Scientists have successfully recovered RNA, a form of genetic material, from the remains of the Tasmanian tiger, an extinct Australian animal. The discovery could help scientists learn more about these creatures before they disappeared from Earth.
The researchers extracted the recovered RNA from the skin and muscle of a Tasmanian tiger specimen (标本) stored in a Swedish museum since 1891. This is the first time RNA has been successfully recovered from an extinct animal. The Tasmanian tiger was once a top predator, known for hunting kangaroos and other animals. The last known Tasmanian tiger is believed to have died in a Tasmanian zoo in 1936. Emilio Mármol Sánchez, from the Centre for Palaeogenetics, led the study describing these research results. Sánchez believes that the recovered RNA material provides a glimpse into the true biology of the Tasmanian tiger, offering insights into the cells and tissues of these extinct creatures.
While Scientists have in recent years taken RNA from different ancient animals and plants, how long RNA could survive at room temperature has been a subject of debate among researchers. The well-preserved condition of the Tasmanian tiger remains, which were in a state of semi-mummification (半木乃伊化), suggests that RNA can survive for longer periods under certain conditions.
The Tasmanian tiger looked similar to a wolf, except for the tiger-like lines appearing on its back. When people arrived in Australia about 50,000 years ago, large animal population losses followed. The arrival of European colonizers in the 18th century destroyed the remaining populations around the island of Tasmania.
Private “de-extinction” programs have been launched with the aim of bringing back some extinct animals. These include the Tasmanian tiger, flightless dodo bird and wooly mammoth.
However, many researchers have warned about the difficulties of using genetic processes to actually recreate an extinct species. While Sánchez said he too has concerns about such processes, he noted that he does “advocate for more research on the biology of these extinct animals.”
1. What can be gained about Tasmanian tigers from the recovered RNA material?A.The genetic makeup. | B.The social behavior. |
C.The preferred habitats. | D.The migration patterns. |
A.Its close relationship to DNA. |
B.Its recovery from an extinct animal. |
C.Its survival time at room temperature. |
D.Its life process under certain conditions. |
A.He considers it impossible to recreate extinct species. |
B.He opposes them and sees difficulties in the research. |
C.He thinks they are promising but need more research. |
D.He takes genetic preservation measures more seriously. |
A.The Challenges of Biological Research of Extinct Animals |
B.The Potential Benefits from Tasmanian Tiger Remains |
C.The Biological Secrets of the Extinct Tasmanian Tiger |
D.The Recovery of RNA from Tasmanian Tiger Remains |
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【推荐1】The Scientific Reason Why Your Dog Is Helping You Live Longer
Are you one of the 44 percent of Americans with a dog? You have a lot of things to thank your dog for, including getting a great night’s sleep. But as it turns out, man’s best friend isn’t just a great life companion; he (or she) can also help you live longer, according to new research.
A study published in the journal Scientific Reports gathered data on 3.4 million subjects aged 40 to 80, comparing them to Swedish registers of dog owners over an 11-year period. Overall, owners of dogs (especially hunting breeds) have a lower risk of death from cardiovascular(心血管) disease or other causes, the researchers found.
That even goes for people who live alone, which a previous study has found could shorten your life. Single dog owners were 33 percent less likely to die and 11 percent less likely to have a heart attack during the study period, compared to single non-owners.
According to the researchers, the benefits can go both ways: While dog ownership can encourage people to be more physically active, active people may also be more likely to own dogs. Owning a dog might also increase peoples’ social interaction and overall well-being, leading to a longer life. What’s more, a family dog could change the owner’s bacterial microbiome(细菌微生物群) by exposing them to foreign bacteria, which boosts their immune systems against disease. Find out more secrets your pet won’t tell you.
“Dog ownership has many benefits, and we may now be able to count better heart health as one of them,” Dr. Mike Knapton of the British Heart Foundation told the BBC. “However, as many dog owners may agree, the main reason for owning a dog is the sheer joy.”
1. What will probably allow people to enjoy a longer life?A.Living alone without a dog. |
B.Owning a dog. |
C.Following the dog’s living ways. |
D.Being single. |
A.influence | B.break |
C.weaken | D.strengthen |
A.Healthier immune system. |
B.Longer life of the dogs and their owners. |
C.More social interaction and well-being. |
D.Lower risk of heart diseases. |
A.change their life style |
B.better their heart condition |
C.bring them a lot of fun |
D.help them to live longer |
【推荐2】The endangered pandas in the Qinling Mountains might face a new threat: the loss of their food—bamboo, which makes up 99% of their meals.
