【推荐1】Lisa Gautier receives nearly a dozen parcels of human hair every day. With her San-Francisco-based non-profit organization Matter of Trust, Gautier turns donated hair into mats used to soak up oil spills on land, and booms(long tubes)used for spills at sea.

A standard way to clean up oil from land is to use mats made from polypropylene(聚丙烯). But polypropylene is a non-biodegradable plastic, and producing it ultimately means more drilling for oil. Hair, by contrast, is an environmentally friendly resource that can soak up around five times its weight in oil, according to Matter of Trust, and it is abundant.

Oil spills can pollute drinking water, endanger public health, harm plants and wildlife, and damage the economy. According to Gautier, the spills that hit the headlines only make up 5% of global oil pollution.

Megan Murray, an environmental biologist at the University of Technology Sydney, develops sustainable technologies to tackle oil spills. Her research indicates that as well as being biodegradable, human hair is often just as effective as polypropylene, and in some circumstances even better. “The hair mats are very beneficial to land spills,” says Murray but adds that when raw oil is spilled on beach sand, it is very difficult to absorb it using any of the materials she has tested. Another advantage of hair is that it costs less than conventional materials and is “globally available as a recycled material,” she says.

However, Murray cautions that hair mats are not a perfect solution, because they are single-use, and can only be dealt with by burning or by burying into soil which then isn’t suitable for growing food. She is now researching methods to extract the oil from a used hair mat, meaning both can be reused.

As the hair mat designs aren’t under patent, other groups have begun producing their own mats and booms. Gautier is pleased to see the movement growing. “Anyone can make a hair mat,” she says. “It creates green jobs, it cleans water, it reduces waste in landfill, and it’s promoting renewable resources.”

At the end of the year, it designs events to help children celebrate Christmas without increasing the amount of waste they create. Hanna Seligmann works for the foundation. “So let’s figure out what is in our bag of trash.” She shows adults and children how to reduce waste during the holiday gift-giving season. “You can sort it as a cardboard item or you can sort it as a plastic item.” “We encourage using things that are already in your house like newspaper, old magazines, using a gift within a gift.” Urging people to recycle is important in the Washington, D.C., area, because Potomac River, one of the most famous rivers in the country lies there.

“Over time we realized that really just doing trash cleanups was the symptom of the problem, not getting to the root cause. And so it was just a little over a decade ago that we started the initiative (倡议) itself.” says Seligman.

The Trash Free Potomac Watershed Initiative is an effort by the Alice Ferguson Foundation to support clean agricultural methods. It includes educational programs teaching children about the kinds of pollution that can enter the watershed.

One activity is called the Trash Timeline Game. It teaches children that the things they throw away do not decompose, at the same rate. For example, paper dissolves in about four weeks. An apple core may take two months to rot. A metal can take up to 100 years.

【推荐1】New data presented this week at the annual Associated Professional Sleep Societies (APSS) suggest that a student's preferred sleeping schedule has a lot to do with his or her grade-point average in school. In one study, researchers at the University of Pittsburg revealed that poor sleep habits among high schoolers led to lower grades, particularly in math.

It's no surprise that poor sleep habits may negatively impact academic performance. And dozens of studies have linked an increase in nightly sleep to better cognition and alertness. The new research, however, goes a step further, quantifying the impact of erratic or inadequate sleep on grades. These findings are more convincing than saying that if you get more sleep, you'll feel better," says Jennifer Cousins, a lead researcher of the study.

The study involved data from 56 adolescents (34 female) between the ages of 14 and 18 years. They were asked to fill out sleep diaries for one week and wear a special activity monitor on their wrists, which recorded when the students were asleep or awake. Overall, teens with poor sleep habits received lower grades than students who stuck with a more regular sleep routine.

Interestingly, Cousins also found that different sleep habits had different effects on the students' school performance：those who woke up more often during the night did worse in math, for example, while those who slept peacefully through the night tended to get better grades in English.

These findings bring up new questions about teasing out（探讨）the details of what is important about sleep that impacts learning," says Cousins. "Does more sleep improve our ability to deal with abstract concepts found in math, or does sleep quality increase creativity? We don't know the answers, and don't want to draw those conclusions yet. But this helps us understand more about how sleep helps the things we do in daily life. "

Authors of the study point out that the results provide overwhelming evidence of the importance of sleep during a period of development that is critical for adolescents and recommend sleep education as a prevention tool to help increase awareness of the importance of sleep and of the negative consequences of poor sleep.

【推荐3】In 1845, a deadly disease struck the farms of Ireland, killing all the Lumper potato plants. In another place or time, the death of a single crop species might not have been so important. But in Ireland, in 1845, people depended almost on the potato for food. The death of one species caused a terrible famine. Now, some scientists are worried that such a famine could happen again.

Over the centuries, farmers have discovered thousands of different species of food crops. Some can be grown in very hot or cold climates. Others are not affected by certain diseases. However, you won’t find many of these species in your local supermarket. To feed the seven billion people on Earth, most farmers today are growing only species of plants that are easy to produce in large numbers. Meanwhile, thousands of other species are becoming extinct.

For example, in the Philippines, there were once thousands of varieties of rice; now fewer than 100 are grown there. Experts believe that over the past century, we have allowed more than half of the world’s food varieties to disappear.

One solution to this problem is to collect and store the seeds (种子) of as many different plant varieties as we can before they disappear. The idea was first suggested by Russian scientist Nikolay Vavilov. In the 1920s and 30s, he collected around 400,000 seeds. More recently, others are continuing the work he began.

In the U.S. state of Iowa, Diane Ott Whealy wanted to protect historic plant varieties. She started a place called Heritage Farm, where people can store and trade seeds.

More importantly, the people at Heritage Farm don’t just store the seeds; they plant them. By doing this, they are reintroducing foods into the marketplace that haven’t been grown for years. These food species are not just special in flavor. They also offer farmers food solutions for the future, from the past.