Bill Gates recently predicted that online learning will make place-based colleges less significant, and five years from now, students will be able to find the best lectures in the world online. I applaud Mr. Gates. But what's taking us so long?

    As early as 1997, MIT(麻省理工) decided to post videos of all university lectures online. for free, for all people. But today, how many students have you met who mastered advanced mathematics or nuclear physics from an MIT online video? Unfortunately, the answer is not many. The problem is the poor quality of online education websites and the experience they provide to students. Those who go to the MIT website and watch courses online are surely very smart people, but it's not like playing a video game such as World of Warcraft. Only the most ardent students, those who are highly motivated, will devote themselves to studying these boring online videos.

    The real question is why we aren't spending more to develop better online education platforms. Where is the Avatar of education? Think about this. The market for Hollywood films per year is worth around 30 billion USD. Education in the world is a trillion-dollar-a-year market, hundreds of times bigger than Hollywood movies. Yet the most expensive digital learning system ever built cost well under 100 million dollars.

    Bill Gates' prediction is going to happen. There is no doubt about it. But it will only happen when we create high level educational content and experiences that engage and excite more than has ever been possible in the real world.

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    Are you interested in some of the most popular brands such as Beats headphones, True Religion jeans, and UGG shoes? They are also expensive. But some experts say they are not much better than cheaper brands.

    For example, Jim Wilcox works for Consumer Reports. He tested all kinds of headphones. He says that $80 Koss Pro headphones provide basically the same quality and comfort as Beats. So why do people pay twice or even 10 times as much for the hottest brands?

    Experts say it's because fashionable, expensive brands send a message. Brands say “I belong” or “I can afford it.”

    Some people think that expensive brand names are worth the price. They say that some designer clothes are really top quality and that they last longer than cheaper brands. Some teenagers choose to wear popular brands because these brands make them feel good about themselves.

    Alexandra Allam, 17, likes to buy brand-name products. “I'd rather spend the extra money to get something I know I'll be satisfied with,” she says. Her friend Emmy Swan agrees, saying “As long as you can afford it, it seems reasonable to buy what you want.” But not all teenagers agree. “Spending hundreds of dollars for designer sunglasses is stupid and unreasonable,” says Daniel Steinbrecher, 16. “It's fake (假的) happiness.”

    People who are against wearing expensive brand names say that many designer brands aren't any better. “It's wasteful to buy things just because they are popular,” says Edmund Williams, 15. “You'll feel better if you buy things because you like them. If you have extra money to spend, it would be better to give it to people in need.”

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    We've all been there: in a lift, in line at the bank or on airplane, surrounded by people who are, like us, deeply focused on their smartphones or, worse, struggling with the uncomfortable silence.

    What's the problem? It's possible that we all have compromised conversational intelligence. It's more likely that none of us start a conversation because it's awkward and challenging, or we think it's annoying and unnecessary. But the next time you find yourself among strangers, consider that small talk is worth the trouble. Experts say it's an invaluable social practice that results in big benefits.

    Dismissing small talk as unimportant is easy, but we can't forget that deep relationships wouldn't even exist if it weren't for casual conversation. Small talk is the grease (润滑剂) for social communication, says Bernardo Carducci, director of the Shyness Research Institute at Indiana University Southeast. "Almost every great love story and each big business deal begins with small talk," he explains. "The key to successful small talk is learning how to connect with others, not just communicate with them."

    In a 2014 study, Elizabeth Dunn, associate professor of psychology at UBC, invited people on their way into a coffee shop. One group was asked to seek out an interaction(互动) with its waiter; the other, to speak only when necessary. The results showed that those who chatted with their server reported significantly higher positive feelings and a better coffee shop experience. "It's not that talking to the waiter is better than talking to your husband," says Dunn. "But interactions with peripheral(边缘的) members of our social network matter for our well-being also."

    Dunn believes that people who reach out to strangers feel a significantly greater sense of belonging, a bond with others. Carducci believes developing such a sense of belonging starts with small talk. "Small talk is the basis of good manners," he says.

    Youth volunteers from Beijing University visited Song tang Hospital, a care clinic for the aged and dying patients, during the second Global Youth Service Day on April 21．

    Thirty student volunteers from the university's School of International Studies sat at the beds of the patients in their specially decorated “care huts”. They talked with them and gave massages （按摩）to patients kept in their beds.