Adult pandas spend most part of the day eating bamboo and have to take in at least 40 pounds a day to stay healthy. However, a new study published in Nature Climate Change warned that they may soon find their food gone because most of the bamboo in the Qinling Mountains might disappear by the end of the century as a result of the rising temperature worldwide.
A team made up of researchers from Michigan State University and the Chinese Academy of Sciences has studied the effects of climate change on the bamboo in the Qinling Mountains. They have found that bamboo is very sensitive to climate change. “80% to 100% of the bamboo would be gone if the average temperature increases 3.5 degrees worldwide by the end of the century,” said Liu Jianguo, one of the report’s authors.
He added, “This is how much the temperature would rise by 2100 even if all countries will keep their promises in The Paris Agreement. But you know what is happening around the world.”
In recent years, China has been trying its best to protect the endangered pandas by setting up more and bigger nature reserves.
“But it is far from being enough and the endangered pandas need cooperation from the rest of the world, because their future is not just in the hands of the Chinese,” said Shirley Martin from the World Wildlife Fund but not a member of the team.
There are about 260 pandas in the Qinling Mountains. That is about 13% of the China’s wild panda population. In addition, about 375 are living in research centers and zoos in China.
1. What can we learn from the first paragraph?A.The Qinling Mountains can provide enough bamboo for the pandas. |
B.Pandas in the Qinling Mountains are only threatened by the loss of food. |
C.Lots of the bamboo in the Qinling Mountains will probably disappear. |
D.Pandas have already eaten 99% of the bamboo in the Qinling Mountains. |
A.China needs more help from the World Wildlife Fund. |
B.It is difficult to control the temperature rise within 3.5℃. |
C.Bamboo is sensitive to changes in temperature. |
D.China is making great efforts to protect the pandas. |
A.About 260. | B.About 635. |
C.About 2, 635. | D.About 2, 000. |
A.The Disappearance of Bamboo |
B.Necessity to Change Pandas’ Food |
C.A New Threat Faced by the Pandas |
D.Efforts Made to Save Pandas |
【推荐3】In the 16th century, it was not unusual to see armed men standing guard outside Britain’s dovecotes (鸽舍). They were not there to protect the pigeons living inside, but rather to prevent thieves from breaking in and stealing something far more valuable—the birds’ waste.
Chemists in mid-1500s Nuremburg had discovered that the birds’ waste was a rich source of saltpetre, a vital ingredient in the making of gunpowder. As a consequence, for several decades pigeon droppings were almost as valuable as silver. Moreover, waste gathered from the dovecotes was a rich fertiliser, particularly sought after by those with vineyards and orchards (果园).
The dovecote was not only a source of food and revenue in medieval times, but also a status symbol. The privilege of building or owning dovecotes was reserved for the upper class. The right was granted by the king. Those who were allowed to build a dovecote usually placed it in some conspicuous places, so that passersby could behold it.
However, the abundance of dovecotes across the British countryside was not universally welcomed. Even a small dovecote had nesting holes for 500 birds. Each day they flew off to stuff themselves on other people’s crops. By the middle of the 17th century, the disaster of pigeons was so great that poet John Milton voiced his fears that the dangerous doves would turn England into a desert.
Later, vast quantities of natural saltpetre were discovered in Chile and California, destroying the value of pigeon waste as a chemical resource. Keeping pigeons was no longer necessary nor profitable, nor even fashionable. During the 18th and 19th centuries, around 95 per cent of Britain’s dovecotes fell into disuse and were demolished.
Now homeless, the tens of thousands pigeons that had once lived in the dovecotes flew off to find somewhere else to live. A species that in the wild had nested on cliffs, the birds discovered that Britain’s rapidly growing towns and cities were full of the sort of rock-faces they liked to root into—humans called them “buildings”. And so these once noble and attractive birds settled there. Over time they’d become the wild urban pigeons that we know today.
