【推荐1】Human tears could carry a flood of useful information. With just a few drops, a new technique can spot eye disease and even glimpse signs of diabetes(糖尿病), scientists report in ACS Nano.

“We wanted to demonstrate the potential of using tears to detect disease,” says Liu Fei, a biomedical engineer at Wenzhou Medical University in China. It's possible that the t cars could open a window for scientists to look into the entire body, he says, and one day even let people quickly test their tears at home.

Tears contain tiny sacs(囊) stuffed with cellular(细胞的) messages. If scientists could capture these microscopic mail bags, they could offer new information on what's happening inside the body.

But collecting enough of these sacs is tricky. Unlike fluid from other body parts, just a trickle of liquid leaks from the eyes.

So Liu's team invented a new way to get the sacs from tiny volumes of tears. First, the researchers collected tears from study participants. Then, the team added a solution containing the tears to a device with two nanoporous membranes(纳米多孔膜), shook the membranes and sucked the solution through. Within minutes, the technique lets small molecules(分子) escape, leaving the sacs behind for analysis. The result surprises scientists very much. Different types of dry-eye disease left their own molecular fingerprints in people's tears, the team found. What's more, tears could potentially help doctors monitor how a patient's diabetes is progressing.

Now, the scientists want to make use of tears for evidence of other diseases as well as depression or emotional stress, says study coauthor Luke Lee, a bioengineer at Harvard Medical School. “This is just the beginning.” he says, “Tears express something that we haven't really explored.”

【推荐2】In the future, people may travel to Mars（火星)by water-powered spaceship! Today's spaceships are fine for getting things into space, but they are not so good at travelling long distances. These spaceships burn chemical fuels(燃料)and they are very expensive. Scientists say that a water-powered spaceship could make the trip to Mars much cheaper. The idea is just in the planning stages now, but scientists think such a spaceship could be developed soon.

The key to the water-powered spaceship is the engine(发动机).Regular engines push spaceships by burning fuel. The water engine will use steam, created by solar panels(太阳能板)that heat water to a high temperature. Of course, the spaceship will have to carry a lot of water for the long trip to Mars.

Today's spaceships could not carry that much water. But scientists think that a spaceship blown up like a balloon will be able to.

One Us company has already developed a spaceship like this. These spaceships are made of a strong material. Two of them have already been sent up into space, using rockets and then later filed with air. “Balloon” spaceships could be very large and carry enough water for a long trip. With the “Balloon” spaceships, enough water could be carried to power the engines and grow food during the trip. And the people on the spaceship might even get to take a hot bath!

Scientists say the biggest advantage of such a spaceship would be cost. The “Balloon” spaceship uses water to push it through space and costs about one thirtieth of a normal spaceship. Such savings naturally encourage continued research into balloon spaceships and water engines. If these scientists are correct, we may soon be on our way to Mars in a spaceship powered by water.

【推荐1】The Horn of Plenty is one of the largest natural health food stores within the Greater Hamilton area. We are big supporters of buying locally and we are here to tell you why it is so important for your family, the community and the environment.

The concept of buying locally is simple: buy food produced, grown, or raised as close to your home as possible. Not only will your food be fresher and tastier, but you are helping protect the environment and are supporting businesses within your community and reducing pollution.

Better for the Environment

Sustainability(持续性) and global warming are such hot topics at the moment, and many people want to do their bit to help support a healthier environment. Small action carried out by many people can make a big difference. Most materials in an average North American meal have traveled about 1,500 miles to get from farm to plate. To cut out a big part of this travel would greatly reduce not only pollution from transportation and refrigeration but also customers’ expenses as well.

Taste and Nutritional Content

Locally-grown fruits and vegetables are usually sold within 24 hours of being harvested. Because they are picked at the height of ripeness and travel only a short distance to the market, their freshness, nutrition, and flavor are kept. Produce trucked in from far away may lose both taste and nutritional content.

Community and Home Values

When you buy direct from a farmer or buy locally-grown foods, you are engaged in a time-honored tradition between a grower and an eater. You also help keep dollars within your community.

【推荐2】The early life of the green sea turtle (海龟) is full of danger. Only one in 1,000 baby sea turtles survive to adulthood (成年). From its home in the sand, it breaks its egg with an egg tooth. Its mother is not there to help it. Instead, it is greeted by crabs, coyotes, and dogs waiting to eat it for dinner. To survive, the baby turtle must hide in the sand until night. Then, it moves slowly to the sea.

The small turtle must swim hard to reach the ocean waters. In the sea, it tries hard to find food. It must also keep itself from being food for fish.

As dangerous as the sea turtle’s life is in the natural world, its most dangerous enemies are humans. The rubbish left by humans in the ocean causes problems for the small green sea turtle. A little turtle might eat a piece of plastic (塑料) in the sea. It might also eat oil on the ocean’s surface. Young turtles also get caught in fishing nets. There are laws against hunting sea turtles. Still, many are hunted, both for their meat and for their shells (壳). All of these dangers must be prevented.

Sea turtles that do survive to grow into adulthood go through many changes. For example, adult green sea turtles weigh about 500 pounds. They stop eating jellyfish and other meat and eat only plants. And they may plan a trip to go back home again. A mother sea turtle goes back to the beach where she was born. This is the only place where she will lay eggs. Even if it has been forty years since she was a baby, she always knows her way back home.