When I was young, I had an old neighbor named Dr. Gibbs. He didn't look like any doctor I'd ever known. He never shouted at us for playing in his yard. I remembered him as a neighbor who was nicer than anyone else in the neighborhood. When Dr. Gibbs was happy, he was planting trees. And his life's goal was to make it a forest.

    Dr. Gibbs had some interesting theories about planting. He talked about trees that weren't watered would grow deep roots in search of water. So he never watered his trees. He planted an oak (橡树) and, instead of watering it every morning, he beat it with the rolled-up newspaper. I asked him why he did that, and he said it was to get the tree's attention.

    Dr. Gibbs died a couple of years. Every now and then, I walk by his house and look at the trees that he planted twenty-five years ago. They're very strong now.

    I planted a couple of trees a few years later. I watered them regularly and took good care of them. Whenever a cold wind blows, they shake their leaves and branches.

    The funny thing about those trees of Dr. Gibbs was that difficulty seemed to help them in ways comfort and ease never could.

I'm part of the Roots & Shoots program founded by Dr. Jane Goodall. The program is intended to make and promote positive changes in the world. As Dr. Goodall says, "What you do makes a difference, and you have to decide what kind of difference you want to make."

    In Bulgaria, where I live, homeless dogs are everywhere. Many people here turn a blind eye to them. But I cannot ignore the life of a street dog whenever I see one wandering in the street, looking for something to eat. That's why I'm no longer a food waster. When I see wasted food, I always think of a hungry dog climbing to garbage bins, searching for food that people have thrown there. When eating in a restaurant, I'm not afraid to take leftover food to feed stray cats or dogs.

    A week ago, I saw a homeless dog around the garbage bins. Immediately I knelt down, spoke to her softly and ran my hands over her. I could see that she had had puppies. I couldn't imagine how she could have been able to care for them. Hours earlier, I'd bagged up a plate of leftover fish. As I unwrapped it, she wagged her tail and sniffed at it. She ate all the fish in no time.

    It's sad, isn't it? I can't understand why many of us waste so much and think little of it. These homeless animals have taught me that food is precious. Even when I don't have leftovers with me, I'll take the time to get something from the grocery store to feed them.

I know my power is small, so I hope that next time you see wasted food, do turn it into worthy food. You have the power to save a life!

    In 1972, a social worker named Sanjit "Bunker " Roy founded Barefoot College in Tilonia, Rajasthan. Today the college trains women from villages for six months to build and maintain solar panels and other instruments. Barefoot College also offers education to the younger generation both during the day and at its solar bridge schools that meet by lamp light at night.

    The philosophy of the Barefoot College is largely inspired by the principles of Gandhi, starting with quality beyond social classes, sex or religion. As a matter of fact, women are favorably regarded as an underserved population that is necessary to bringing villages together. Another central principle of the college is self-reliance, teaching students to support and think for themselves.

    After the colleges female students have completed their half a year of training, they return to their villages villages, where they wait for solar panel parts to arrive from the college. Once they have all the pieces they need ,they construct the panels and begin collecting solar energy. For each village, the college also provides solar lamps. Villagers can, in addition, order parts for other solar-powered devices, such as water heaters and cooking stoves. Once assembled(组装）, they and the lamps are powered by the solar panels.

    The effect on the villages is huge. Before the solar panels and lamps arrived, villagers had only candles to light their homes. This prevented adults from doing serious work at night, and it made studying difficult for children as well. As for physicians, they have difficulty treating patients and performing operations at night because they had to rely on flashlights.

    Now there is power for not only the electrical appliances that the college provides but also devices like televisions, radios and computers. For the first time, the villagers can even connect to the world through the Internet.

A Colourful Puzzle

    People often wear clothing with colours that express something about themselves. A happy person might choose to wear a bright yellow shirt. A swimmer might wear a sea-blue dress.

    Animals appear in different colours too, but they don't get to pick what they wear every morning. Scientists have known for a long time about some of the ways animal colouring can be beneficial. They know that some animals' colours attract mates or show who is boss. Other animals' colours blend(融合) in with their environment; thus the animals cannot be seen by their enemies. Still, scientists do not fully understand why blue jays are blue or why rainforest frogs are golden. Now many scientists are working hard to figure out the puzzles of animal colours.

