Vacation is a time for refreshment. In work, we are often called to think. Sometimes, it's good to give our brains a rest. Without a break, we may not be able to perform up to our potential. This can be a problem, not only for the employee, but for the employer as well.

    “The main benefit of vacation is for the worker to come back energized,” says Weaver. “If they haven't had a break, then they're not coming back with new energy. They haven't had a chance to step back and get perspective (远景), and come back with renewed enthusiasm.”

    Long working hours without a break, insecurity (不安) about one's job, and other work-related worries can lead to burnout and stress. Humans can usually adapt to pressure, but not for a limitless amount of time.

    “It is a problem of relating good workers and having them loyal to the firm while they're there,” says David Maume, PhD, professor of sociology at the University of Cincinnati. He says burnout can also affect employees' productivity, creativity, and effectiveness.

    In addition, high levels of stress are likely to be precursors (前兆) to depression, which can hit both the employer and employee's pocketbook. Even people who manage to remain productive at work can have problems. If they're always at work, then they're not with their family and friends. If they're working while on vacation, for the time that they're on the job, they're not really present.

    An unbalanced emphasis on work can strain family and social life. When you come up for air, you may see that you're alone, or that your relationships have gone on without you.

    Babies made from three people approved in UK

Babies made from two women and one man have been approved by the UK's fertility regulator. The historic and controversial move is to prevent children being born with deadly genetic diseases.

    Doctors in Newcastle - who developed the advanced form of In Vitro Fertilization or IVF (人工授精) - are expected to be the first to offer the procedure and have already appealed for donor eggs. The first such child could be born, at the earliest, by the end of 2017.

    Some families have lost multiple children to incurable mitochondrial (线粒体的) diseases, which can leave people with insufficient energy to keep their heart beating.

The diseases are passed down from only the mother so a technique using a donor egg as well as the mother's egg and father's sperm has been developed.

    The resulting child has a tiny amount of their DNA from the donor, but the procedure is legal and reviews say it is ethical (伦理的) and scientifically ready.

    "It is a decision of historic importance," said Sally Cheshire, chairwoman of the Human Fertilisation and Embryology Authority (HFEA)."I'm sure patients will be really pleased by what we've decided today."

    But some scientists have questioned the ethics of the technique, saying it could open the door to genetically-modified(转基因) 'designer' babies.

    The HFEA must approve every clinic and every patient before the procedure can take place. Three-person babies have been allowed only in cases where the risk of a child developing mitochondrial disease is very high.

    Prof Mary Herbert, from the Newcastle Fertility Centre, said: "It is enormously pleasing that our many years of research in this area can finally be applied to help families affected by these devastating diseases.

    "Now that that we are moving forward towards clinical treatments, we will also need donors to donate eggs for use in treatment to prevent affected women transmitting disease to their children."

    Prof Sir Doug Turnbull, the director of the Wellcome Centre for Mitochondrial Research at Newcastle University, said: "We are delighted by today's decision. We will also provide long-term follow up of any children born."

    NHS England has agreed to fund the treatment costs of the first trial of three-person IVF for those women who meet the HFEA criteria, as long as they agree to long-term follow up of their children after they are born.

    The Children's Groundwater Festival, first organized by the Groundwater Foundation 19 years ago, is celebrated every year in Nebraska, a state of the central United States in the Great Plains. After organizing the festival for 16 years, the foundation passed the program on to the local community of Grand Island, Nebraska. The festival is an annual event for fourth and fifth graders of Nebraska. It is an interesting and energetic day filled with hands­on education. Water magic, folk singers and musicians, storytellers, and bird shows add to the happy atmosphere during the festival. There are also some educational activities:

    Gooey Garbage: Children build a landfill (废物填埋场) and learn how a properly­built landfill can protect groundwater.

    Water Races: Children learn about water pollution by racing a drop of water through a model.

    Well in a Cup: By building a small aquifer (蓄水层) in a cup, children learn about aquifers and drinking water wells.

    Taster's Choice: Children drink different types of water, from tap water to bottled water. Then they are taught about the treatment process of each type of water.

    There's No New Water: Students are taught to make a special glass container and learn about the water cycle.

