1 . Chinese scientists have identified a new protein that restricts HIV infection, a discovery that could pave the way for the development of new drugs against the virus. The protein, P-selectin glycoprotein ligand 1 (PSGL-1), which exists in human cells, can inhibit (抑制) the process by which HIV reproduces, according to research published in the science journal Nature Microbiology this month.

However, the study also showed that PSGL-1 can be negatively affected by Vpu — an accessory (附属) protein of HIV — which can neutralize the ability of PSGL-1 to resist HIV. Further research is under way to develop a drug that can inhibit the HIV protein so that PSGL-1 can restrict HIV, according to Tan Xu, a researcher at Tsinghua University's School of Pharmaceutical Sciences, a leading author of the study.

Several other proteins in human cells that could resist HIV have been discovered over the past 10 years, but the virus can also evade (避开) them. PSGL-1 shows particular promise in that it can inhibit HIV in multiple ways — especially by blocking the infectiousness of virus offspring, Tan said.

“We are starting to research into small molecule (分子) compounds in the hope of finding one that can restore PSGL-1’s anti-HIV function. In this way, we can develop a very effective antiviral drug for people with HIV/AIDS,” he said. Tan said it will require at least three to five years for the research to reach the preclinical stage, and more time after that before a clinical trial is possible. The research was conducted by researchers at Tsinghua University in Beijing, Fudan University in Shanghai and George Mason University in the United States.

Existing treatment methods for people with HIV/AIDS, which mostly rely on a combination of different drugs, can prevent the disease from progressing but cannot cure it, and long-term use of drugs can result in drug resistance.

An estimated 37 million people in the world live with HIV, according to the Joint United Nations Programme on HIV/AIDS. The study provides new leads to developing antiviral drugs, Tsinghua University said in a statement.

2 . Many people think that the world is about to step into the fourth industrial revolution. This time, machines can do a lot of work in the charge of human beings, even better than human beings. In the future, the world can be more efficient and enjoy cheaper services, but unemployment will become more common.

It raises a troubling question for all of us — when will a machine be able to do my job? Katja Grace, a research associate at the University of Oxford’s Future of Humanity Institute, and her colleagues from the AI Impacts project and the Machine Intelligence Research Institute, have surveyed 352 scientists and compiled (汇编) their answers into predictions about how long it may take for machines to outperform humans on various tasks.

The good news is that many of us will probably be safe in our jobs for some time to come. The researchers predict there is a 50% chance that machines will be capable of taking over all human jobs in 120 years.

“One of the biggest surprises was the overall lateness of the predictions,” says Grace. “I expected the amazing progress in machine learning in recent years, plus the fact that we were only talking to machine learning researchers, to make the estimates earlier.”

“I am a bit sceptical of some of the timelines given for tasks that involve physical manipulation (操纵),” says Jeremy Wyatt, professor of robotics and artificial intelligence at the University of Birmingham. “It is one thing doing it in the lab, and quite another having a robot that can do a job reliably in the real world better than a human.”

Manipulating physical objects in the real world — figuring out what to manipulate, and how, in a random, changing environment — is an incredibly complex job for a machine. Tasks that don’t involve physical manipulation are easier to teach.

Perhaps the hardest jobs for machines to perform are those that take years of training for humans to excel at. These often involve intuitive (直觉的) decision making, complex physical environments or abstract thinking — all things that computers struggle with.

3 . With nations preparing to spend billions to redesign their cities with a new focus on cycling, it's worth remembering how the invention of the bicycle changed societies all over the world.

The person generally credited with inventing the modern bicycle was an Englishman named John Kemp Starley. In 1885, the 30⁃year⁃old inventor began experimenting in his workshop with a chain⁃driven bicycle featuring two much smaller wheels. When it first appeared at a bicycle show in 1886, his invention was regarded as a curiosity. But two years later, when the next model was paired with the newly invented rubber tire—which not only cushioned the ride but also made the new bicycle about 30 percent faster—the result was magic.

