Suppose you become a leader in an organization. It's very likely that you'll want to have volunteers to help 

with the organization's activities. To do so, it should help to understand why people undertake volunteer work and

what keeps their interest in the work.

       Let's begin with the question of why people volunteer. Researchers have identified several factors that 

motivate people to get involved. For example, people volunteer to express personal values related to unselfishness, 

to expand their range of experiences, and to strengthen social relationships. If volunteer positions do not meet these 

needs, people may not wish to participate. To select volunteers, you may need to understand the motivations of the 

people you wish to attract.

         People also volunteer because they are required to do so. To increase levels of community service, some 

schools have launched compulsory volunteer programs. Unfortunately, these programs can shift people's wish of

participation from an internal factor (e.g., “I volunteer because it's important to me”) to an external factor (e.g., “I

volunteer because I'm required to do so”). When that happens, people become less likely to volunteer in the future.

People must be sensitive to this possibility when they make volunteer activities a must.

          Once people begin to volunteer, what leads them to remain in their positions over time? To answer this 

question, researchers have conducted follow-up studies in which they track volunteers over time. For instance, one 

study followed 238 volunteers in Florida over a year. One of the most important factors that influenced their 

satisfaction as volunteers was the amount of suffering they experienced in their volunteer positions. Although this

result may not surprise you, it leads to important practical advice. The researchers note that attention should be 

given to “training methods that would prepare volunteers for troublesome situations or provide them with 

strategies for coping with the problem they do experience”.

         Another study of 302 volunteers at hospitals in Chicago focused on individual differences in the degree to 

which people view “volunteer” as an important social role. It was assumed that those people for whom the role of 

volunteer was most part of their personal identity would also be most likely to continue volunteer work. 

Participants indicated the degree to which the social role mattered by responding to statements such as 

“Volunteering in Hospital is an important part of who I am.” Consistent with the researchers' expectations, they

found a positive correlation (正相关) between the strength of role identity and the length of time people continued 

to volunteer. These results, once again, lead to concrete advice: “Once an individual begins volunteering, 

continued efforts might focus on developing a volunteer role identity.... Items like T-shirts that allow volunteers to 

be recognized publicly for their contributions can help strengthen role identity”.

    Both of my parents worked full-time when I was a little girl, so my grandmother would stay at our house during the day. We would watch game shows in the living room. Our favorite was The Price is Right. We would call out our answers along with the contestants.

    When I got older and started going to school, we couldn't watch our game shows regularly. That was okay with me, though, because the one thing I liked better than watching game shows with my grandmother was helping her bake. Watching her in the kitchen was amazing: she never seemed to need the recipes but everything she made tasted delicious.

    At first I would just sit in the kitchen and watch, even though I didn't understand what she was doing. As I got older, she let me help with the easy parts, such as measuring the sugar. The day she let me separate the eggs，I felt like I had found complete pleasure.

    At last, my parents decided that I could take care of myself，and my grandmother stopped coming over every day. The love of baking, however, stayed with me. I started baking by myself, and even if the cookies ended up burnt sometimes, more often they turned out pretty well. I tried out new recipes, and whenever I got to a thorny part, I would call my grandmother for advice. Sometimes I would call her just to talk, too. I felt like I could talk to her about anything.

    My grandmother passed away ten years ago, but I still think of her every day. Last week, I found a recipe book she made for me. It included her recipes for brownies, cookies, and my favorite, lemon pie. As I looked through the pages, I thought I could hear her voice. She was the one who taught me not just about baking, but about life.

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    “A room without books is like a body without a soul,” observed the Roman philosopher, Cicero. It can also be a sign of financial problems to come. New research has uncovered a strong connection between the earning of adults and whether they grew up surrounded by books as children.

    Three economists at the University of Padua—Giorgio Brunello, Guglielmo Weber and Christoph Weiss—studied 6000 men born in nine European countries and concluded that children with access to books could expect to earn more money than those who grew up with few or no books.

    They studied the period from 1920 to 1956, when school reforms saw the minimum school leaving age raised across Europe. They booked at whether, at the age of 10, a child lived in a house with fewer than 10 books, a shelf of books, a bookcase with up to 100 books, two bookcases, or more than two bookcases.

    Over the period studied, the research, published in The Economic Journal, found that an additional year of education increased a man's average lifetime earnings by 9%. Men brought up in houses with less than a shelf of books earned only 5% more as a result of the extra year's education, compared with 21% more for those who had access to a lot of books. And those who had access to books were more likely to move to the better-earning opportunities in cities than those without books. The men's first job was also much more likely to be a white-collar job.