    I felt sorry that I could not offer more to these people than talking with them and trying to cheer them up, said Deng Yetao, 20, a third - year student. “But it occurred to me that they need more care and love than babies. They are afraid of the coming death. Their loneliness is worse than physical pains.”

    “Even though they are suffering a lot, the majority of the elderly people want to talk to us. Each of them has a lot of life experiences and philosophies to share. Instead of doing them a favor, I felt I was gaining a valuable lesson. Said Mao Xiaohua, another third - year student.

    Mao talked with two elderly patients for a whole afternoon. The fact that most of the patients in the 80 - room clinic are aged people with diseases which will lead to death soon made the volunteers' hearts heavy.

    Ninety - one percent of the patients will spend the last days of their lives in the clinic, according to a survey by the hospital.

    Daily visits and services by social workers and youth volunteers are a very important part of their programmer. A total of 330, 000 Beijing students from 119 universities and colleges have visited the hospital. Many continue to offer services in their spare time. Some of them volunteer to hold the hands of dying patients during the last minutes of their lives.

    Yin Hang, a student from Beijing Medical College, said he felt“ the glory of life” as he saw the fading smile on the face of the old man who passed into a deep unconsciousness（昏迷）while he was holding his hands.

    This year is considered as one of the hottest on record, but a genius cooling device in a tiny package is helping many to beat back the heat. Hundreds of thousands of people around the world have already experienced the power of it.

    What is It?

    The device is ZenCooler developed by two German engineers who were tired of the increasingly hot and punishing weather. They realized that regular air conditioning technology was a far from the ideal solution, proving to be too inefficient, and expensive to be used practically on a daily basis. Therefore, they developed the new device that is both sleek, easy-to-use, and extremely powerful. Best of all, it's no bigger than the size of a lunchbox.

    How does ZenCooler Work?

    Simply fill it with water, plug it in and turn it on. Powered by a USB cable, it can be literally run off your smartphone, power bank, and laptop. In less than 60 seconds, you will be enjoying all the benefits of a ZenCooler air-conditioned room.

    The Best Value for Your Money

    With most AC units costing upwards of $200 bare minimum, all the way up to thousands when you take installation and maintenance into consideration, ZenCooler is really a no brainer for the value you're getting. Right now, you can enjoy all the benefits and savings that Zencooler offers, for an all-time low price of only $89/unit which is an absolute steal when you are thinking about everything you're getting!

    If that's not enough of a bargain, they are also offering multi-buy discounts for as low as $49/unit available now.

    Where can you buy ZenCooler?

    Right now it's only available from ZenCooler's official website. Order now to lock in the best price! Click here to order your ZenCooler today.

 Imagine this. You need an image of a balloon for a work presentation and turn to an AI text- to- image generator, like Midjourney or DALL-E, to create a suitable image. You enter the prompt(提示词)" red balloon against a blue sky" but the generator returns an image of an egg instead.

What's going on? The generator you' re using may have been" poisoned". What does this mean?

Text- to- image generators work by being trained on large databasets that include millions or billions of images. Some of the generators have been trained by indiscriminately (任意地) scraping online images, many of which may be under copyright. This has led to many copyright infringement(侵害) cases where artists have accused big tech companies of stealing and profiting from their work.

 This is also where the idea of" poison" comes in. Researchers who want to empower individual artists have recently created a tool named" Nightshade" to fight back against unauthorised image scraping. The tool works by slightly changing an image's pixels(像素) in a way that confuses the computer vision system but leaves the image unchanged to a human's eyes. If an organization then scrapes one of these images to train a future AI model, its data pool becomes" poisoned". This can result in mistaken learning, which makes the generator return unintended results. As in our earlier example, a balloon might become an egg.

 The higher the number of" poisoned" images in the training data, the greater the impact. Because of how generative AI works, the damage from" poisoned" images also affects related prompt keywords. For example, if a" poisoned" image of a Picasso work is used in training data, prompt results for masterpieces from other artists can also be affected.

 Possibly, tools like Nightshade can be abused by some users to intentionally upload" poisoned" images in order to confuse AI generators. But the Nightshade's developer hopes the tool will make big tech companies more respectful of copyright. It does challenge a common belief among computer scientists that data found online can be used for any purpose they see fit.

 Human rights activists, for example, have been concerned for some time about the indiscriminate use of machine vision in wider society. This concern is particularly serious concerning facial recognition. There is a clear connect ion between facial recognition cases and data poisoning, as both relate to larger questions around technological governance. It may be better to see data poisoning as an innovative(创新的) solution to the denial of some fundamental human rights.