【推荐1】The wires, screens and batteries that make up our devices-not to mention the plastic, metal and other materials that package them-are filling up landfills. Some e-waste is relatively large: old phones and air conditioners, for instance. Other e-waste is more hidden, such as electronic single-use medical diagnostic kits, environmental sensors, and smart labels that contain one-off batteries and other equipment.

“It’s these small batteries that are big problems, ” says public health scientist Dele Ogunseitan, who was not involved in developing the battery. ”Nobody really pays attention to where they end up.

Researchers at the Cellulose & Wood Materials Laboratory at the Swiss Federal Laboratories for Materials Science and Technology (Empa) are working to address this problem. Their new paper in Scientific Reports describes a paper battery developed from environmentally friendly materials that could eventually present a sustainable alternative to the more harmful batteries common in low-power devices.

The paper battery has the same key components as standard batteries but packages them differently. Like a typical chemical battery, it has-a positively charged side called a cathode (正极), a negatively charged side called an anode (负极), and a conductive material called an electrolyte (电解质)between the two. A traditional battery’s components are packaged in plastic and metal; in the new battery, the anode and cathode are inks printed onto the front and back of a piece of paper. That paper is filled with salt, which dissolves (溶解)when the paper is dampened with water. The resulting saltwater solution acts as the electrolyte.

When the paper is dry, the battery is shelf-stable. Add just a couple of drops of water, however, and the salt dissolves, allowing electrons to flow. Once the paper is dampened, the battery becomes active within 20 seconds. The new battery’s operating performance declines as the paper dries. When the scientists rewet the paper during testing, the battery regained functionality and lasted an hour before beginning to dry out again.

【推荐1】Honeybees are in trouble. While they’ re crucial for promoting biodiversity and producing food for healthy human diets, honeybees face many threats, including habitat loss, climate change, air pollution and disease-causing organisms.

But now, there’s hope for helping honeybees fight back against one of the many stressors they face, a deadly infectious disease known as American foulbrood. To fight the disease, the U.S. Department of Agriculture approved for use the world’s first honeybee vaccine (疫苗), developed by Dalan Animal Health.

Bacteria called Paenibacillus larvae cause American foulbrood, which kills honeybees while they are in the pupal (蛹的) or pre-pupal stage. Until now, there was no “safe and sustainable” way to prevent American foulbrood. The only treatment involved antibiotics (抗生素), which are expensive, have limited effectiveness and take lots of time and energy for beekeepers to apply. To stop the spread, beekeepers are often forced to burn infected bees. That makes the vaccine a game changer.

“Our vaccine is a breakthrough in protecting honeybees,” says Annette Kleiser, CEO of Dalan Animal Health. “We are ready to change how we care for insects, impacting food production on a global level.”

Beekeepers will mix the vaccine, which contains dead P. larvae bacteria cells, into the food that worker bees eat. Then, when the worker bees produce their milky royal jelly (蜂王浆), the queen will eat it and the vaccine. Then, the vaccine will protect her developing offspring from the disease.

Under a conditional license from the USDA, Dalan Animal Health now plans to distribute limited amounts of the vaccine to commercial beekeepers. From there, they hope to offer it for sale throughout the U.S. sometime this year.

The federal agriculture agency awards conditional licenses to products that meet an emergency, situation, limited market, local situation or special circumstance. The USDA requires products that receive these types of licenses to be pure and safe, and have a reasonable expectation of effectiveness. Generally, conditional licenses come with restrictions and cover a limited period of time. Once that period ends, the agency evaluates the product’s effectiveness to determine whether to renew the conditional license or award a regular product license.

【推荐3】Silkworms(蚕)were first brought from Asia to the ancient city of Byzantium around A. D. 550. It was two men who presented some silkworm eggs from China to Byzantine Emperor Justinian I in Constantinople, where he created a fruitful silk industry. Silkworms reached Italy through Sicily in the 12th century, and by the 13th century, silkworm farming had moved north to the Po River Valley. By the 16th century, silkworm farming had been introduced to the Como area.

Since silkworms require a constant, mild temperature, entire sections of farmhouses were turned over to them and whole families would often join in the work, adding fuel round the clock to fires to maintain the proper warmth. “Some even gave the worms the house and slept outside with the animals, ”says Ester Geraci, an official at Como’s Educational Silk Museum.

The process began with the 10-to 14-day incubation(孵化)of silkworm eggs. According to the museum, keeping the tiny, delicate eggs at just the right temperature was the task of the women. Once hatched, the worms, only about one millimeter long, had to be fed night and day. From a birth weight of only half a milligram, they would grow 10, 000-fold to a final weight of around five grams and a length of 8 to 9 centimeters in just 30 days. Then, in the final three days of their youth stage, the worms would start to make their cocoons (茧) out of one continuous thin silk-up to 1, 200 meters long-which they produced from near their mouths. After about a week, the cocoons were placed briefly in a hot, dry place to kill the adult insects inside. These cocoons were then put in hot water to facilitate the difficult and boring task of obtaining the silk. The minute end of the cocoon’s silk had to be located and placed onto a round object, which then unwound it from the water-warmed cocoon. The silk was then cleaned and made into fabric.