1. Which of the following is NOT pigeon’s function in the past?A.Provide material for gunpowder. | B.Improve the level of soil fertility. |
C.Increase income by selling meat. | D.Promote a man’s social position. |
A.Face-saving. | B.Hand-reaching. | C.Eye-catching. | D.Breath-taking. |
A.To emphasize the danger of land desertification. |
B.To describe the destructive power of the pigeons. |
C.To highlight the local’s deep hatred for pigeons. |
D.To represent pigeon’s strong ability to reproduce. |
A.Pigeons: from Prosper to Problem | B.The Origin of Wild Urban Pigeon |
C.Pros and Cons of Raising Pigeons | D.The Glorious History of Pigeon |
【推荐1】Art and technology have much more in common than one might think. Each of these pursuits is, after all, an attempt by humans to describe and understand the world. Though the methods used to reach that “aha” moment may be different, both art and technology are fundamentally humans, and both play very important roles in the human experience as well as human innovation(革新).
Technology is changing art and opening the doors to new virtual museums and new creative mediums. It is no secret that technology is an increasingly pervasive part of our lives, and its influence is finding its way to the art world. Some of the changes may seem obvious, like the increasing popularity of digital art galleries. But there are other, less expected changes that have made art more accessible to both creators and buyers.
Here is a question for you, “If a computer creates’art’, should it still be considered art?”This puzzlement has laid at the heart of some of the most debatable types of art, AI-produced art. AI-produced art has sold for thousands, but does that mean it is any good? An AI-produced portrait of Edmond de Belamy by French art collective Obvious Art sold for an eye-watering $432,000 in 2018, the most expensive AI painting by far.
The process of creating AI-produced art is not as complex as you may think. Though there are many different paths to creating AI art, in general, artists write algorithms(算法)that are able to “learn” a specific aesthetic(美感)by analyzing thousands of images.
The algorithm then tries to produce new images along the lines of the aesthetics it has learned. You could teach an AI algorithm to “paint” like your favorite artists. This combination of technology and art may someday prove to be one of the most exciting new areas in the art world. And with new AI artists appearing each year, some day may be getting closer.
1. What does the first paragraph mainly talk about?A.Different functions of art and technology. | B.Similar goal of art and technology. |
C.Definition of art and technology. | D.Limit of art and technology. |
A.Widespread. | B.Important. | C.Special. | D.Local. |
A.To stress there is argument on art’s influence. | B.To argue that people have wrong attitudes to art. |
C.To say art can be measured by money. | D.To prove technology’s influence on art. |
A.Aggressive. | B.Neutral. | C.Positive. | D.Critical. |
【推荐2】From writing Shakespeare-style poetry to making music, ChatGPT has amazed the world since its launch in late 2022 by the US-based company OpenAI. It even passed several law exams in four courses at the University of Minnesota, US, according to CNN.
The AI program can answer questions on a whole host of topics and write essays, stories and any other written texts you can think of. It does this by drawing on information collected from a large corpus (语料库) of text data.
What makes ChatGPT so impressive? As Sam Altman, the CEO of OpenAl said in an interview with Forbes, “it's not actually fundamentally new technology that made this (ChatGPT) have a moment.”
According to MIT Technology Review, ChatGPT is based on GPT-3, a large language model. Because texts are more complicated than the meaning of every word combined, language models require a type of neural network(神经网络) that can make sense of texts.
One breakthrough behind today's model is a network called Transformer, which was invented by Google researchers in 2017. The neural network can infer word meanings by tracking where the word appears in a sentence. Transformer can therefore capture the meaning of texts more accurately.
The GPT models built by OpenAI combined Transformer with unsupervised (无人指导的) learning, meaning that the models can learn by themselves without being told what to look at. ChatGPT can now generate human-like responses instantly due to the large scale of texts it learned from.
“One of the biggest problems with ChatGPT is that it comes back, very confidently, with falsities,” Michael Wooldridge at the Alan Turing Institute in London, UK, told The Guardian. This means that ChatGPT doesn’t know the truth about the world — it learns information from various resources but it cannot decide what is true or false.
Some argue that ChatGPT will be used to generate fake news, spread falsities, or be used for ill purposes. As for education, many US schools recently banned students from using ChatGPT on school networks because students began to use it as a shortcut for essays.
