Weddings in the United States vary as much as the people do. There are church weddings with a great deal of fanfare(仪式上的短曲); there are weddings on mountain tops with guests barefooted; there have been weddings on the ocean floor with oxygen tanks for the guests. But many weddings, no matter where or how they are performed, include certain traditional customs.

    Before a couple is married, they become engaged. And then invitations are sent to those who live nearby, their close friends and their relatives who live far away. When everything is ready, then comes the most exciting moment.

    The wedding itself usually lasts between 30 and 40 minutes. The wedding party enters the church while the wedding march is played. The bride carrying a bouquet enters last with her father who will “give her away”. The groom enters the church from a side door. When the wedding party is gathered by the altar, the bride and groom exchange vows(誓言). It is traditional to use the words “to have and to hold from this day forward, for better, for worse, for richer, for poorer, in sickness and in health, to love and to cherish, till death do us part.” Following the vows, the couple exchange rings. Wearing the wedding rings on the fourth finger of the left hand is an old custom.

    After the ceremony, there is often a party, called a “reception” which gives the wedding guests an opportunity to congratulate the new couple.

    The car in which the couple leaves the church is decorated with balloons. The words “Just Married” are painted on the trunk or back window. And then the couple go in their honeymoon.

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    The pupils of Grangetown High have been busy getting to know their newest and tallest classmate — a 7-meter-tall giraffe outside their school.

    The giraffe is a huge sculpture (雕像). The school's headmaster noticed it in an artist's garden as he drove past one day, and thought it would be perfect for his school. “I knew everyone would love it,” he said, “because our basketball team is known as the Grangetown Giraffes, and they wear giraffes on their shirts. So I asked them to write to the artist, asking how much it would cost to buy the giraffe. He was very kind and got it ready to deliver (递送) in six weeks — all for nothing! It was expected to arrive one Sunday morning, so that the pupils would see it when they got to school on Monday — at that time they had no idea that we were getting it.”

    The artist, Tom Bennett 9 was a university professor of chemistry before he retired in 2012 and only took up metalwork a couple of years ago. “I've always drawn pictures,” he said. 441 can even remember doing it on my first day at school — I drew a horse. I wanted it to be the best horse picture ever, but I don't think I succeeded.” Tom's first metalwork was a bicycle on which he and his wife could go cycling together, “It was the most uncomfortable bike ever created,” he said, “so I gave up making bicycles and went into sculpture instead.”

    Meanwhile the pupils at Grangetown High are very happy with their new classmate. “We're going to hold a competition to give it a proper name,” said one girl. “Everyone likes the expression on its face, so perhaps that will give us some ideas.”

    Wood has many great characteristics that make it the perfect building material. It is cheap, durable, easily available, and most importantly, environmentally sustainable. The one thing it is not, is transparent! Now thanks to a team of scientists at Stockholm's KTH Royal Institute of Technology the material may even be able to add that feature to its already impressive list.

    Lead researcher Dr, Lars Berglund said he was inspired to create the transparent wood after learning how Japanese researchers had developed a see-through paper for use in flexible display screens for electronic devices. The team began by pulling out the wood's lignin(木质素). The lignin-free wood was then dipped into a polymer(聚合物)and baked at a temperature of 158°F for four hours. The result was a hybrid product that was not only stronger and lighter than the original wood but also, almost transparent. The researchers were able to adjust the level of transparency by varying the amount of the polymer injected and also by changing the thickness of the wood.

    While scientists have previously created a see-through wood for small-scale applications like computer chips, the transparent wood is the first one being considered for large scale applications. The researchers, who revealed their findings in Biomacromolecules on April 11, picture using the transparent wood in buildings to allow for more natural light, or to create windows that let in the desired amount of light without sacrificing privacy.

    Wood that allows light to pass through could lead to a brighter future for homes and buildings. Berglund also thinks the wood could play a significant role in the design of solar panels. The semitransparent material would be able to keep light longer and give it more time to interact with the conductor, thus resulting in better solar efficiency. Additionally, substituting the currently used glass with this new product would help solar energy manufacturers improve their carbon footprint and lower the cost. They are now experimenting with ways to scale up the manufacturing process so that the transparent material is cost-effective to make and easy to use.

