A team of engineers at Harvard University has been inspired by Nature to create the first robotic fly. The mechanical fly has become a platform for a series of new high-tech integrated systems. Designed to do what a fly does naturally, the tiny machine is the size of a fat housefly. Its mini wings allow it to stay in the air and perform controlled flight tasks.

     “It's extremely important for us to think about this as a whole system and not just the sum of a bunch of individual components (元件),” said Robert Wood, the Harvard engineering professor who has been working on the robotic fly project for over a decade. A few years ago, his team got the go-ahead to start piecing together the components. “The added difficulty with a project like this is that actually none of those components are off the shelf and so we have to develop them all on our own,” he said.

    They engineered a series of systems to start and drive the robotic fly. “The seemingly simple system which just moves the wings has a number of interdependencies on the individual components, each of which individually has to perform well, but then has to be matched well to everything it's connected to,” said Wood. The flight device was built into a set of power, computation, sensing and control systems. Wood says the success of the project proves that the flying robot with these tiny components can be built and manufactured.

    While this first robotic flyer is linked to a small, off-board power source, the goal is eventually to equip it with a built-in power source, so that it might someday perform data-gathering work at rescue sites, in farmers' fields or on the battlefield. “Basically it should be able to take off, land and fly around,” he said.

    Wood says the design offers a new way to study flight mechanics and control at insect-scale. Yet, the power, sensing and computation technologies on board could have much broader applications. “You can start thinking about using them to answer open scientific questions, you know, to study biology in ways that would be difficult with the animals, but using these robots instead,” he said. “So there are a lot of technologies and open interesting scientific questions that are really what drives us on a day to day basis.”

In the latest beauty craze(狂热)sweeping social media in China，women--and even some men--are boasting that they are paper thin，by posting photographs of their waists behind a vertical(垂直)piece of A4 paper．To qualify，the waist must be entirely hidden by the paper．A piece of A4 paper is 8.3 by ll.7 inches，roughly the size of a sheet of American letter paper．

    With the A4 Waist，the trend is attracting hundreds of photographs and thousands of comments on Weibo and other social media networks like Weixin or WeChat．Being abnormally thin is a widespread standard of beauty for women，one that has been criticized as an unhealthy ideal of female attractiveness．

    The tiny waist has a long tradition in China，going back at least to King Ling of Chu，who ruled from 540 to 529 B．C．Many in China know the passage from the Book of Han，the history of the Western Han Dynasty：“The King of Chu loved a narrow waist．Many people at court starved to death．

    Several commentators have found the A4 trend disturbing．In a telephone interview，He Xiaobin，senior fashion features editor at the Chinese edition of GQ magazine，said，“I find it completely stupid．Everybody has a different frame and body shape．Using a single size to define all human beings and thinking you have created a new standard is foolish．''The A4 waist challenge annoyed him，saying that it allows certain people to gain bragging rights，while leaving others in depression．

    Luckily，some who do not qualify are turning to humor for comfort．Can they substitute a different paper size，such as A3，which is 11.7 inches across Or measure a body part besides the waist?

    Most animals on land are known to us, but many living things underwater are not. Now let's get to know some of them.

    Sea cucumber

    Sea cucumber are strange animals living at the bottom of the sea. They wear brown or white green coats. When summer comes, they stay deep to sleep because they are afraid of heat. And when it is autumn, they move to shallow (浅的) water and get their food.

    Pike

    The pike is a kind of freshwater fish. They are good swimmers and like swimming near boats, waiting to be fed. They have sharp teeth to catch fishes. When they are young, they live in groups. However, when they grow up, they prefer to live alone.

    Cuttlefish

    A cuttlefish can swim quite fast, so it is also called rocket (火箭) fish. It has eight arms and two feelers on its head, just around its mouth. It ejects ink (喷墨) when it is in danger. Its meat is delicious, and it is often the first choice for many people.

    Octopus

    An octopus has long arms, with which to catch food and protect itself. When it is sleeping, one or two of its arms are still on duty, keeping moving. Once it feels something dangerous, it can wake up at once to take action.

