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!

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    China is a land of bicycles.At least it was back in 1992 when I traveled the country.Back then everyone seemed to be riding a bicycle.Cars were fare.Yet since my arrival in Beijing last year,I've found there are millions of cars. However,bicycles are still popular nowadays.People still use their bicycles to get around.For many,it's the most convenient and cheapest way to travel today.

    It's rush quickly through crossroads,move skillfully through traffic,and ride even on sidewalks（人行道）. Bicycles allow people the freedom to move about,which cars just can't provide.Eager to be part of this aspect of Chinese culture,I decided to buy a bicycle.Immediately I got my new bike I jumped up on the seat and started home.

    My first ride home was orderly（守秩序的）.To be safe, I stayed with a "pack" of bikers while cars on the streets came running swiftly out of nowhere at times.I didn't want to get hit.So I took the ride carefully.Crossing the streets was the biggest problem.It was a lot like crossing a major highway back in the United States.The streets here were wide,so crossing took time,skill and a little bit of luck.

    I finally made it home.The feeling on the bicycle was amazing.The air hitting my face and going through my hair was wonderful.I was sitting on top of the world as I passed by places and people.Biking made me feel alive.

    Starting Cycling

    We have two services designed to give people the confidence and knowledge to cycle successfully.

    Lessons

    All our instructors have been trained to National Standards level of “Bike-ability”. This means you will be trained to a standard consistent across the whole country.

    There are 3 levels of skills to progress through. Children would start with levels 1 & 2, progressing from the playground or park to cycle on less busy local roads. Teenager and adult beginners can also learn levels 1 & 2 in an off-road and quiet environment.

    Confident teenagers and adults can broaden their skills by learning level 3, using multi-lane roads and larger roundabouts. We provide both a complete package of lessons for the beginner or individual lessons tailored to the client. Whatever the need we can address and practice until perfect!

    Cost is ￡30 per hour.

    Guided Ride

    We know that riding on the roads in London can be scary, and if you have to navigate (确定行车路线) as well it can become a real hard task! The Guided Ride service takes all the stress out of it for you by providing the following:

    Route planned in advance to suit your skill level. Route map provided to you.

    Cycle and equipment checked. We will teach you a simple method to check basic roadworthiness (车辆性能) of your bike that you can perform on a weekly basis.

    Route discussed and focus given to any areas requiring special attention.

Cycle along with the instructor close behind. Here the traffic can be controlled by the instructor and rider observed.

    We currently cover London Zones 1 & 2. Please contact us if your requirements are outside of these areas.

    Cost ￡30 per hour.

    There is an English saying that says, "Let Sleeping Dogs Lie." It means not bringing up an old problem. Researchers in Hungary have found another reason to let dogs keep on sleeping. It seems the animals are learning while they sleep.

    The Hungarian researchers placed tools on the dogs' heads to know about electrical activity in the brain. The brain activity, called sleep spindles(梭状波), takes place in human begins, and has been connected with learning. The researchers hope to understand how the dogs' ability to learn and remember changes as they get older. The study may help them understand how human brains change as we age.

    The researchers found differences between male and female dogs. Iotchey, a researcher, says the females appeared much better at learning new things. Female dogs have about twice as many spindles per minute as male dogs, they also happen to be the better learners, and they memorize the task much better. But it was harder for all the older dogs to remember things, especially when several things were happening at the same time.

    DoraSzabo also studies sleep spindles. Szabo is a neuroscientist in a university in Budapest. She says the older dogs have fewer spindles and are easily cheated. "If you first hide the reward into one bowl, then in another and in another, they get lost after a while. So their performance is going down, and they are getting poor in solving new problems."

    Researchers hope the study will not only help understanding of learning ability and memory changes in dogs, but also the aging of humans. Senior Researcher EnikoKubinyi adds that the aging dogs suffer from the same problems as humans who are aging. “Among very old dogs, up to two thirds of them show signs of dementia(痴呆), and this dementia is really very similar to that of humans, so we could use dog as a natural model of human aging."

Land of fire and ice: Iceland

    Join an unforgettable tour of Iceland's splendid landscapes, timed to arrange four days filled with volcanic and geological adventure, and evening opportunities to see the Aurora Borealis.

    Day 1: Vatnajokull Glacier (冰川)

    Today you'll take a walk on Europe's biggest ice cap-Vatnajokull-which has around 30 glaciers flowing out from it. No experience is necessary to take part in the hike. It's discouraging to think that the glacier is retreating due to rising world temperatures, and in future years the glacier may be gone. If you prefer a relaxing morning you can explore the surroundings of the farm stay and head to the Thorbergur Centre.

    Day 2: Secret lagoon (泻湖) and Reykjavik

    This morning we make our way to the Lava Centre which is an interactive, high-tech educational exhibition describing volcanic activity, earthquakes and the creation of Iceland over millions of years. After our visit, we will continue to the Secret Lagoon natural hot springs, located in the small village called Fludir, giving you the opportunity to relax in the warm waters before travelling to Reykjavik.

    Day 3: Reykjanes peninsula (半岛)

    Head out to the Reykjanes Peninsula. It is a land-born highly volcanic counterpart of the Mid-Atlantic Spreading Ridge where two tectonic plates part at an average rate of 2.0-2.5 cm/yr. Four volcanic systems and fissure (裂缝) groups line the peninsula from SW to NE. They contain open fissures, normal faults, high-temperature fields and volcanic fissures.

    Day 4: Depart Reykjavik

    Today is departure day and time to say "sjaumst". Your group departure transfer will take you to the airport for your flight home.

Few people enjoyed getting shots at the doctor's office. But many of these shots are important vaccines (疫苗) that help prevent us from getting certain diseases or types of infection.

Vaccines got their start in Europe in the 1720s, when a British woman named Lady Mary Wortley Montagu was visiting Turkey. She saw Turkish doctors purposefully inoculating (接种) people with small amounts of smallpox. Smallpox is a painful, deadly disease that had no cure at the time. But Lady Montagu was amazed that the patients not only recovered, but then proved to be immune (免疫的) to the disease!

Lady Montagu quickly returned to England, excited to share this new procedure. But inoculation took many years to catch on. One problem was that no one had a correct way of inoculating people safely. Occasionally, patients would become fully infected and then begin spreading the disease. However, inoculation eventually saved enough people for it to become the common practice for preventing smallpox.

Some years later, a scientist named Edward Jenner discovered that people who had been infected with a disease called cowpox became resistant to smallpox. Cowpox was less much harmful than smallpox. Jenner convinced doctors to inoculate people with cowpox, which led to a very safe vaccine and far fewer outbreaks of smallpox. Finally, a French scientist named Louis Pasteur realized that Jenner's idea could be used to treat other diseases. Since then, vaccines have been made for many other diseases, such as polio, tetanus, and rabies.

Today, scientists and doctors continue to create new vaccines that could potentially save millions of lives worldwide.