    The economists offer a number of theories for the results. “Perhaps books matter because they encourage children to read more and reading can have positive effects on school performance,” they said.

    The number of books in children's homes can effectively predict their cognitive(认知的) test scores. This may indicate a home that encourages cognitive skills, which are important for economic success in life.

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    The year 2117 will be an eventful one for art. In May of that year in Berlin, the philosopher-artist Jonathon Keats' “century cameras”— cameras with a 100-year-long exposure (曝光)time—will be brought back from hiding places around the city to have their results developed and exhibited. Six months after that, the Future Library in Oslo, Norway, will open its doors for the first time, presenting 100 books printed on the wood of trees planted in the distant past of 2017.

    As Katie Paterson, the creator of the Future Library, puts it: “Future Library is an artwork for future generations.” These projects, more than a century in the making, are part of a new wave of slow art intended to push viewers and Participants to think beyond their own lifetimes. They aim to challenge today's short-term thinking and the brief attention spans of modern consumers, forcing people into considering works more deliberately. In their way, too, they are fighting against modern culture—not just regarding money, but also the way in which artistic worth is measured by attention.

    In a similar fashion, every April on Slow Art Day, visitors are encouraged to stare at five works of art for 10 minutes at a time—a tough task for the average museum visitor, who typically spends less than30seconds on each piece of art.

Like the Future Library, the century cameras are very much a project for cities, since it's in cities that time runs fastest and the pace of life is fastest. “Since I started living in a city, I've somehow been quite disconnected,” Anne Beate Hovind, the Future Library project manager, who described how working on the library drew her back to the Pace of life she knew when she was growing up on a farm in her youth, told The Atlantic magazine.

Muir Woods and Sausalito Half Day Tour

    Wander through an ancient coastal redwood forest and explore the artistic bayside on this half-day tour from San Francisco. Travel across the Golden Gate Bridge to visit Muir Woods, home to some of the oldest and tallest trees on Earth. At the end of your tour choose between getting dropped off at Union Square in San Francisco or taking the ferry back to San Francisco.

    Yosemite National Park and Giant Sequoias Day Trip

    Discover the beauty of the Sierra Nevada on this full-day trip to Yosemite National Park from San Francisco. Travel aboard a comfortable van through historic Gold Rush towns to reach the park, where you'll be amazed by supersized natural wonders. Take a hike among ancient trees, and enjoy several hours to explore the park's wonders on your own.

    Niagara Falls Tour

    Escape from New York City and head north to see both sides of the Canadian border on this guided, 2-day tour to Niagara Falls. Visit Niagara Falls on both the American and Canadian sides and take a ride on the famous Maid of the Mist boat. Then, on the road back to New York City, make a stop to shop at the Crossings Premium Outlets, one of the largest outlet malls in the US.

    Napa and Sonoma Wine Country Tour

    Escape to California's famous wine country on this full-day tour from San Francisco. Taste regional varietals at three different wineries including both big-name and family-run estates (庄园). Learn about the winemaking process during guided tours, and appreciate the regional culture with a stop for lunch.

New research into a long-lived tree has shown some of the tricks that have helped it survive for thousands of years. The ginkgo(银杏树) is a huge, slow-growing tree with fan-shaped leaves, native to China, but planted in parks and gardens across the world. Some of the largest ginkgoes are said to be more than 3, 000 years old.

In order to discover how these and other trees can live for so long, scientists from the US and China studied 34 healthy ginkgoes of different ages. The team studied growth rings in each tree's trunk(树干), as well as cells(细胞) from the bark, leaves and seeds. They found that 600-year-old trees were just as healthy as 2-year-olds.

To learn more, the team then looked in detail at the DNA of nine trees aged between three and 667 years old. DNA is the chemical in the cells of plants and animals that holds instructions that tell any living thing how to grow and develop-including what to do at different times in its life At the beginning of a tree's life, DNA instructs the cells in a seedling to divide quickly so the tree grows rapidly. The cells also make special chemicals to help the young plant survive difficult situations, such as disease. As most trees grow older, their DNA tells their cells to divide more slowly (so growth slows down) and to make fewer chemical defenses(防御).

Ginkgoes, however, do things differently. The team found that although their growth finally slows, both young and old trees make protective chemicals." The secret is keeping a really healthy defense system," said researcher Richard Dixon." As ginkgoes age, they show no sign of weakening their ability to defend themselves from things like disease. "Other trees that live for a long time may have the same ability.

For all their defenses, though, ginkgoes cannot live forever--they finally meet with deadly accidents such as fire, disease and storms. While they last, however, these leafy trees are some of the most beautiful trees in the world.