1. How does ChatGPT work?A.By making complicated texts simpler. |
B.By gathering a wide variety of information. |
C.By passing several law exams in four courses. |
D.By employing its large collection of information. |
A.A completely new technology. |
B.The ability to track the location of a word. |
C.The combination of a network and self-learning. |
D.Better understanding of the meaning of every word. |
A.False information. | B.Something new. |
C.Various resources. | D.Timely responses. |
A.Because a ban on it has recently been passed. |
B.Because it provides fake news that will mislead students. |
C.Because students use it for the purpose of improving their essays. |
D.Because with it, students finish their assignments without thinking. |
【推荐3】Paying with your palm
Your palm(手掌)could soon be your ticket to a concert, thanks to Amazon One. On Sept 14, Amazon, a tech giant from the United States, announced that it is bringing Amazon One, a palm recognition technology, to music places as a replacement for physical tickets and apps. People just need to wave their hands over a piece of equipment outside the place to connect their palm to a ticketing account. Then they can use their palm to get into other shows and events at the place.
Catching CO2 from air
Carbon dioxide(CO2)is the main kind of greenhouse gas. It is usually the result of human activities, like driving cars and flying airplanes. Now, Swiss company Climeworks has created a machine called Orca to help catch CO2. From its base in Iceland, Orca catches CO2 from the air and keeps it 1, 000 meters underground. Orca can catch 4, 000 tons of CO2 each year-around the same amount of CO2 emissions that 870 cars give off per year.
Creating starch in a lab
Starch(淀粉)is the most important part of human food. Scientists at the Tianjin Institute of Industrial Biotechnology of the Chinese Academy of Sciences have created starch using CO2, hydrogen(氢)and electricity, according to a study published in the journal Science on Sept 24. Lab tests show that synthetic(合成的)starch is about 8.5 times more efficient than starch produced by traditional agriculture. “There are many industries that can benefit from this technology.” Ma Yanhe, the author of the study, told China Daily.
1. What do you know about Amazon One?A.It can be a replacement for music places. |
B.It can help people attend a concert without payment. |
C.It can connect the palm with the recognition system. |
D.It is a piece of palm-sized equipment. |
A.Better quality. | B.Higher efficiency. | C.Lower cost. | D.Higher safety |
A.Science and Technology. | B.Nature and Health. |
C.Society and Environment. | D.Life and Business. |
【推荐1】Photos of a gentleman reading calmly in bed in the newly-built makeshift hospital in Wuhan, epicenter (中心) of the coronavirus outbreak, went viral on China’s social media platforms, with many calling him the “Invincible Wuhan Man”.
The man, dubbed “The Reader in Fang Cang” (mobile cabin hospital) has even garnered (获得) attention from the author of the book featured in the photo, The Origins of Political Order by Francis Fukuyama, on Twitter. Surnamed Fu, the 39-year old “invincible” reader is currently a teaching postdoc at Florida State University after obtaining his doctorate degree in Wuhan University. His hometown is in Xiaogan, a city neighbouring Wuhan, but his parents currently live in Wuhan. Fu was infected with novel coronavirus when he visited his parents, and he was among the first group of patients transferred to the cabin hospital at Wuhan International Conference and Exhibition Center on Feb. 5, according to Hubei Daily. He bought the book in Wuhan, and he likes reading, Fu told Hubei Daily. He was just reading the book out of interest and never anticipated that the photo would go viral.
As Fu gains more popularity, Fukuyama’s book has also become a hit. The Origins of Political Order quickly topped the recommended book list on China’s review site Douban on Feb 7. Netizens were charmed by Fu’s positive and calm attitude. “This picture of him reading in bed gives me strength and hope, I wonder if he is still available,” said one Weibo user.
“When you feel depressed, reading is one of the solutions to heal your inner pains. Sometimes doing exercises helps too,” said another netizen.
Authorities in Hubei province, especially its capital Wuhan, are resolute in the measures taken to make sure all people needing medical assistance are admitted to medical facilities for the novel coronavirus pneumonia.
