For the Travel section, writers and editors selected special items to profile from a dozen cities.

Brussels:Chocolate

    Nearly half the chocolate consumed in the world is eaten in Europe, and Belgium—with average consumption of 14.99 pounds per person a year—certainly covers its fair share. While Brussels, the country's capital, is home to hundreds of chocolate makers, what makes a visit necessary is the rich heritage of traditional chocolate makers.

Budapest: Paprika (红辣椒)

    The job of preparing Hungarian paprika was once considered too dangerous for mothers to do. A woman who touched her children upon returning from work risked burning them, so only the elderly and unmarried were allowed the delicate task of separating the skin from the flesh. But by the early 20^th century, sweeter varieties and a machine turned paprika into a common feature of all Hungarian cuisine.

Lisbon: Tiles (瓷砖)

    Is there a bluer Country than Portugal? The blue sky and Atlantic Ocean embrace the land. The blue moods of Fado, the dark folk music, form the national soundtrack. And all across Portugal, the typically blue designs of azulejos—ceramic tiles—are spread across churches, castles, palaces, university halls, parks... The result is a beautiful land of Christian saints, Portuguese kings, historical glories, aristocrats at leisure, seascapes and so on.

Madrid: Guitars

    Walking into one of Madrid's storied guitar makers' workshops can feel like stepping into the past. Curly wood shavings, from the palest pine to ebony, fall onto the floor as artisans turn some humble wood into works of art. It's painstaking work—all done by hand—with classical guitar models and the methods of making them changing little over the last century.

    The four theme parks below offer the most thrilling(刺激的)rides and attractions in the world.

Busch Gardens Williamsburg

    Located(坐落)in Virginia, USA, this theme paprk has some of the highest-rated thrill rides in the world. The park's famous roller coasters include Apollo's Chariot, Alpengeist, Griffon, the Loch Ness Monster and Verbolten. The park also has thrilling water rides, rides for kids, other rides, shows, tours, animal exhibits and more. Divided into nine areas representing European countries, the park has won an award for the quality of its food.

Everland

    One of the world's most popular theme parks, Everland is located in Yongin, Gyeonggi-do province, South Korea. The park has 40 thrill rides, including a world-famous wooden roller coaster, and many other attractions such as an hunting ride, a zoo, indoor and outdoor water parks, shows and more.

Blackpool Pleasure Beach

    This Lancashire amusement park is one of the most visited theme parks in the United Kingdom. Among the park's 125 rides and attractions are the tallest and faster roller coaster in the U. K., a classic wooden roller coaster, a steel tower ride, the biggest indoor dark ride in the world, a host of rides for kids and more.

PortAventura World

    Located on Spain's Costa Daurada, this park is divided into six themed areas. Five areas represent different locations including Polynesia, Mexico, the American West, China and the Mediterrancan. The sixth and newest area has a Sesame Street theme. The park has many rides and attractions suitable for visitors of all ages.

Dogs are man's best friends—they are very good for children's health. Researchers found that family pets helped to protect babies against breathing problems and infections (感染).

    A team from Kuopio University Hospital in Finland studied 397 babies born at their hospital between September 2012 and May 2015 for their first year. They found that babies who lived with a dog or a cat spent fewer weeks with ear infections, coughs or runny noses. They were also less likely to need antibiotics (抗生素) than babies in homes without a pet.

    Study author, Dr. Eija Bergroth, said dogs brought dirt and bacteria (细菌) into the home, which helped children's immune system (免疫系统) to be strong. This improved their defenses against bacteria.

    As part of the study, parents filled out weekly diaries starting when the children were nine weeks old, recording information on babies' health as well as their contact with cats and dogs. They recorded if they had fever, ear infections, coughs or running noses. They also put down whether they needed antibiotics.

    Based on those diaries, the researchers found that about a third of the children spent most of their first year with a pet dog and 24 percent in a home with a cat. And children with no dog contact at home were healthy for 65 percent of the time, compared to between 72 and 76 percent for those who did have a pet.

    The researchers also found that contact with dogs, more than cats, was tied to fewer weeks of sickness for babies.

    However, the researchers said they couldn't rule out the possibility that people who own dogs are less likely to get sick for another reason, not due to any protection offered by pets.

    The smallest kids on Earth are much smaller than you or your baby brother or sister. They're even smaller than the hairs on your head. We call them “NanoPutians”(纳米小人). Also known as NanoKids, the NanoPutians aren't real people. They are actually tiny molecules (分子) made to look a little bit like people.

