Think about vitamin D when you're catching up on summer rays. It's sometimes called the “sunshine vitamin” because it's produced in your skin in response to sunlight. Vitamin D is a fat-soluble (脂溶性的) vitamin in a family of compounds that includes vitamins D-1, D-2, and D-3. It can affect as many as 2,000 genes in the body.

    Vitamin D has several important functions. Perhaps the most vital are regulating the absorption of calcium and phosphorous（磷）, and promoting normal immune system function. Getting enough vitamin D is important for normal growth and development of bones and teeth, as well as improving resistance against certain diseases.

    In addition to its primary benefits, research suggests that vitamin D may also play a role in: reducing your risk of multiple sclerosis（多发性硬化）, according to a 2006 study published in the Journal of the American Medical Association decreasing your chance of developing heart disease, according to 2008 findings published in Circulation helping to reduce your possibility of developing the flu, according to 2010 research published in the American Journal of Clinical Nutrition regulating mood and warding off depression losing weight or preventing heart disease.

    How do you get it? Your body produces vitamin D naturally when it is directly exposed to sunlight. A little can go a long way. All you need is 10 minutes a day of midday, pre-sunscreen sun exposure,especially if you have fair skin. Besides getting vitamin D through sunlight, you can also get it through certain foods and supplements to ensure adequate levels of the vitamin in your blood.

    First Lady Michelle Obama is on a five-day trip to Asia. She is visiting Japan and Cambodia to help publicize a program called "Let Girls Learn". Administration officials set up the campaign to support the education of millions of girls worldwide.

    Before her trip, Mrs. Obama and her husband noted the inability of an estimated 62-million girls to attend school. They said educating the girls should be a foreign policy goal.

    This week, Mrs. Obama criticized the fact that tens of millions of girls are not receiving a satisfactory education. In her opinion piece, she wrote this failure to educate girls it was more than "a tragic waste of potential." It is both a serious public health issue and a problem for the economic health of nations and the world. She also said it was "a threat to the security of countries around the world".

    The First Lady noted by 2012, every part of the developing world was educating both girls and boys in primary schools. But this is not the case in secondary education. She wrote in some areas girls face "the cultural values and practices that limit the prospects of women in their societies ".

    The Obama administration launched the "Let Girls Learn" campaign earlier this month. At the time, Mrs. Obama noted plans to involve the U.S. Peace Corps, and the Volunteer Development Agency.

    "This effort will draw on the talent and energy of the nearly 7,000 Peace Corps volunteers serving in more than 60 countries. Through this effort, Peace Corps will be supporting hundreds of new community projects to help girls go to school and stay in school. And, I want to emphasize that these programs will be community-generated and community-led. They will be based on solutions devised by local leaders, families and yes, even the girls themselves."

    President Obama also spoke at the same White House event, saying that campaign is important to his administration.

Yellowstone Weather

    Yellowstone National Park is at lofty height. Height. Most of the park is above2,275meters.

    Yellowstone's weather is unpredictable. In summer, it may be warm and sunny with temperatures in the high 70s. At night in any given month, the temperature may drop close to freezing. So it is best to come prepared for cold evenings and mornings,especially if you are camping or hiking. When you leave your campsite,please leave it prepared for possible thundershower and wind.

A sunny warm day may become fiercely stormy with wind, rain, sleet and sometimes snow. Without enough clothing, an easy day hike or boat trip can turn into a battle for survival.

    Norman Garmezy, a development psychologist at the University of Minnesota, met thousands of children in his four decades of research. A nine-year-old boy in particular stuck with him. He has an alcoholic mother and an absent father. But each day he would walk in to school with a smile on his face. He wanted to make sure that "no one would feel pity for him and no one would know his mother's incompetence.” The boy exhibited a quality Garmezy identified as “resilience”.

    Resilience presents a challenge for psychologists. People who are lucky enough to never experience any sort of adversity (逆境) won't know how resilient they are. It's only when they're faced with obstacles, stress, and other environmental threats that resilience, or the lack of it, comes out. Some give in and some conquer.

