Born in a poor American family, John Smith depended on scholarships     1     (pay) for his tuition fees when studying in a medical college. After graduation, he rejected an offer in New York, came to Wuhan and     2     (hire) by a local hospital. He held the principle that he should never complain about the working pressure but make positive responses     3     his patients in need.

He tended them     4     (careful), organized first aid lessons, and saved many people’s lives with his professional knowledge. That impressed a girl     5     was working in a local clinic. She fell in love with this caring doctor. Two years later, they got married. A decade later, he was elected chairman of the local medical association, the first foreigner in that position. This chain of events made him the     6     (happy) man in the world.

Then came the outbreak of COVID-19 in Wuhan. With the number of     7     (infect) patients increasing sharply, he helped carry these people through the disease together with many other medical     8     (worker). After     9     great deal of effort, the majority of the patients recovered. However, he himself was badly infected. Having fought against COVID-19 for a month, he passed away, leaving his family in tears and in despair.     10     (hear) the sad news, many people sent flowers to the hospital in memory of his contribution.

This year’s Nobel Prize in physiology or medicine has been awarded to Katalin Karikó and Drew Weissman for their work on mRNA vaccines,     1     crucial tool in limiting the spread of Covid-19. The Nobel Prize committee announced the extraordinary honor,     2    (see) as the summit (顶峰) of scientific     3    (achieve), in Sweden on Monday.

Karikó, a Hungarian-American biochemist, and Weissman, an American physician, are both professors at the University of Pennsylvania. The committee praised the scientists “groundbreaking findings”, which fundamentally changed our understanding of     4     mRNA and our immune system affect each other. They published their results in a 2005 paper    5     received little attention at the time, but later laid the foundation for     6     (critical) important developments that served humanity during the coronavirus pandemic,     7    (contribute) to the high rate of vaccine development.

Rickard Sandberg, a member of the Nobel Prize in medicine committee, said, “Because of mRNA vaccines and other Covid-19 vaccines, millions of lives     8    (save) in the past few years.” The revolutionary technology has opened a new chapter of medicine. It can potentially be made use of       9    (develop) vaccines against other diseases like malaria, RSV and HIV. It also offers a new approach     10     infectious disease like cancer, with the prospect of personalized vaccines.

5 . A quick increase of dopamine (多巴胺) shifts mice into a dreamy stage of sleep. In the mice’s brains, the chemical messenger triggers rapid-eye-movement sleep, or REM, researchers report in the March 4 Science.

These new results are some of the first to show a trigger for the shifts. Understanding these transitions in more detail could ultimately point to ways to treat sleep disorders in people.

Certain nerve cells in the ventral tegmental area of the mouse brain can pump out dopamine, a molecule that has been linked to pleasure, movement and learning, which is then delivered dopamine to the amygdalae, two almond-shaped structures deep in the brain that are closely tied to emotions.

Using a molecular sensor that can tell exactly when and where dopamine is released, the researchers saw that dopamine levels rose in the amygdalae just before mice shifted from non-REM sleep to REM sleep.

Next, the researchers forced the mice into the REM phase by controlling those dopamine-producing nerve cells using lasers and genetic techniques. Compelled with light, the nerve cells released dopamine in the amygdalae while mice were in non-REM sleep. The mice then shifted into REM sleep sooner than they typically did, after an average of about two minutes compared with about eight minutes for mice that weren’t prompted to release dopamine. Stimulating these cells every half hour increased the mice’s total amount of REM sleep.

Additional experiments suggest that these dopamine-making nerve cells may also be involved in aspects of narcolepsy (嗜睡症). A sudden loss of muscle tone, called cataplexy, shares features with REM sleep and can accompany narcolepsy. Stimulating these dopamine-making nerve cells while mice were awake caused the mice to stop moving and fall directly into REM sleep.

The results help clarify a trigger for REM in mice; whether a similar thing happens in people isn’t known. Earlier studies have found that nerve cells in people’s amygdalae are active during REM sleep.

Many questions remain. Drugs that change dopamine levels in people don’t seem to have big effects on REM sleep and cataplexy. But these drugs affect the whole brain, and it’s possible that they are just not selective enough.

8 . What was once science fiction is now a part of our everyday lives, as artificial intelligence (AI) is something that many of us live alongside. According to Statista, in 2019, 3.25 billion virtual assistants were used worldwide and that figure is predicted to be more than double by 2014.

AI is doing more for us than setting reminders, making recommendations, and offering us weather reports. In fact, it could be about to change the healthcare landscape entirely. It is estimated that one in eight people today use health apps regularly. And AI has more to offer.

Dr Emilia Molimpakis is a neuroscientist who co-founded thymia, a platform that uses AI powered games to help doctors spot depression.

“I was inspired to start thymia after seeing my best friend struggle with depression,” she says, “I saw her try to go through the psychiatric (精神病学的) system and fall through the cracks. Despite being seen by a psychiatrist, she ended up trying to take her own life. When that happened, I was the one who found her, and this experience impressed me.”

Aside from blaming herself for not recognizing the signs sooner, what she could not get her head around was how the psychiatrist should not see this coming. She realized that the tools psychiatrists used were still these old-fashioned, pen-and-paper questionnaires that have been found, time and again, to be subjective and not reflecting a patient’s actual mental health status. So, thymia was born.

But as we look into the future, what should we be aware of? Before we dive in head-first, there are still questions we need to answer. As Dr Molimpakis points out, it’s vitally important that AI tools used in healthcare must be trained on a diverse data set that is typical of all groups of people. It should also be used alongside, and in addition to, professional care—not as a replacement. We should also consider carefully how our health data is stored and used. These are topics that both users and professionals have a responsibility to consider.

9 . Paris Baker is a 30-year-old mother who has two daughters, Kallie, nine, and Harper, five.

One day, the three were playing at home. Harper was playing mom, feeding her mother, then her teddy bear and finally herself. Suddenly, Paris started choking on a piece of cookie. Soon, the cookie was at the back of her throat. The two girls started hitting her back at once. After about a minute of hitting her back, Kallie went to call an ambulance as she started to worry. As she did this the other girl carried on doing what she had been doing and thankfully the cookie finally came up.

Paris was diagnosed (诊断) with motor neurone disease (MND) in 2017, and was told she had five years to live. The condition will gradually paralyse (使……瘫痪) her, leaving her trapped inside her body.

Due to her condition, she’s more likely to fall and has received serious injuries. She felt it was very important to teach her girls what to do in a dangerous situation she might be in. This included applying pressure to a bleeding wound, what to do if someone is choking and how to call emergency services.

The girls know that if their dad isn’t home and an emergency happens there are three steps. Step one is to ring 999, ask for an ambulance and give their address. Step two is to put their dogs in the garden, and step three is to open the front door for the emergency services.

After the accident, Paris was so grateful that she had taught her daughters what to do in such a situation. But accidents like that can happen to anyone. So if your kid hasn’t learned first aid skills yet, it’s time to do that now.