    Part of the answer can be found in an animal's habitat, the place where it lives. It turns out that many animals — especially birds, fish, and reptiles — can see more colours than humans can. These creatures notice colours that stand out in their habitat. For example, forests are mostly green, brown, and yellow. For an animal to be seen by others of its species, it would have to be a different colour than its background. That explains why you can find birds of many shades of blue living in forests.

    Another piece of the puzzle lies in what an animal eats. Birds often eat things that have chemicals in them called “carotenoids”(类葫萝卜素). These chemicals are what make tomatoes red and bell peppers bright orange or yellow. When birds eat these foods, the carotenoids affect the colour of their feathers. For example, a cardinal's bright red feathers will become lighter or darker depending on how many berries it has found to eat.

    Some animals do not have any colour at all — but they are not just white; they are transparent(透明的)! Transparent animals live mostly in the ocean. This amazing wonder of nature came about because the animals needed a way to escape their enemies. They are often slow, defenseless creatures that would have no way of fighting back if larger animals wanted to eat them. Because there are few places to hide in the ocean, these creatures have to hide in plain sight. A good example of this kind of transparent creature is the jellyfish. A jellyfish's body is almost all water, so it is very hard to see it floating in the ocean.

    Animals come in all kinds of colours. Their colours are caused by many different factors, and most animals will remain the same colour for their whole lives. Think how lucky we are to get to change our feathers every day!

    Even for a first-time visitor to China, it is impossible to ignore the popularity of Quick-Response (QR) codes. These square-shaped black-and-white symbols in WeChat or Alipay where QR codes are scanned to add new friends or make payments.

    The QR Code system originated in Japan. The engineer Masahiro Hara felt the limitation of the one-dimension barcode in use and thus developed the QR codes which could carry data horizontally and vertically. QR codes could hold much more information than barcode due to their extra dimension. In addition, QR codes have larger data capacity, smaller print—out size and higher resistance to dirt and damage, which make them widely applied in many other applications.

    Though the technology of QR codes is complicated, we can easily create our own QR codes with the help of QR code generators, many of which are available online for free. Users could enter the data they wish the QR code to display, and the generator turns it into a symbol that can be printed or displayed in electronic form. The process of creating QR codes could be really fun when we customise the design of the codes according to our specific needs. For instance, we can adjust the color, add a logo, and create social options etc. Moreover, dynamic (动态的) QR codes are also available. They are more various than standard QR codes because they allow users to edit data entered previously whereas data in standard QR codes cannot be edited once printed. Plus, don't limit your QR code to one mobile scanner. Anyone can scan your code with any reader. A lower barrier to entry makes success more likely for you and the user.

    Meanwhile, we must also recognize the vulnerability of QR codes. Due to its easy access, criminals can steal simply by replacing the QR codes with their own, routing cash into their own bank accounts. Hence, we should all become more conscious towards virtual money transactions through QR codes and participate in additional security measures.

The Nautilus Expedition(探险) to the Cayman Islands

Hi! I'm Talita and this is my blog! Enjoy!

Day 1: August 15^th

Wow! I can't believe I'm actually here on Nautilus. I'm one of five very lucky students chosen to go on Nautilus's four-day expedition to the Cayman Islands. We had a talk from the expedition leader Dr. Katy Croff Bell about where we're going and what we'll be doing. Oh, and all the safety rules as well, of course!

Day 2: August 16^th

What an amazing day! In the morning, we met Dr. Robert Ballard, who discovered the wreck(残骸) of the Titanic! After lunch, we had a tour around Nautilus. We looked at the labs, and we went up to the bridge—that's where the captain of the ship works. I even got a chance to guide the ship! Later we learned about Hercules. This robot is sent deep into the sea to look for shipwrecks, to study the plants and animals, and to look at the rocks in an area.

Day 3: August 17^th

This morning we appeared on the Nautilus Live website and talked to students around the world about our expedition. It was amazing—I feel like a real famous person now! The afternoon was NOT cool, however. There was a big storm , and we all felt very seasick!

Day 4: August 18^th

This morning was beautiful, and the sea was peaceful. Perfect for a dive. Unfortunately, it was Hercules, not us, who got to go diving. In the afternoon, we arrived at Grand Cayman. Although I'm sad to leave the Nautilus team (especially Hercules), I'm excited to explore the islands and the waters!