A Family Activity in the Spring Festival

4 . Atomic shapes are so simple that they can’t be broken down any further. Mathematicians are trying to turn to artificial intelligence (AI) for help to build a periodic table of these shapes, hoping it will assist in finding yet-unknown atomic shapes.

Tom Coates at Imperial College London and his colleagues are working to classify atomic shapes known as Fano varieties, which are so simple that they can’t be broken down into smaller components. Just as chemists arranged element s in the periodic table by their atomic weight and group to reveal new insights, the researchers hope that organizing these atomic shapes by their various properties will help in understanding them.

The team has given each atomic shape a sequence of numbers based on its features such as the number of holes it has or the extent to which it bends around itself. This acts as a bar code (条形码) to identify it. Coates and his colleagues have now created an AI that can predict certain properties of these shapes from their bar code numbers alone, with an accuracy of 98 percent.

The team member Alexander Kasprzyk at the University of Nottingham, UK, says that the AI has let the team organize atomic shapes in a way that begins to follow the periodic table, so that when you read from left to right, or up and down, there seem to be general patterns in the geometry (几何) of the shapes.

Graham Nib lo at the University of Southampton, UK, stresses that humans will still need to understand the results provided by AI and create proofs of these ideas. “AI has definitely got unbelievable abilities. But in the same way that telescopes (望远镜) don’t put astronomers out of work, AI doesn’t put mathematicians out of work,” he says. “It just gives us new backing that allows us to explore parts of the mathematical landscape that are out of reach.”

The team hopes to improve the model to the point where missing spaces in its periodic table could point to the existence of unknown shapes.

“China would always provide important opportunities for global development, and the nation would remain committed to     1    (drive)economic globalization in a more open, balanced and win-win direction,” an official said on the sixth China International Import Expo(CIIE)on Sunday. In his speech on the CIIE, which opened in Shanghai, he mentioned that various nations should     2    (joint)seek development in the sluggish(迟缓的)global economic recovery.

“The CIIE, first     3    (hold)in 2018, serves as a platform for international procurement(采购), investment promotion and people-to-people exchanges,     4     has contributed to encouraging a new development pattern and global economic growth,” the official noted. He also expressed the     5    (expect)that the annual expo could function as a gateway to the new development pattern and presented new opportunities to the world with China’s fresh development. Additionally, he said the expo should fully play     6    (it)role as a platform for facilitating high-level opening-up and make the Chinese market     7     major one shared by the world, so that the whole world could benefit     8     win-win cooperation.

The official also     9    ( stress)Beijing’s efforts to advance opening-up with greater market opportunities,     10    (far)creating immense economic growth for the world.

7 . Fresh fish should have a mild smell. Strong fishy smells are the first signs to go bad. How do the fishy smells come from?

It can be several days from when the fish are caught to when they reach the supermarket. In that time, bacteria that grow naturally in fish start to consume a substance called trimethylamine N-oxide(TMAO)in fish. These bacteria change TMAO into trimethylamine (TMA), the substance responsible for the fishy smells. Bacteria in fish can also change lysine(赖氨酸)into cadaverine(尸胺), a substance that’s associated with breaking down the fish once they are caught and giving off fishy smell.

Chemical reactions can also lead to fishy smells. This happens through the oxidation(氧化)of fat. Fish are an important source of omega-3 fatty acids. When these fats are exposed to oxygen, they oxidize and break down into the substance that you can smell.

To slow down the fishy smell, what is beyond question is that the less time between when the fish are caught and when they reach the kitchen, the better. But today, fish are often flown across the globe. To keep smell-producing bacteria at bay, the fish must be frozen or kept at the low temperature possible as soon as they are caught and cleaned.

Controlling fat oxidation can function as well, especially for fattier fish species. While freezing slows bacterial growth, it does not stop fat oxidation. This reaction will occur as long as oxygen is present. Fatty fish are usually not frozen because, despite the cold temperature, they’re going to oxidize pretty fast unless they are stored in a low oxygen container. That’s why those species are often canned.

It’s also important to remember that smell is not always an indicator of safety, especially in processed fish products. “What you might consider the fishy smell may be a delicacy in another culture,” said Carl A. Batt, a professor of food science at Cornell University.

8 . It started with a bit of casual discomfort on the head, but after a week it had spread to the back of my neck, enough to lead me to my laptop. Annoying as it was, I was ________ to take up my doctor’s time with such a silly complaint and then have a wasted journey only to be informed that it would clear up by itself and that ________ would be of no use at all.

As soon as I’d tapped in ‘online self-diagnosis’, the search engine provided me with over 11.5 million results. And during the time normally spent in the clinic’s waiting room reading the Women’s Weekly, I was able to find a site that would provide a free ________ in the comfort of my chair, and with no need for an appointment,

I answered all the questions until I eventually reached a description exactly matching my ________. As I clicked on ‘More Information’, I was hit with what I’d never anticipated. The worst case scenario was complete hair loss. I couldn’t have been more ________.

I headed off to the doctor for what I thought would be a blood test but which turned out to be a valuable lesson in not ________ everything you read on the internet. It took him less than a minute to guess at and locate head lice (虱子). I was relieved to know that I would be ________ my hair, and horrified to know that it was being occupied.

I learnt my lesson, but for some the worry caused by ________ every ache has led to a new form of hypochondria (疑病症). Named ‘cyberchondria’ by the print media back in 2000, this particular condition has ________ greatly. Although most people’s main point of call is still the doctor’s surgery, it’s estimated that ________ worries are now the second most researched topic on the web. This is truly a serious concern when about 25%of the medical information online is thought to be ________.

Once upon a time, hypochondria required time and effort: you had to go to the library to research your diseases and ________ go through the books. Now it’s just a matter of a few clicks of a mouse. But while your doctor will make a diagnosis ________ your age, appearance and medical history, a search engine will rely simply on algorithms (算法). These come up with results graded according to popularity or numbers of key words. So the most highly ranked hits might actually be for very genuine disease, which are nonetheless extremely ________. One minute you think you’ve come down with the flu, the next you’re under attack from sub-tropical, flesh-eating bacteria. Time spent going to the doctor’s for ________ of mind suddenly seems fair enough.