    James Tour invented the NanoPutians as a way to teach kids about nanoscience, which refers to the study of things that are smaller than about 100 or 200 nanometers. “The exact size is less important than the possible applications of working with such tiny things,” Tour says, “Nanoscience is the study and development of the small so that it will affect the large.”

One of the goals of the research is to control individual atoms. Carbon, hydrogen, oxygen, and other types of atoms are the building blocks of the universe. They make up planets, rocks, people, trees, CDs — all the stuff out there. “Most things that people build come together in a top-down way”, Tour says. If you want to make a table, for instance, you cut down a big tree, make wooden boards, and hammer them together. Nature, on the other hand, builds things from the bottom up. When atoms join together they make molecules. Each molecule has a certain shape, and a molecule's structure determines what it can do. Molecules can make them come together to make a cell — or a tree.

    Tour and his co-workers turned these molecular structures into cartoon figures and made an animated(动画的) science video about the little people, set it to music and started showing it to kids in school while talking about how exciting research on small things can be.

    “Learning about the NanoKids has opened up a world of possibility for real kids who ordinarily would rather not study biology, chemistry or physics.” Tour says. When you look closely enough, the really small can be really cool.

    A recent experiment proves that bees can save time and energy when they fly around to different flowers.

    Dr Nigel Raine, from the Royal Holloway University of London, has always been interested in finding out why animal behave like they do. He is also interested in bees. It was not a surprise when he and some other scientists from Queen Mary University of London discovered that bees can quickly solve a problem that takes computers many days.

    Flowers make pollen (花粉), and when bees visit them, they carry the pollen to other flowers. The plants need the pollen to make seeds that will grow. Dr Raine notes that we get a lot of our food from plants, so it is important to know how the bees move around and take the pollen between flowers. The scientists wanted to examine the journey that the bees take and how they save energy when they do this. They completed the experiment on the roof of Queen Mary University, using artificial flowers and a large amount of nectar, a sweet liquid produced by flowers. They taught one bee to visit all the flowers in one place at the same time. When the bee got to know the location of the flowers well, they saw how it flew around and returned home with the nectar. After this, they changed the locations of the flowers. The scientists thought the bee would follow the route it knew already. This would mean that it followed a longer route than it needed to, and so it would use more energy. They watched the bee carefully as it travelled between the flowers in their new location, and they made notes. But in the experiment, the bee changed its route and flew a shorter distance.

    The problem that the bee solved is similar to a maths puzzle called the 'travelling salesman problem'. A salesman who goes to different places to sell things wants to travel the shortest distance. But he has to calculate the length of many possible routes to know which one is the shortest. A computer can calculate this but the experiment shows bees can do the same calculation quickly with a tiny brain. Scientists are very interested in how they do this. It would help us to understand how pollen is moved around. In addition, if they find this out, it could help us to improve communication networks. This might help humans to reduce traffic jams when there is an accident, for example.

    Language learning apps are very popular now and offer opportunities to learn vocabulary and practice grammar. But there has been a discussion about just how effective such apps can be.

    Among the most popular apps are Duolingo and Busuu. A previous research found positive results on the use of them. But it mainly concentrated on studies with learners who had signed up to language courses and these apps worked as an after-class support, so the results were not always reliable. A recent study of 4,095 Busuu users has been carried out aimed to find out if users can actually learn a language with an app.

    Busuu provides learning materials for 12 different languages. It offers special model where some content is available for free while some content is not. We find that its users are an even mix of men and women. More than half consider themselves to be at the beginner level as there is a decrease in users as their language levels go up. Most people use the app because of personal interest, or because they want to study or live abroad. Female users tend to use it less often but for longer periods of time than male users.

    Getting any feedback on Busuu depends on whether your answer is correct or not. While it is helpful, this is not the sort of feedback language teachers prefer, as it does not explain why the answer is right or wrong. In spite of this, feedback in the app is very highly rated.

    More than 92% of respondents state that the app has met their expectations and 86% rate the app as very good or good. In fact, more than 80% of the users surveyed strongly agree that using the app has helped them improve their knowledge of the language they are learning.

    Besides, language learning apps also create an environment where mistakes are only known to the users, and this can address the performance anxiety that many learners suffer from when asked to speak a foreign language. So language teachers should encourage their students to use them to do the grammar work, leaving precious class time for more language communication.