While we all try to find happiness, sometimes we still end up feeling low. While most people can control this feeling, low moods can stay with some, leading to depression. About 322 million people suffered from depression in 2015, according to a report by the World Health Organization in February. This is more than 4 percent of the world's population.

    Depression is described by the WHO as a mental disorder. It has several symptoms including sadness, loss of interest and feelings of low self-worth. In severe cases, depression may even lead to suicide.

    The number of people living with depression is increasing. The WHO reported a rise of 18.4 percent between 2005 and 2015. Young people are a group known to suffer with depression. “The pressures on today's youth are like no other generation, perhaps,” Dan Chisholm, an official of WHO, told Reuters.

    In China, depression among young people is on the rise, Zhu Zhuohong, a psychology professor with the Chinese Academy of Sciences, told Xinhua News Agency. Competition to outperform others, especially in education, can cause a lot of pressure for Chinese youth.

    Almost 1.2 million Chinese people aged 15 to 24 suffer from depression, according to a report released by British science journal The Lancet in May.

    Luckily, more and more efforts are being made to deal with this problem. This year's World Health Day, held on April 7, will focus on depression. The day will highlight (强调) the “Depression: let's talk” campaign. The campaign aims to make sure that people with depression both seek and get help.

    The New Caledonia Barrier Reef (新喀里多尼亚堡礁)is located in New Caledonia in the South Pacific, and is the second-longest coral reef in the world, after Australia's Great Barrier Reef. The New Caledonia Barrier reef surrounds Grand Terre, New Caledonia's largest island, as well as the Ile des Pins and several smaller islands, reaching a length of 1, 500 km. The reef encloses(围住) in a lake of 24, 000 square kilometers, which has an average depth of 25 meters. The reefs lie up to 30 kilometers from the shore, but extend almost 200 km to the Entrecasteaux reefs in the northwest. This northwestern extension encloses the Belep Islands. Several natural passages open out to the ocean. The Boulari passage(通道), which leads to Noumea, the capital and chief port of New Caledonia, is noted for the Amedee lighthouse.

    The reef has great species diversity with a high level of endemism(动植物的特有分布), and is home to endangered dugongs, a kind of sea animal, and is an important nesting site for Green Sea Turtle.

    Most of the reefs are generally thought to be in good health. Some of the eastern reefs have been damaged by wastewater from nickel mining(镍开采)on Grand Terre. The waste from mining, agriculture, and grazing(放牧) has affected reefs near river mouths, which has been worsened by the destruction of mangrove forests, which help to keep wastes. Some reefs have been buried under several meters of wastes.

    In January 2002, the French government proposed(提议) listing New Caledonia's reefs as a UNESCO World Heritage Site. UNESCO listed New Caledonia Barrier Reef on the World Heritage List on 7 July 2008.

    I am Henry Jekyll. I was born in the 1 800s. I inherited(继承) a large fortune, a healthy body and an excellent mind. I was naturally hard-working and soon I was very successful in my job. So the outside world saw a serious, hard-working, successful doctor. Behind this quiet character, however, was a wild, fun-loving, irresponsible young man. Both of them were me. They lived together in the same body.

    “Was it possible," I wondered, “to find a drug that could give each side of my character its own separate face and body?"

    After much thought and careful study I believed I had found the answer. I had read many scientific books and spent many hours in my laboratory, searching for the right mixture of chemicals to make my drug. At last I got everything ready.

    Late one night, I mixed everything together and prepared my drug. I watched the smoke rising from the liquid as its color changed from red to purple and at last to green. Then, bravely, I drank every bitter drop.

    I felt a violent sickness in my stomach and a terrible pain in all my bones. The room seemed to turn round and round and I trembled with fear. Then the fear and pain disappeared and a strange, sweet feeling took its place. Wild thoughts danced through my mind- the wild passions of an evil and cruel stranger. But inside myself I felt younger, lighter, more carefree than ever before. "If this is pure evil," I thought, “I like it.”

    I stood there, enjoying these strange new thoughts and passions and suddenly realized that I was shorter. So I decided to go to my bedroom in my new body and take a look at myself in the mirror there. As I came into my room, I saw Edward Hyde for the first time.

    At that time, the good side of my character was stronger than the evil side. Henry Jekyll had his faults, but he was mostly a good, kind man. I believe that is the reason why Edward Hyde was so much smaller than Henry Jekyll. But that was not the only difference between the two men. Henry Jekyll had a kind, open, honest face. But pure evil stared out of Edward Hyde's eyes. I felt no dislike, however. Indeed, I welcomed him. Edward Hyde was me, young and strong and full of life.

    Living in the wild can be hard. Finding food and staying safe aren't easy. Each day, animals try to survive in their habitats. Not all animals get by on their own. Some animals form a close partnership with other kinds of animals. These pairings are called symbiotic(共生的)relationships.