    New study shows that when teachers participate in a training program focused on prosocial (亲社会的) classroom behavior, their students are better able to control their emotions, and that children who can regulate emotions are more likely to be academically successful.

    For the study, which appears in Prevention Science, researchers looked at more than 100 teachers and 1,817 students from kindergarten to third grade to see if teachers could support students' emotional and behavioral growth through the Incredible Years Teacher Classroom Management (IYTCM) program.

    The program uses videos and training sessions, along with role-playing and coaching, to help teachers learn management skills such as using behavior-specific praise, building positive relationships with students, and considering how to reduce poor behavior. Teachers in the training group increased interactions with students by 64 percent compared with 53 percent for teachers in the control group without the training.

    "Emotional regulation is the ability to recognize what behavior is appropriate in the present situation," says Wendy Reinke, professor in the College of Education at the University of Missouri. "For example, a student might have difficulty controlling the feeling of anger if he or she becomes annoyed with another student. But under this program, the teacher encourages them to move to a different spot in the classroom, effectively teaching them that sometimes stepping away and taking a break is a good way to calm down and manage8ha8feeling."

    After one school year of using the program in classrooms, students improved their social ability and ability to regulate their emotions. These improvements resulted in an increase in the tests for students in Incredible Years classrooms vs. students in control classrooms. And this classroom management approach can help reduce the risk for struggling learners early on, which could help prevent more accumulative support needs in a child's future.

    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 concentrates on studies with learners who had signed up for 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 to find out if users can actually learn a language with an app.

    Busuu provides learning materials for 12 different languages. It offers special models where some contents are available for free while some contents are 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. Females 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 the people state that the app has met their expectations and 86% consider 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.

Economically speaking, are we better off than we were ten years ago? Twenty years ago?

In their thirst for evidence on this issue, commentators seized on the recent report by the Census Bureau, which found that average household income rose by 5.2% in 2015. Unfortunately, that conclusion puts too much weight on a useful, but flawed and incomplete, statistic. Among the more significant problems with the Census's measure are that: 1) it excludes taxes, transfers, and compensation like employer-provided health insurance; and 2) it is based on surveys rather than data. Even if precisely measured, income data exclude important determinants of economic wellbeing, such as the hours of work needed to earn that income.

While thinking about the question, we came across a recently published article by Charles Jones and Peter Klenow, which proposes an interesting new measure of economic welfare. While by no means perfect, it is considerably more comprehensive than average income, taking into account not only growth in consumption per person but also changes in working time, life expectancy, and inequality. Moreover, it can be used to assess economic performance both across countries and over time.

The Jones-Klenow method can be illustrated by a cross-country example. Suppose we want to compare the economic welfare of citizens of the U.S. and France in 2005.

In 2005, as the authors observe: real consumption per person in France was only 60% as high as the U.S., making it appear that Americans were economically much better off than the French on average. However, that comparison omits other relevant factors: leisure time, life expectancy, and economic inequality. The French take longer vacations and retire earlier, so typically work fewer hours; they enjoy a higher life expectancy, presumably reflecting advantages with respect to health care, diet, lifestyle, and the like; and income and consumption are somewhat more equally distributed there than in the U.S. Because of these differences, comparing France's consumption with the U.S.'s overstates the gap in economic welfare.

Similar calculations can be used to compare the U.S. and other countries. For example, this calculation puts economic welfare in the United Kingdom at 97 % of U.S. levels, but estimates Mexican well-being at 22%. The Jones-Klenow measure can also assess an economy's performance over time. According to this measure, as of the early-to-mid-2000s, the U.S. had the highest economic welfare of any large country. Since 2007, economic welfare in the U.S. has continued to improve. However, the pace of improvement has slowed markedly.

Methodologically, the lesson from the Jones-Klenow research is that economic welfare is multi-dimensional. Their approach is flexible enough that in principle other important quality-of-life changes could be incorporated—for example, decreases in total emissions of pollutants and declines in crime rates.