During the cold winter days, there are some interesting festivals in the world. Look at the following ones.

Harbin Ice and Snow Festival

Place: China

Time: January 5 to February 5

People build incredible things out of ice and snow, decorating them with lights.

The Carnival of Venice

Place: Italy

Time: between February and March

One of the most beautiful festivals in the world, people wear masks and elaborate costumes to hide differences among classes, and there an, contests for the best costumes.

Holi Festival

Place: India

Time: late February/March, on, the last full moon day and Sikhs, in India, Nepal, and Sri Lanka celebrate the main day of this incredibly fun 16 -day festival by throwing colored powder and water at each other.

Sundance Film Festival

Place: Utah, the US

Time: end of February

The largest independent film festival in the US. Watch both feature films and shorts. You need to buy a ticket.

    Ever wondered whether punishment actually makes people cooperate (合作)? A team of scientists created an experiment to figure it out and the results were pretty unexpected.

    To understand what they found, you have to know why these scientists were studying punishment. They were trying to figure out why people cooperate when it's often so easy to profit at others expense. Why don't friends steal from each other? Why do parents bother to feed their children? If the answer to these questions is obvious to you, congratulations, you are ahead of scientists. They're still trying to figure it out.

    In this experiment, researchers had 225 Chinese students play a game, where if the students cooperated, they'd all get a number of points. But if one defected (变节) and everyone else cooperated, the defector would get a lot of points, and the cooperators would lose out. This game represents a lot of real life situations where you struggle with a decision: work together and do OK, or run off with the rewards, ruining everybody else's day.

    This is actually a pretty ordinary economic experiment. But the researchers added two changes to see if they could mimic(糢拟)the real world better. Change one: some students played many rounds together, so they'd learn who they could trust. Change two: people could punish each other, sacrificing a point or two to destroy another player's score.

    In the end, the researchers found that playing multiple rounds made people cooperate more, which definitely mimics human society. But the whole punishment thing led to a surprise: punishing didn't actually make people cooperate more. In fact, it made them cooperate less.

    So the scientists still don't know why people cooperate, though it looks like it has more to do with groups sticking together than it does with punishment.

    Play allows children to use their creativity while developing their imagination and physical, cognitive（认知的）, and emotional strength. Play is important to healthy brain development. Play allows children to create and explore a world they can master, conquering their fears while practicing adult roles. Undirected play allows children to learn how to work in groups, to share, to negotiate, and to resolve conflicts.

    Ideally, much of play involves adults, but when play is controlled by adults, children acquiesce（顺从）to adult rules and concerns and lose some of the benefits play offers them, particularly in developing creativity, leadership, and group skills. In contrast to passive entertainment, play builds active, healthy bodies. In fact, it has been suggested that encouraging unstructured play may be an exceptional way to increase physical activity levels in children, which is one important strategy in the resolution of the obesity problem.

    Children's development is critically influenced by appropriate, affective relationships with loving and consistent caregivers as they relate to children through play. When parents observe their children in play or join with them in child-driven play, they are given a unique opportunity to see the world from their children's vantage point as the child navigates a world perfectly created just to fit his or her needs. The interactions that occur through play tell children that parents are fully paying attention to them and help to build enduring relationships. Parents who have the opportunity to look at their children's world learn to communicate more effectively with their children aid are given another setting to offer guidance. Less verbal children may be able to express their views, giving their parents an opportunity to gain a fuller understanding of their perspective. Quite simply, play offers parents a wonderful opportunity to engage fully with their children.

    Play is essential to the academic environment. It ensures that the school setting attends to the social and emotional development of children as well as their cognitive development. It has been shown to help children adjust to the school setting and even to strengthen children's learning willingness. Social-emotional learning is best integrated（融合）with academic learning; it is concerning if some of the forces that enhance children's ability to learn are improved at the expense of others. Play and unscheduled time that allow for peer interactions are important components of social-emotional learning.

    Music Festivals

    A new study suggests some language learning can take place during sleep. Researchers from Switzerland's University of Bern say they discovered people were able to learn new language words during deep levels of sleep.

    Much of the earlier research found that memories made when awake were strengthened during sleep. This supported the idea that information learned while awake is replayed and deeply embedded in the sleeping brain.

    The researchers theorized that, if replay during sleep improves the storage of learned information while awake, the processing and storage of new information should also be possible during sleep.

    They carried out experiments on a group of young German­speaking men and women, which centered on periods of deep sleep called "up­states". They identified these slow­wave peaks as the best moments for sleep­learning.

    The researchers observed individuals in a controlled environment during brief periods of sleep. Brain activity was recorded as pairs of words were played for the study subjects. One word in the pair was a real German word. The other was a made­up foreign word. For later identification purposes, the German words chosen were things clearly larger or smaller than a shoebox.

    Each word pair was played four times, with the order of the words changed each time. The word pairs were played at a rhythm that is similar to actual brain activity during deep sleep. The goal was to create a lasting memory link between the false word and the German word that individuals could identify while awake.

    When the subjects woke, they were presented with the false language words­both by sight and sound. They were then asked to guess whether the false word played during sleep represented an object smaller or larger than a shoebox. Results of the study found that a majority of subjects gave more correct answers about the sleep­learned words than would be expected if they had only guessed at random.

    The researchers said they measured increased signals affecting a part of the brain known as the hippocampus. This brain structure is very important for building relational memory during non­sleep periods. The researchers also said memory was best for word pairs presented during slow­wave peaks during sleep.

    The study suggests that memory formation in sleep appears to be caused by the same brain structures that support vocabulary learning while awake. The researchers say more studies are needed to support their findings. However, the experiments do provide new evidence that memories can be formed and vocabulary learning can take place in both conscious and unconscious states.

    As the temperature rises, sweaty humans are making a response that is further worsening the problem of climate change. At present, the world just has 1.6 billion air conditioning units, but these units use a surprising total of ten percent of all global electricity supply. While less than a third of families globally are so equipped, the most AC-addicted countries are Japan (in 91 percent of families), the US (90 percent) and South Korea(86 percent).

    New research by the International Energy Agency (IEA) guesses that the total number of AC units is likely to increase to over 5.6 billion by 2050－equal to ten new units being sold every second for more than 30 years－with sales driven particularly by India, China and Indonesia. This will make the use of air conditioning one of the world's largest demands for energy.

    "Growing electricity demand for air conditioning is one of the most critical blind spots in today's energy debate," argues Faith Birol, executive director of the IEA. "With rising incomes, air conditioner ownership will skyrocket, especially in the developing world. While this will improve daily lives, it is quite necessary that efficiency performance be prioritized."

    Birol and the IEA stress the need for new efficiency standards to ensure that consumers are at least buying units that require significantly less power to function, therefore decreasing the total energy demand. Variations on the traditional "vapor compression" technology, which has formed the basis for AC units for more than a century, may appear really important. A water-based system was recently developed by researchers at the National University of Singapore (NUS), which uses 40 percent less electricity and produces only one by-product: drinkable water.

    "Our cooling system can be tailored for all types of weather conditions, from wet climate in the tropics to dry climate in the deserts," says associate professor Ernest Chua at NUS. "While it can be used for indoor living and commercial spaces, it can also be easily used to provide air conditioning for blocks of buildings in an energy-efficient manner."