    Public Health England (PHE) is targeting pizzas, ready meals, ready meat and takeaways. The government has also required the food industry to start using healthier food and encourage the public to opt for lower calorie foods.

    It is all part of an effort to cut calorie (卡路里) intake by 20% by 2024. The target will point to 13 different food groups, which are equal to about a fifth of the calorie taken by children. If action is not taken, PHE said, it would be prepared to ask the government to pass laws.

    PHE would be strictly monitoring progress by looking at which products people were buying and would be prepared to punish companies which do not take their duties. The government is also organizing a program encouraging adults to consume (消耗) 400 calories at breakfast and 600 each at lunch and dinner.

    At present, adults consume between 200 and 300 calories more than they should each day. PHE chief nutritionist Dr Alison Redstone said the 400-600-600 tip would make it easier for "people to make healthier choices" by being able to judge what they should be eating in each sitting.

    How many calories should we eat? It is suggested that women eat no more than 2,000 calories a day, while men should limit their intake to 2,500. For children, it depends on age. A four-year-old should consume no more than 1,300, while for teens aged 17 and 18, it is about 3,000, but overweight children are eating up to 500 calories more than that.

    Prof Russell Viner, of the Royal College of Pediatrics and Child Health, said it was a necessary move. He said, "Over the past 40 years, there had been a slow growth in food sizes, with pizzas and hamburgers simply much bigger than they were in our parents' time." The convenience of fast food at pocket money prices and the advertisement of unhealthy food and drinks to children add to the problem.

Dickens House Museum

Type: Historic House / Palace

Address: 2 Victoria Parade, Broadstairs, Kent, CT10 1QS

About

Dickens House Museum, Broadstairs celebrates Charles Dickens' long connection with Broadstairs from 1837 to 1851, through personal items and letters. Guided tours available.

The museum is housed in the cottage that was Charles Dickens' inspiration for the home of Betsey Trotwood in David Copperfield. David's description of Betsey's cottage with its square gravelled garden full of flowers, and a parlour of old fashioned furniture still fits today.

The character Betsy Trotwood is based on Miss Mary Pearson Strong who lived in the cottage that is now the museum. According to the reminiscences of Charles Dickens' son Charley, he and his father regularly had tea and cakes in the parlour (会客室) with the kindly and charming Miss Mary Pearson Strong. He also remembers that Miss Pearson Strong was completely convinced of her right to stop the passage of donkeys along the cliff top in front of her cottage. This belief became the donkey incident for the character of Betsy Trotwood, with the famous quote: "Janet! Donkeys!"

Spread over four floors, the Charles Dickens Museum holds the world's most important collection of paintings, rare editions, manuscripts, original furniture and other items relating to the life and work of Dickens. Perhaps the best-known exhibit is the portrait of Dickens known as Dickens' Dream by R. W. Buss, an original illustrator of The Pickwick Papers. This unfinished portrait shows Dickens in his study at Gads Hill Place surrounded by many of the characters he had created.

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How to Start a Garden in 2024?

Gardening is a powerful outlet for creativity, enabling you to surround yourself with beauty. It can provide homegrown food for your family, keep you in touch with nature and is also an invaluable form of exercise. In short, gardening is beneficial to both body and soul. {#blank#}1{#/blank#}.

It all starts with good soil.

Whatever you're growing, fertile soil is the key. {#blank#}2{#/blank#}. It promotes root development, supplying nutrients for plant growth.

Grow vegetables that keep on giving.

{#blank#}3{#/blank#}, choose ones you can harvest more than once. Lettuce and basil are quick and easy to grow. They'll replace their leaves every time you cut them. Vegetables like these mean continuous harvests, which is huge for keeping spirits high.

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Some plants will grow tall and some will grow closer to the ground. Tall plants will shade shorter plants and prevent them getting needed sunshine. Also, give little seedlings plenty of room to stretch and grow. If they grow too close together, don't be afraid to thin seedlings.

Save money with seeds and cuttings.

Buying all of your plants from the garden center is expensive. {#blank#}5{#/blank#}. Reach out to friends and family who garden and ask them to share spare seeds with you. Also check to see if they have any plants you can take cuttings from. It takes longer than buying young plants, but it is definitely more satisfying and you will learn so much.