had traveled back in time. The idea was to see if changing the men's mindset about their own age might lead to actual changes in health and fitness.
Langer's findings were shocking: After just one week, the men in the experimental group (compared with controls of the same age) had more joint flexibility and less arthritis in their hands. Their mental sensitivity had risen measurably, and they had improved posture. Outsiders who were shown the men's photographs judged them to be significantly younger than the controls. In other words, the aging process had to some extent gone in the opposite direction.
Though this sounds a bit woo-wooey, Langer and her Harvard colleagues have been running similarly inventive experiments for decades, and the accumulated weight of the evidence is convincing. Her theory, argued in her new book, Counterclockwise, is that we are all victims of our own stereotypes about aging and health. We mindlessly accept negative cultural cues about disease and old age, and these cues shape our self-concepts and our behavior. If we can shake loose from the negative stereotypes that strongly influence our thinking about health, we can "mindfully" open ourselves to possibilities for more productive lives even into old age.
Silk Road Tours
Along this over 4, 000 km road, you can experience colorful culture, precious historical relics and beautiful northern and western landscape!
Top Silk Road Attractions:
1. Terracotta Warriors□
Type: History Museums, Historic Sites
Recommended Length of Visit： 3 hours
As the eighth wonder of the ancient world, it has a history of more than 2, 200 years. Oriental mummies await you to discover their mystery.
2. Mogao Grottoes□
Type: Buddhism, Historic Sites
Recommended Length of Visit：3 hours
Considered as the eastern Louvre Museum, Mpga0 Grottoes is a glorious treasure of ancient Buddhist cave art. The history of Mogao Grottoes can be traced back to the "Five Hu—16Kingdoms" period (AD 304 — 439).
3. Big Wild Goose Pagoda□
Type: Culture & History, Buddhism
Recommended Length of Visit: 2 hours
For hundreds of years, this great pagoda has always been the symbol of Xi an. It is famous for the great traveler Xuanzang of Tang Dynasty who traveled from China to India to learn the Buddhism and got back to China with many precious Buddhist scriptures (佛经).
4. Qinghai Lake
Type: Lake
Recommended Length of Visit: 5 hours
Known as the largest inland lake, as well as the largest salt water lake in China, it is the most visited and famous attraction in Qinghai Province. Here, you not only enjoy the fantastic natural beauty, but also experience the amazing culture here.
◎Please click " "to add the attraction to your favorite list. Let us plan a private Silk Road Tour for you!
The worsening air quality in tropical (热带的) cities is causing ever greater threats to people's health and this trend will only get worse as the urbanization (城市化) is progressing quickly, scientists have warned. In a newly published study, a team of researchers explain that across all the 46 cities they surveyed from Africa to Asia, they have measured significant annual increases in pollutants harmful to health.
This trend is troubling as tropical cities usually lack proper air pollution monitoring measures and policies to deal with the problem. "These cities are predicted to reach populations of up to 80 million people by 2100, so actions targeting human-related pollution are badly needed," the scientists stress.
Already the number of people dying prematurely (过早地) from long exposure to air pollution has been on the increase and people living in cities in South Asia are the worst affected. In Dhaka, Bangladesh, some 24,000 people die of such causes each year while around 100,000 people die in Indian cities such as Mumbai, Bangalore etc.
"The number of deaths in tropical cities in Africa is still lower due to recent improvements in health care there. But the worst effects of air pollution on health will likely occur in the coming decades," the scientists say.
The reasons for worsening air quality in tropical cities lie in increasing road traffic, waste burning, and the widespread use of coal and wood. Industry is also partly to blame. "Open burning for land clearance in the past contributed most to air pollution in the tropics," explains Karn Vohra, an author of the study. "Our analysis suggests we're entering a new age when some cities experience rates of air pollution in a year that others experience in a decade," Vohra warns.