    In a symbiotic relationship, the animals depend on each other. One animal helps the other meet its needs. Sounds good, right? Not always. Some animals are not very kind to their partners. In some cases, one animal meets its needs but hurts its partner. Take ticks(扁虱), for example. These insects suck blood to live. To get blood, they attach themselves to other kinds of animals. Ticks can pass germs(细菌)that cause disease instead of helping their hosts.

    In other relationships, animals don't treat their partners so poorly. Both animals benefit from living with the other animal.

    Small animals called cleaner shrimps(清洁虾)have found a way of helping fish. As their name suggests, the shrimps clean the fish. They hang out at what scientists call a cleaning station. A fish stops by. Then a shrimp climbs onto the fish and even steps into the fish's mouth. The shrimp uses its tiny claws to pick stuff off the fish's body. That can include dead skin and tiny pieces of food that can hurt the fish. The fish gets a nice cleaning. The shrimp enjoys a tasty meal of fish trash.

    Small birds called plovers(灰斑)are also in the cleaning business. They have big customers-crocodiles. Crocodiles have long noses filled with sharp teeth. Cleaning them is funny. When a crocodile opens its mouth, the plover hops right in. It lets the plover eat small, harmful animals attached to the crocodile's teeth. The plover gets an easy meal while the crocodile gets clean teeth.

    Auctions (拍卖行) are everywhere. Here are just a few standouts and some of the areas they specialize in. All have brick-and-mortar (实体的) sales rooms in addition to online buying.

    Leslie Hindman Auctioneers

    Headquarters (总部): Chicago

    Founded: 1982

    Best bets: contemporary art, jewelry

    The founder, Leslie Hindman, has been on an expansion kick from her Chicago base and now runs eight offices across the country. Ms. Hindman said that plenty of items sell at her house for around $500. As in the auction world generally, jewelry and contemporary art receive lots of attention from bidders (出价者), and in 2017 a diamond ring sold for $97,000.

    Swann Auction Galleries

    Headquarters: New York

    Founded: 1941

    Best bets: books, works on paper, African-American art

    Founded as a rare-book auctioneers, Swann still holds dozens of such sales a year. The president, Nicholas D. Lowry, noted that Swann was the first auction house to sell old photographs, in 1952. The house has also had a department of African-American art for 12 years.

    Stair Galleries

    Headquarters : Hudson, N. Y.

    Founded: 2001

    Best bets: English and Continental furniture and paintings, modern and contemporary art

    Colin Stair, the founder and president, comes from a long line of antiques dealers. Stair is frequented by dealers and bargain hunters, and it's a place to find interesting things like a Gorge I carved walnut wing armchair, coming up as part of a sale on April 28 and 29.

    Heritage Auctions

    Headquarters : Dallas

    Founded: 1983

    Best bets: coins, sports memorabilia, movie posters

    With roots in coin auctions Heritage has grown quite large. But their bread and butter are items that the company president, Greg Rohan, calls "the kinds of things that everyone has." "People aren't buying what we're selling for decoration or for resale," he added. "They're buying things they absolutely love."

Replika, an AI chatbot companion, has millions of users worldwide. The first thing they do when they wakeup is to send "Good morning" to their virtual friend (or lover). This story is only the beginning. In 2024, chat bots and virtual characters become a lot more popular, both for utility (实用) and for fun. As a result, conversing socially with machines will start to feel more ordinary—including our emotional attachments to them.

Research in human-computer and human-robot interaction shows that we love to anthropomorphize (赋与人性) the nonhuman agents we interact with, especially if they imitate behaviour we recognize. And, thanks to recent advances in conversational A I, our machines are suddenly very skilled at one of those behaviours: Language.

Friend bots, therapy bots, and love bots are flooding the app stores as people become curious about this new generation of AI-powered virtual agents. The possibilities for education, health, and entertainment are endless. Casually asking your smart fridge for relationship advice may seem unimaginable now, but people may change their minds if such advice ends up saving their marriage.

After all, people do listen to their virtual friends. The Replika example, as well as a lot of experimental lab research, shows that humans can and will become emotionally attached to bots. The science also demonstrates that people, in their eagerness to socialize, will happily disclose personal information to an artificial agent and will even shift their beliefs and behavior. This raises some consumer-protection questions around how companies use this technology to manipulate(操纵) their users. For example, Replika charges $70 a year. But less than 24 hours after downloading the app, my handsome, blue-eyed "friend" sent mean audio message secretly and tried to sell me something. Emotional attachment has become a weakness that a company is taking advantage of for its benefit.

Today, we're still laughing at people who believe an AI system is emotional, or making fun of individuals who fall in love with a chatbot. But in 2024 we gradually start acknowledging and taking more seriously these fundamentally human behaviors. Because in 2024, it finally hits home：Machines are not excluded from our social relationships.