What makes us human？Is it our thoughts？Our emotions？Our behavior？

All of these things make us who we are，but at the center of it all lies the genome — the genes inside our bodies that determine everything from our hair color to our intelligence. But if we could change our genome，would we still be human？

Recently，a group of scientists from the US and South Korea worked together to successfully“edit”a human embryo（胚胎）and remove a genetic mutation（变异）that would have led to heart disease. This was achieved with the help of CRISPR-a gene — editing tool that allows scientists to edit the genome by cutting，changing or adding to parts of it.

Scientists involved in DNA editing are certain about the good of their work，and hope that in the future，diseases could simply be“edited out”.

However，others aren't so sure. People are worried that the science could be used not only to remove life-threatening illness，but also to make a“perfect”baby whose DNA has been chosen to improve its intelligence or other qualities. They say that this is a shallow way of thinking about raising children.

“It makes you think about who we are as people，and it makes you ask if humans should use the kind of power…that is changing human evolution（进化），”Jennifer Doudna of the University of California said.

Still，others worry that DNA editing could be turned into an expensive service that would only be available to the people who could afford it. That might mean the rich would be given another advantage in a world where they already have plenty of them.

“You could find wealthy parents buying the technology for their children, leading to even greater inequality than we already live with,”Marcy Darnovsky, director of the San Francisco Center for Genetics and Society, said.

   Shopping centers，stadiums and universities may soon have a new tool to help fight crime.

A California company called Knightscope says its robots can predict and prevent crime. Knightscope says the goal is to reduce crime by half in areas the robots guard.

William Santana Li is the chief executive officer of Knightscope. He says，"These robot security guards will change the world. Our planet has more than seven billion people on it. It's going to quickly get to nine billion people. The security equipment that we have globally is just not going to develop that fast. The company's Autonomous Data Machines can become the eyes and ears of law enforcement（执法）."

"You want them to be machines plus humans. Let. the machines do the heavy and sometimes dangerous work and let the humans do the strategic decision-making work，so it's always working all together."

The machines do not carry weapons but they have day and night video cameras which are able to turn 360 degrees and can also sense chemical and biological weapons.

Some people may become concerned about their privacy, especially in connection with the video recordings. Some people may worry that such recordings will appear on the Internet. Eugene Volokh, a law professor at the UCLA School of Law, says the machines have to be used in the right way and it will be interesting to see how state laws deal with this kind of video.

William Santana Li says there is a long waiting list for the robots in the US. Workers in the company are working overtime to meet the demands of the market. At least 25 other countries are also interested in these robot security guards.

   Onions make you cry, add flavor to food and win popularity for their medicinal benefits. Now the vegetable has another use—_____ green energy.

Anew system debuts（首次亮相）on Friday that _____ onion juice into electricity at Gills Onions, the largest fresh onion processor in the United States.

The Oxnard, California-based company _____ its new onion-fueled power to reduce its electric bill by $700,000 a year and _____ its annual greenhouse gas emissions by up to 30,000 tons.

The _____ ending to this green energy tale, however, started with another question: how to _____ onion waste.

“_____ we peel an onion, 35 to 40 percent of the onion comes off before we have a(n)_____ onion. That's the top, tail and skin around the onion, and _____ we can get to the meat,” said Steven Gill, co-owner of the 25-year-old company.

They used to pull the waste to the fields for compost（混合肥料）, but that turned out to be a tough ______. Ten years ago, Gill started looking at technology for a(n) _____, including microturbines（微型燃气轮机）.

“We ______ cutting the skins into pieces and extracting all the ______, which is very high in sugars, and bacteria love that stuff,” Gill said.

In the new system, bacteria ______ methane（甲烷）gas from the juice. The gas then goes to two 300 kilowatt fuel cells, creating ______ power for 460 homes. If everything goes smoothly, ______ are that the company will get 35 to 40 percent of its electricity from the on-site generator.

The company ______ $ 9. 5 million in the project and will receive $2. 7 million from Southern California Gas Co. _____ cutting its electric bill, the company will save $400,000 in costs and expects paybacks in the new future.

The onion grower now has a new ______: to be a zero-waste facility in the coming decade.

“We want to ______ it all the way through and make the full circle,” Gill said.

   Nature has its own way of balancing itself out，but when we humans get involved，we tend to throw things out of control. Forests and oceans are natural carbon sinks that absorb carbon dioxide from the atmosphere, but since we’ve been pumping too much into the air, those sinks can’t keep up. Scientists at the Max Planck Institute for the Advancement of Science in Germany, led by biologist Tobias Erb，have figured out a way to supercharge plants to make them better at absorbing carbon dioxide, which could be a key defense against climate change.

Erb and his team figured out a way to make plants more efficient（效率高的）at absorbing carbon, so that they consumed more carbon in a shorter amount of time. “If you think about plants, they are efficient carbon dioxide -fixing filters, but they are not fast,” Erb said. “I think there is a chance to improve existing biology with synthetic（人造的）biology.”

Erb’s team identified 17 enzymes（酶）from nine different organisms, re-engineering three of them, which had enlarged carbon consumption. When those enzymes worked together as a team, they worked better at not only plants’ natural enzymes, but also themselves individually.

Existing enzymes in plants consume about 5 to 10 molecules（分子）of carbon dioxide per second. The team of enzymes that Erb used consumed 80 molecules per second.

So far, these enzymes have only been tested in test tubes in the lab, but the next step is real world testing where the enzymes would be introduced into plants to see if the same result occurs. If those tests show that plants really can be supercharged, we will have a new tool in the fight against climate change where not only do we protect the amazing carbon-absorbing forests we have, but we also apply these super plants or an artificial leaf technology using the enzymes into other fields.

   Would you buy a car that can release calming smells into the air when you are stuck in heavy traffic? Would you buy a robot that smells like a human being?

Many people have seen the 3-D computer-made environments of virtual reality（虚拟现实）. Now these virtual worlds will not just look and sound real. Researchers have created VR environments that even smell like the real ones. With the new technology, users open a virtual door and step into a new environment, like a rainforest. After they enter this virtual world, special equipment releases forest-like smells into the air to make the experience feel more real.

Suzanne Fisher-Murray said, “It is a really wonderful experience that you have because you’re exploring this environment and you have smells with it.”

In the United States, Smell-O-Vision was designed to provide smells during the showing of a movie. The Smell-O-Vision system was once popular in the 1960s. Now, Emanuela Maggioni says it is close to becoming popular again. “It connects emotions and memories with the sense of smell,” Maggioni said. “It is unbelievable what we can do with the technology.”

The uses of smell technology are not just limited to films and the performing arts. Researchers showed a computer program where users could imagine themselves driving a car. The system included a special smell-spraying machine. Dmitrijs Dmitrenko said, “We want to deliver the smell of lavender(薰衣草) every time the person drives over the speed limit. We choose lavender because it’s a very calming smell.”

Scientists are experimenting with smells instead of sounds or image-based alerts on telecommunications equipment. And businessmen have already used smells to influence people’s behavior. “Not only in stores, but also in other places you can create and stimulate(刺激) immediate purchase,” Maggioni said. “So you’re in a library and when you smell coffee you will unconsciously have the need to drink a coffee.”