1. What made Fu go viral?A.Living in the newly-built makeshift hospital in Wuhan. |
B.Posting a picture on China’s social media platforms. |
C.Publishing a book called The Origins of Political Order. |
D.Reading calmly in the hospital during an outbreak. |
A.To return to his hometown. | B.To visit his parents. |
C.To buy the book. | D.To help people in Wuhan. |
A.Humorous. | B.Ambitious. |
C.Caring. | D.Positive and calm. |
A.introduce the book The Origins of Political Order |
B.encourage readers to keep positive and calm during the coronavirus outbreak |
C.tell readers how to be an “Invincible Wuhan Man” |
D.analyse why the coronavirus broke out in Wuhan |
【推荐2】Chinese writer Can Xue, along with Japanese author Haruki Murakami, was reportedly named as the fourth-ranked candidate(候选人)to have the highest chance of winning the Nobel Prize for Literature in 2019.
Can, whose real name is Deng Xiaohua, was born in Changsha, Hunan in 1953. Not raised as a writer, she spent almost 20 years while being a worker, tailor and medical practitioner (从业者).Yet she never gave up on her passion, and in 1985 published her first novel Yellow Mud Street. Like her other works, it made use of symbolism. The book became known as the autobiography of her inner world. Such a work was not easily accepted or understood by Chinese readers during that period. But Can never stopped pursuing her own style.
Other representative works include Old Floating Cloud and The Barefoot Doctor. Some have been translated in other languages, while others have been selected as textbooks at world-class universities in the US and Japan. Her novel The Last Lover has been honored with the Neustadt International Prize for Literature in US, widely considered a prelude award for the Nobel.
Sharing a stylistic similarity with Franz Kafka, Can has been called the "Chinese Kafka" by permanent Nobel Literature Committee judge and renowned sinologist Goran Malmqvist. Malmqvist even believed Can could achieve more than Kafka, as she has already created more than 7 million words of literary composition.
Can responded she was unworthy of that level of praise, and she is just standing on Kafka's shoulders.
Though not understood by many Chinese, Can still writes in a way that combines Western and Chinese culture. But Can said many Western readers thought her works novel enough, as she praised the virtues of introducing Chinese culture to the West.
1. When did Can Xue publish her first novel?A.In 1953 | B.In 1973. | C.In 1985. | D.In 2019. |
A.Old Floating Cloud. | B.The Last Lover. |
C.The Barefoot Doctor. | D.Yellow Mud Street. |
A.Her works made use of symbolism. |
B.She introduced Chinese culture to the West. |
C.She won the Nobel Prize for Literature in 2019. |
D.Her works shared a similar style with Franz Kafka. |
A.Modest | B.Passive. | C.Mean. | D.Generous. |
【推荐3】A computer program has been used to predict how people are feeling when they type.
In a study participants were asked to type a particular phrase and the program then estimated if they were happy, sad and so on. Surprisingly it was correct 70 per cent of the time, and the findings could lead to smarter artificial intelligence in the future.
The study published in the journal Behavior and Information Technology was carried out by researchers at the Islamic University of Technology in Bangladesh, reports Live Science.
In the research 25 people ranging from 15 to 40 years old were asked to retype two paragraphs from Alice's Adventures in Wonderland written by Lewis Carroll. They also had to enter their emotional state every 30 minutes while doing their regular activities on the computer. This allowed the program an opportunity to understand how their emotions changed their typing style.
Moods tested were joy, fear, anger, sadness, hate, and shame. The result was that the program could identify(识别) a person' s mood correctly 70 per cent of the time. It was most successful in identifying joyfulness with an 87 per cent success ratio, while sadness was the least successful at 60 per cent. The researchers found that the participants were less likely to input (输入) data when they were in a bad mood, which may explain the inexactness of the second result.
However, the findings could have great importance for artificial intelligence, and it may allow computers to get along with us in a friendlier manner, “If we could build any system that is intelligent enough to communicate with humans that is, it can identify user emotions and change its behavior accordingly then using machines could be more effective and friendly.” the researchers wrote.
1. Who conducted the study?A.Lewis Carroll. | B.Islamic University of Technology. |
C.Live Science. | D.Behavior and Information Technology. |
A.Input words and emotional state. | B.Change their typing styles. |
C.Change their feelings frequently. | D.Show their natural feelings. |
A.People usually hide their unhappy feelings. |
B.The program cannot recognize sadness clearly. |
C.The program cannot calculate the data correctly. |
D.It's more difficult to collect data when people are sad. |
A.It helps people develop smarter machines. |
B.It helps people speed up their typing speed. |
C.It will inspire similar studies on people's mood. |
D.It clearly explains the relationship between mood and typing. |