For a few years in the 1890s, almost anyone wanted to learn to ride, and almost everyone did. The sultan of Zanzibar took up cycling. So did the czar of Russia. But it was the middle and working classes around the globe that truly made the bicycle their own. For the first time in history, the masses were able to come and go as they pleased. No more need for expensive horses and carriages.

The rocketing demand led hundreds of new companies around the world to offer their own versions. At the Stanley Bicycle Show in London in 1895, about 200 bicycle makers exhibited 3,000 models. One of the biggest makers was Columbia Bicycles, whose factory in Hartford, Connecticut, could turn out a bicycle a minute thanks to its automated assembly line (流水线)—a pioneering technology that one day would become the backbone of the automobile industry. By 1898, a third of all patent applications in the US were bicycle⁃related.

The bicycle even improved the human gene (基因) pool. Newly liberated young people rode around the countryside at will, meeting up in distant villages. Women were especially enthusiastic. They abandoned their troublesome skirts and took to the road in groups. Marriage records in England show a marked rise in inter⁃village marriages during the bicycle craze of the 1890s.

7 . A Dutch company has developed technology to follow the movements and activities of cows. The high-tech system, powered by AI and motion sensors, is called “The Intelligent Dairy Farmer’s Assistant.” The company, Connecterra, launched the system in the United States in December after several years of testing and operations in Europe.

A device is put around the neck of the cow to record its movements. This information is then processed by a computer that uses AI to learn about the animal’s behavior over time. The system can tell farmers what the cow is doing in real time. This information can help predict when cattle get sick, become less productive or are ready for mating.

Richard Watson owns the Seven Oaks Dairy in Waynesboro, Georgia. He was one of the first American farmers to use the high-tech system.

“It can pick up whether the cow is eating, whether it is walking, whether it is drinking, whether it is laying down, standing up.”

Watson said the system is a big help because it is impossible for farmers to keep up with the activities of each cow individually. He added that having a computer identify which of his 2,000 cattle need attention could help improve farm productivity by up to 10 percent. He estimates this difference could greatly increase his profits.

“Just a 10 percent or five percent increase, or improvement in productivity, means hundreds of thousands of dollars to us, aside from the fact that we just want happier and healthier and more welfare in our animals, anyway.”

The founder and head of Connecterra is Yasir Khokhar. He says the idea for the system came while he was living on a dairy farm south of Amsterdam.

“It turns out the technology farmers use is really outdated in many aspects,” Khokhar told the Associated Press. He added that most of the technology that does exist is difficult to use. He says modern agriculture greatly needs new technology like this.

The company says information about the cows can be collected and seen on a cellphone or other mobile device. A text message can also inform farmers of concerns involving the animals.

8 . Hybrid cars, also called hybrid electric vehicles （HEVs）, are cars that use more than one source of energy to run. They differ from the majority of cars on the road today in several ways. The main difference is that HEVs run on gasoline and electricity. An HEV car has a battery-powered motor as well as an engine that runs on gasoline.

A hybrid car is a bit more expensive to produce than a regular car even though its engine is smaller. The reason for the greater expense is that the engine is more complex. It has specialized mechanisms that allow it to operate using gasoline and electric power. It also contains a computer that works differently from those of regular cars. Even though it is more expensive to purchase, it costs less to own than gas-powered cars. When an HEV car is at a stoplight or going at a speed below 15 miles per hour, its special computer tells it to run just on electric power. When the computer senses that the car needs more power, it puts the gasoline engine back to work. The computer is constantly deciding whether the car will use electricity, gas, or a combination of the two.

Because the HEV has electric power to help it run, it uses much less fuel than most cars. In fact hybrid cars are the most fuel-efficient cars that exist today. They can get from 50 to 60 miles per gallon on average. The high mileage saves money for the car owner and conserves precious supplies of petroleum. Hybrid cars help the environment in other ways too. For example, when

the HEV is using electric power, it does not send out poisonous smoke that pollute the air.

Despite the differences between hybrid cars and regular cars, HEVs offer the same feel as regular cars. They handle the same way and speed up and stop in the same way too. HEVs, though, are generally smaller than gasoline-powered cars. Their rounded, aerodynamic frame helps add to their fuel efficiency but unfortunately does not add to the amount of space inside the vehicle.