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More than 50 percent of the largest lakes in the world are losing water, storing less water than they did three decades ago, according to a new assessment published today in Science. The key causes are not surprising: The warming climate and unsustainable human consumption.

Lead author Fangfang Yao, a climate fellow at University of Virginia, and his team created a technique to measure changes in water levels of nearly 2,000 of the world's biggest lakes and reservoirs (水库), which represent 95 percent of the total lake water storage on Earth.

They used 250,000 lake-area pictures taken by satellites between 1992 and 2020 to survey the area of 1,972 of Earth's biggest lakes. They collected water levels from nine satellite altimeters (测高计) and used long-term water levels to reduce any uncertainty. For lakes without a long-term level record, they used recent water measurements made by newer instruments on satellites. Combining recent level measurements with longer-term area measurements allowed scientists to reconstruct the volume of lakes dating back decades.

The result was staggering: 53 percent of lakes globally experienced a decline in water storage. The authors compare this loss with the size of 17 Lake Meads, the largest reservoir in the United States.

To explain the trends in natural lakes, the team used recent advancements in water use and climate modeling. "Climate change and human water consumption were mainly responsible for the global net decline in natural lake volume and water losses in about 100 large lakes," Yao said. "And many of the human and climate change footprints on lake water losses were previously unknown, such as the dryness of Lake Good-e-Zareh in Afghanistan."

And their research offers an understanding into possible solutions. Yao said, "If human consumption is a large cause of lake water storage decline, then we can adapt and explore new policies to reduce large-scale (大范围) declines." This happened in one of the lakes the team studied, Lake Sevan in Armenia. Lake Sevan has seen an increase in water storage, in the last 20 years, which the authors linked to the enforcement (实施) of conservation laws on water withdrawal since the early 2000s.

Researchers have trained a robot "chef" to watch and learn from cooking videos, and recreate the dish itself.

Grzegorz Sochacki, a PhD in Bio-Inspired Robotics Laboratory, and his colleagues designed eight simple salad recipes and filmed themselves making them. They then used a publicly available neural network (神经元网络) to train their robot chef. The neural network had already been programmed to identify a range of different objects, including the fruits and vegetables used in the eight salad recipes.

Using computer vision techniques, the robot analyzed each frame (画面) of videos and was able to identify the different objects and features, such as a knife and the ingredients (佐料), as well as the human demonstrator's arms, hands and face. Both the recipes and the videos were changed to vectors (模型) and the robot performed mathematical operations on the vectors to determine the similarity between a demonstration and a vector. By correctly identifying the ingredients and the actions of the human chef, the robot could determine which of the recipes was being prepared. The robot could infer that if the human chef was holding a knife in one hand and a carrot in the other, the carrot would then get cut up.

Of the 16 videos it watched, the robot recognized the correct recipes 93% of the time. The robot was also able to detect that slight changes in a recipe, such as making a double portion (份) or normal human errors, were changes and didn't mean a new recipe. The robot also correctly recognized the demonstration of a new, ninth salad, added it to its cookbook and made it.

"Our robot isn't interested in the sorts of food videos that are popular online, which quickly move back and forth between the person preparing the food and the dish they're preparing—they're simply too hard to follow," said Sochacki. "But as these robot chefs get better and faster, they will be able to use those videos to learn a whole range of recipes."

On April 10, the University of Utah became officially Bee Campus certificated. This process was started by senior Zoē Bross in her second year on campus. Bee Campus USA hopes to protect the native pollinators (传粉者) on college campuses by increasing the number of native plants, providing nest sites, reducing the use of pesticides, and offering educational opportunities that help with pollinator conservation.

After first hearing her school wasn't certificated a Bee Campus and finding becoming Bee Campus certificated would give the University more point s on the Advancement of Sustainability in Higher Education Sustainability Tracking, Assessment & Rating System (STARS) program, which decides ratings to campuses according to their sustainable efforts, Bross wanted to help.

There are many requirements to become Bee Campus certificated. The first major step for Bross was to create a standing Bee Campus committee with a mix of students and staff. Bross tried to reach out to professors and people specializing in this field. After many efforts, the program was finally passed through and a garden for it was created.

Over 100 people showed up to help plant in the garden. After the planting was done, Grounds, responsible for planting the pollinator gardens, set up their hydroseeder (水力播种机) and let attendees take turns spraying the hill, with a mixture of water and wildflower seeds, making the area more pollinator-friendly. Rocky, the school robot, even made an appearance, taking turns spraying.

Certificated by Bee Campus USA, Bee Campuses are expected to continue maintaining or improving pollinator habitats on campuses, as well as maintaining an educational online presence. "I see the campus continuing to be very interested," Bross stated.

Future plans for the campus include more pollinator gardens, native wildflowers, and even bee sculptures to provide new habitats. As for Bross? She pictures herself somewhere warm and sunny in the near future, working in environmental communications and doing something for the change she wants to see in the world.