    The Children's Groundwater Festival not only has a great influence on Nebraska's people. So far, similar festivals have been held in nearly 40 American states, Mexico City, several provinces in Canada, and New Delhi, India. People everywhere are realizing the importance of educating young people to learn and care about groundwater.

    For more information about this festival, remember to watch our program tomorrow evening. I'll be waiting for you.

    Scientists dug up human remains from the Stonehenge dating back to about 5,000 years ago. To our surprise, people journeyed far to get to the Wessex site. These men and women potentially played a huge role in the construction of Stonehenge.

    The study, published in the journal Scientific Reports, reveals that a number of people buried at the Wessex monument originated from West Wales, which is also the source of the bluestones used in Stonehenge's early construction.

    According to a report from the University College London, scientists from Oxford and Belgium came together to analyze 25 of the burials dug in 2008. Many of them were buried around 3,000 BC, which is around the time when the bluestones were put up to form the Aubrey holes around Stonehenge. The famous stones weren't built until 500 years later. The team used chemical isotope (同位素) analysis and radiocarbon dating (放射性碳年代测定法) the study and found out that at least 10 of the 25 individuals analyzed didn't live near the Stonehenge site but in western Britain. This region includes West Wales, where the bluestones were sourced. Furthermore, the wood that was used to burn the bodies was also found to have come from different trees. Some of the pieces of trees come from trees in dense woodland, many of which are found in West Wales. Some of the individuals may have been cremated elsewhere before being buried in Stonehenge.

    The researchers suggest that these prehistoric people may have been part of the sacred site's early construction crew. They may have been the ones to transport the bluestone materials from the Preseli Mountains in West Wales. The findings are an interesting revelation, particularly since it means that there were significant interregional connections that existed as far back as 5,000 years ago. Even back then, in the Neolithic Period (新石器时代), human civilization had wide contacts and exchanges.

    2.26-meter-tall Yao Ming made his NBA debut (初次登台) on October 23, 2002 and got 6 points for the Houston Rockets in the game. The next day, he got 13 points in another game.

    Most people think that Yao Ming is a born basketball player. But Yao said, "When you watch it on TV, it looks very easy. But when you are playing in the NBA, it is really not so easy." He said that joining the Houston Rockets was a new start and a new challenge. "I hope that through very hard work I can make everyone happy and help the Rockets win more games," he said. Yao Ming speaks some English. Both he and his teammates can understand each other. They don't think there is a language problem. While Yao Ming faces this new challenge, the people of Houston have shown great interest in him and they hope Yao Ming will bring new energy to the Rockets. The team has started having lessons to learn more about China, and many people who work for the Rockets have learned to speak some Chinese.

    Positive thinking is a significant element of happiness. In order to become a positive thinker, determination and consistency are important. The first thing to know about positive thinking is that everyone can do it.  With certain cognitive (认知的) and behavioral changes, we can all become positive thinkers. Another important factor is that being a positive thinker does not mean you become numb to anything that is not working properly in your life or is negative - it just means that you approach life and face challenges with a healthier outlook.

    Instead of selectively attending to negative events, focus on the positive ones. Then pay attention to the delayed consequences of your behavior rather than the immediate ones. For example, if a job is not going like you want, focus on the fact that you have a job and how you can take your time to make the situation better.

    Challenge any internal attributions and see if you compare your behavior to standards that are excessively rigid and perfectionistic. If so, change these and be reasonable with your comparisons. For example, if you constantly compare your weaknesses with other people's strengths, then switch this and compare yourself with those who are doing poorer than you as well. Overall, people who focus more on their strengths than their weaknesses but at the same time are aware of their weaknesses have a healthier self-evaluation result.

    When faced with too much fear about a situation, imagine the worst case and visualize a solution for it, then let go of fear. This way, you will be prepared for anything and your fear will not block you from being open and creative to different solutions. For example, if you are constantly worried about losing your job up to a point where it is creating a lot of anxiety and fear and is effecting your performance and your happiness negatively, then think of losing your job, visualize how you will handle it, find solutions in your mind and then let go of the thought and the fear attached to it.

    So positive thinkers are better problem solvers and have better interactions. In addition to that, people who are positive thinkers are happier and more satisfied with their life.