    Garmezy's work opened the door to the study of the elements that could enable an individual's success despite the challenges they faced. His research indicated that some elements had to do with luck, but quite large set of elements was psychological, and had to do with how the children responded to the environment. The resilient children had what psychologists call an “internal lens of control(内控点)”. They believed that they, and not their circumstances, affected their achievements. The resilient children saw themselves as the arrangers of their own fates.

    Ceorge Bonanno has been studying resilience for years at Columbia University's Teachers College. He found that some people are far better than others at dealing with adversity. This difference might come from perception(认知) whether they think of an event as traumatic(创伤), or as an opportunity to learn and grow. “Stressful” or “traumatic” events themselves don't have much predictive power when it comes to life outcomes. "Exposure to potentially traumatic events does not predict later functioning,” Bonanno said. "It's only predictive if there's a negative response.” In other words, living through adversity doesn't guarantee that you'll suffer going forward.

The good news is that positive perception can be taught. "We can make ourselves more or less easily hurt by how we think about things," Bonanno said. In research at Columbia, the neuroscientist Kevin Ochsner has shown that teaching people to think of adversity in different ways--to reframe it in positive terms when the initial response is negative, or in a less emotional way when the initial response is emotionally “hot”—changes how they experience and react to the adversity.

    Philadelphia offers a ton of attractions that are suitable for people of every age and here are some family—friendly attractions.

    Spruce Street Harbor Park

    Spruce Street Harbor Park, one of the best urban beaches in America, is an outdoor heaven on the Delaware River waterfront. Visitors can relax in a hammock, play on the playgrounds, and play games like table tennis and giant chess. Don't miss out on the park at night, when colorful LED lights hanging from treetops make the entire area bright.

    Blue Cross River Rink

    Offering ice skating in the winter and roller skating in the summer, Blue Cross River Rink creates a fun, outdoor experience for the whole family. Visitors can play on the nine-hole mini-golf course during the summer, and enjoy eats and drinks from the on-site bar and restaurant all year round.

    Sesame Place

    Big Bird, Elmo and the other stars of Sesame Street come out and play at Sesame Place, the only theme park in the nation starring the popular TV show's most lovable characters. A water park, interactive activities, parades, fireworks and shows add to the fun.

    Once Upon a Nation Storytelling Benches

    On summer days, uniformed and professional storytellers at 13 storytelling benches throughout Philadelphia's Historic District entertain visitors with true, free, three-to-five minute tales about the colonial era as part of Once Upon a Nation. Children can pick up a Story Flag at any storytelling bench, and then collect a star from every storyteller on their journeys. Flags with all the stars can get free rides on the Parx Liberty Carousel at Franklin Square.

You see a fantastic offer, like a hotel room. You decide to book. Then it turns out there is a service fee. Then a cleaning fee. Then a few other extra costs. By the time you pay the final price, it is no longer the fantastic offer you thought.

Welcome to the world of drip pricing — the practice of promoting something at an attractive headline price and then, once you've committed to the purchase process, hitting you with unavoidable add-ons that are"dripped".

In most cases, you see through all additionally added mandatory fees, and even though you could relinquish the deal, you choose to bite the bullet and complete the deal. Resistance to the idea of starting the search all over again is not simply a matter of laziness or indecision. There's a profound psychological mechanism at play here, called the present bias.

In the paper, Doing It Now or Later, economist Matthew Rabin defines people' s present-biased preference via an example of choosing between doing seven hours of unpleasant activity on April 1 or eight hours two weeks later: If asked on February 1, most people will choose the earlier option. But come April 1, given the same choice. most of us tend to put off work till April 15. In simple terms, the inconvenience of doing something"right now" often feels disproportionately large. Beyond the challenge of starting over, there's another psychological phenomenon that drip pricing uses - loss aversion. Imagine you're booking tickets for a show. Initially attracted by the headline price, you're now presented with different seating categories. Seeing a VIP ticket is within your budget, you decide to fork out. But then, during the checkout process, the drip begins. You realize you could have chosen lower-category seats, but by this stage, you've already imagined yourself enjoying the show from those nice seats. Going back to a cheaper seat will feel like a loss.

Buyers would benefit from a ban on drip pricing. Many countries are taking steps to protect consumers from drip pricing. The effectiveness of such measures, however, is uncertain. Nonetheless, you can hopefully make a more informed decision by understanding why the strategy works.