A school Picture Day usually occurs either once in the fall, or twice a year during both the start of the fall and spring terms. A school Picture Day is you and your children's chance to record and keep memories for the school year. Missing a Picture Day means missing out on joy and special moments of the childhood—so it's important to plan ahead.

Hairstyle

Don't get a new haircut right before the Picture Day. If you're planning your children's haircut for the Picture Day, make sure it gets done at least two weeks before the Picture Day. This will ensure that any bad spots have time to grow back before the photos.

Try to stick to a neutral haircut. Recent trending hairstyles, colors and other unique hairstyles may not go well. You should find a hairstyle that is both neutral and something that represents your children's personality.

Keep the hair out of their face. If your children's hair naturally falls in front of their face, try to use hairpins, hair spray, or even a fresh haircut to keep their bright smile shining through.

Clothing

Dress for the weather. If it's cold outside, you should make sure your children arrive at school in clothing that keeps them warm. On the contrary, if the Picture Day is scheduled on a forecast heatwave, dressing your children in warmer clothing (even if it's your favorite one) could result in sweat showing up in the photos.

Don't make your children wear anything they don't like. They'll shine in clothing they're comfortable in, but will look obviously less comfortable in one they don't like. Help your children show their best side by letting them wear clothes they love.

Accessories (配饰)

Keep jewelry minimal. You never want children's jewelry to distract from their photos. If they do want to wear some sort of jewelry, make sure that it's small or understated.

Avoid hats. Hats do little help, other than covering up your children's head and face and should never be included.

A Train in a circus.    B. Go to the farm.    C. Buy some animals.

1. 活动目的； 2. 演习经过及体会。

参考词汇: 消防演习 fire drill;

灭火器extinguisher

My mother made me what I am. She gave me the greatest gift a mother can give — the desire to excel (超越). She taught me to read before I was four. She also encouraged me to write. When I was 10, I wrote a story and she sent it to a children's magazine. They accepted it and paid me some money. So I started earning money by writing at a young age.

I also learned a lot from my father. He'd say, "Stand tall, be independent and keep your eyes open." For what, I don't know! He was quite good at telling stories, and I think I inherited my gift for storytelling from him. But he could be pretty strict. If I went out with a boy, he had to pick me up from home so my father could question him inside out.

My father was 6 feet tall and good-looking, with great charm. He lost a leg m the war while serving in the Royal Navy, but never let it hold him back. When he was in hospital, ready to have his leg amputated, he said, not depressed, "Well, half a loaf is better than none." After his death, I returned his artificial leg to the hospital, but walked away in tears. It felt as if I was giving part of him away.

My parents had a son, Vivian, who died before I was born, so my mother put all her love into me. She also gave me an. education I couldn't get at school. She took me to the pictures every week, to the theatre to see the Russian ballet whenever it came to Leeds, where we lived.

At 20, I moved to London to become fashion editor of Woman's Own and later a columnist on the London Evening News. The day I left home, my mother wrote in her diary that all the sunshine had gone out of her life when her daughter left home.

We say that technology is a double-edged sword—while it brings convenience, it also brings new problems. The sword of "social media" even has a gender preference in its damage. It cuts deeper into girls than boys.

Earlier studies have shown that spending too much time on social media is bad for teenagers'mental health. Constantly watching their friends show off "perfect" lives can hurt their own self-esteem. That's not to mention the problems caused by online shaming and bullying.

Jean Twenge, a professor at San Diego State University in the US, recently discovered an alarming trend: Since 2010, the number of teenage girls who suffer from major depression—showing signs like self-harm and suicide—has increased much faster than that of boys. In an article she wrote at The Conversation, Twenge said social media, again, was to blame.

For starters, girls use social media more than boys. Boys tend to spend their screen time on games, where they talk to their teammates through headphones. This counts as real human contact. Girls, however, simply type and browse through posts, which is a much isolated experience. "They're not having a real-time conversation with someone," Mary Fristad, psychologist at The Ohio State University, told NPR.

And when it comes to online shaming, girls are also more vulnerable than boys. "Girls face more pressure about their appearance, which could be exacerbated (加重) by social media," wrote Twenge.

Shannon McLaughlin, for example, is an 18-year-old from Blackburn College in the US. She shared with the Guardian how social media made her feel depressed. "I was constantly confronted by women with skinny bodies who were praised for the way they looked. This was only made worse by the diet fixes and skinny culture," she said. But McLaughlin found a solution. She started volunteering with the National Citizen Service, where she made face-to-face contact with people. "It's so easy to forget the importance of real connections when we have hundreds of people that we're trying to impress at our fingertips," she told the Guardian. And she hopes that others "look up from their phones and focus more on the world around them".

While learning the science lessons, I used to get a doubt—why ears, nose, tongue and eyes should be called as special senses? The basic reason is that these are the channels through which we maintain contact with the surroundings. Though apparently it may feel like these are individual sensory organs, they do show some connectivity. Interestingly, our hearing is less sharp after we eat a heavy food. Isn't it good for a sound nap after a stomach-full meal? That does not mean we go deaf after a meal, but the hearing pitch (强度) does change after a heavy meal.

We usually give credit of the taste to our tongue, but do you know that unless saliva (唾液) dissolves something, our tongue cannot recognize the taste of the food eaten. Taste is nothing but the food chemicals dissolved in the saliva being sensed by the taste buds present on the tongue. Try to dry off your tongue and mouth with a tissue paper and then taste something.

Women are much better smellers than men. They are born with this characteristic ability and can correctly pinpoint the exact fragrance of the sample. We all can store almost 50, 000 different scents (气味), which are strongly tied to the memories. 

Pupils (瞳孔) do not respond to light alone, but to the slightest bit of noise around too. Thus surgeons, watchmakers and those professionals who have to perform a much delicate job do prefer to have a sound-free environment. Even a small noise can dilate (扩大) their pupils, change the focus and blur (使模糊) their vision. If you do not wear glasses or contact lens due to having a 6/6 vision, you are just among the one third of the human population. It is now statistically proved that only one third of the population has perfect vision, rest all are either wearing glasses or are trying to read with a compromised vision. 

Each and every one of us has a particular or individualistic or characteristic smell, which is unique to us, except for the identical twins. This smell is very subtle (微妙的) yet can be sensed even by a newborn. It may be due to this scent that the newborn recognizes the presence of his parents around. Many of us can pinpoint the smell of our significant friends and colleagues. A significant part of this phenomenon is guided by genetics but it is also changed by the environment, diet and personal hygiene. This all together creates the unique chemistry that is individualistic for each person.

I had not hugged a friend or a family member for more than two years until recently when my sister-in-law flew in for a brief visit. For everyone's safety, we met outside. Despite the wintry weather, her hug warmed me from the inside out. It's strange, but only now do I truly realize how much I've missed embracing loved ones—the warmth that remains long after our arms have untwined (松开).

Growing up through war in my hometown of Sarajevo, Bosnia, every moment was full of danger. On one peaceful morning, I had begged my mom to let me go outside after spending weeks wilting (蔫) indoors. She finally agreed. I was outside for only 10 minutes when I was caught in an explosion. I ran to my neighbor's house for safety and draped (悬挂) my arms around her neck just as my legs collapsed (瘫倒) underneath me. She hugged me with both arms and dragged me into her house. I was still in her arms when the ambulance arrived.

Thankfully, I made a full physical recovery, but the emotional scars never left me. Years later there was another explosion near my house. I was safely inside, but my father had left to buy a loaf of bread. He had only just missed the blast. When he came back inside, I gave him the biggest hug imaginable. I was caked in tears as I held him tight.

That same night my parents managed to arrange my escape from our war-torn city. They desperately wanted at least some of my childhood to be normal. I was 16 and came to America on my own. A generous host family took me in and I began learning English and going to school. They had a large dog called Oscar. Over the next several months, I secretly struggled with feeling homesick and worried about my family back home. Despite managing quite well at school, I couldn't express my feelings. The only way I shared how I felt was by giving Oscar a big hug.

It is yet another sad aspect of our pandemic lives that hugging a stranger is the last thing on our minds. For many of us, even hugging a relative or a friend comes with stress and anxiety over risks and precautions (防范). Perhaps we have undervalued the impact of a simple hug. As I look back on my past, I count myself truly lucky to have been held, shielded and encouraged at some of the most key moments of my life by the almost otherworldly (超世俗的) power of a hug. I pray that in the not-so-distant future we can safely hold one another again -a friend, relative, or even a stranger.

London is a huge city with more things to do than anywhere else. With the London Pass, you get free entry to over 50 specially selected places with one purchase. In the list you'll find:

• 19 historic buildings

• 22 museums and art galleries

• 8 tours, cruises and walks and entertainment activities

• 13 places of interest including boats and aquariums

• 12 restaurants and services

The London Pass not only offers great value and convenience, but also enables you to beat the queues at selected attractions. There are also special offers such as discounts at restaurants and theaters, where the attraction is normally free to the public. The London Pass also gives you great offers such as a free guided tour. So whether you prefer museums or cinemas, galleries or ice skating or zoos, with The London Pass there really is something for everyone.

You can buy Adult or child passes for 2, 3 or 6 days. See all ticket prices bellow and choose what you need.

You can contact us by sending emails or making calls. Please call 1-888-254-0637. Outside the US please call 00-800-84468370 or+ 1210 507 5997.

VIP reservations: Contact a Customer Service representative at 1-866-270-2849.

NOTE: If your reservation is made prior to November 15^th, 2020 email sales@previewhotels.com.