【推荐2】Swimming alongside wild dolphins has long been on the Hawaii vacation list. However, scientists are concerned that increased human activities may do bad to the animals by disturbing a very important period of their rest. “We have seen changes in their action,” Ann Garrett of NOAA’s National Marine Fisheries Service said. “They will be more active with people around.”

After feeding in deep water at night, dolphins return to sheltered, shallow (浅的) water to rest during the day. The problem appears when swimmers draw them out of their resting state, a change in behavior that NOAA points out “may cause disturbance”.

“Disturbing their resting behaviors can actually affect their long-term health and the health of the population,” Garrett said. This summer, NOAA is set to put forward its new rules. “NOAA is considering a lot of measures. These measures may make some people angry, but they will undoubtedly do good to those dolphins,” Garrett said.

Today, a small number of Hawaii tour companies willingly join in a NOAA program called Dolphin SMART. Designed to lower the disturbance that dolphins suffer because of human activities to the minimum (最低限度), the program encourages tourists to stay 50 yards away from dolphins and to move away carefully if they feel the animals are disturbed.

NOAA’s new rules, however, would not be allowed to be chosen to follow or not, and could affect over 200 dolphin-related businesses as well as swimmers and other ocean users. Garrett said that new rules would keep tour companies from disturbing dolphins. “The final goal of the changes,” she said, “will be to provide more protections for dolphins while still offering a chance for tourists to have a pleasant wildlife experience”.

【推荐3】The drone (无人机) is flying above the Amazon River in Brazil, but its battery is running low. Andre Coelho, the chief pilot, guides it back to safety with skills perfected by playing video games. Long hours’ practicing has become a surprising benefit in an effort to conserve dolphins that live in the river. Marcelo Oliveira, a conservation specialist, stands on the bow of a boat. He pulls the white drone from the air, changes the battery, and quickly sends it back in the sky.

Later, scientists will examine the video which has recorded for signs of the two species of dolphins that inhabit the river: the pink and bulbous boto (亚马孙河豚), and the smaller, prettier tucuxi (白海豚). Exactly how many live in the basin is a mystery. Some studies have suggested a decline of the pink dolphins in specific areas of the Amazon River, but the International Union for Conservation of Nature (IUCN) says there isn’t enough data available for either species of dolphins.

“We need to base everything on hard data,” says Miriam Marmontel, a scientist. “We need to focus on what’s really critical to help us get to a real situation that can influence policy. We need numbers. We need information on death and reproduction.”

Marmontel’s biggest concern is that dolphins are being caught in the nets of local fishermen. Scientists have also given a warning against fishermen’s killing botos. Pollution from gold mining is also a concern.

The scientists want to use the information they collect to persuade the IUCN to list the boto and the tucuxi as endangered species. Funding agencies and governments want evidence. Without the IUCN’s categorization, it’s difficult to raise the money for protection measures.

They hope their drone monitoring will do the trick. During three trips to the Amazon last year, the team has recorded about 70 samples (样本) that will contribute to a more accurate estimate of dolphin populations in the Amazon basin.

【推荐1】Listening to an audiobook (有声书) before bed affects a person’s brain activity after they nod off as well as the content of their dreams.

Better understanding this effect could help treat certain mental health conditions by targeting memory processing during sleep. When we sleep, our brain spontaneously (自发地) “replays”, or reactivates patterns of electrical activity that are related to learning to transfer important new information to long-term memory storage. It has been suggested that dreams may reflect this reactivation, but exactly how is unclear.

To investigate, Deniz Kumral at the University of Freiburg, Germany, and her colleagues asked 20 people to listen to different audiobooks just before they went to sleep. These included The Mystery of the Blue Train by Agatha Christie and Inkheart by Cornelia Funke.

Among the participants who remembered their dreams, the researchers could identify which audiobook each had heard from their descriptions of the dreams. While the participants slept, the researchers also used an EEG (脑电图) cap that detects electrical activity to record their brain waves. This showed that the wave patterns during the rapid eye movement phase of sleep, when dreams occurred, were more similar between those who had heard the same audiobook than those who had heard different ones, suggesting that the listening experience shaped the brain activity.

Further analysis of the patterns revealed that high-frequency beta waves — between 18 and 30hertz — were most strongly associated with the participants recalling the audiobook-related content of their dreams. The findings suggest that daily life experiences can shape dream content via memory reactivation, according to the researchers. But while dreaming may serve a distinct purpose in memory formation, it could also be a by-product of memory processing.

“Daytime experiences are rarely replayed as experienced, but are almost always modified or surface in different contexts,” says Kumral. “Individuals with certain psychological conditions or mental problems might benefit from tailored strategies that enhance memory processing or treat disorders of dreaming during sleep, potentially contributing to improved mental and emotional health.”

【推荐3】Landfills are where most of the world’s plastics end up and a fair amount of it ends up in the world’s oceans. But a new British recycling firm wants it to end up here.

There is a great demand right now for recycled material. There’s a great deal of interest in getting recycling into the plastics industry specially, and so we are really going to further the ability to get plastic into the circular economy.

The firm called Recycling Technologies is breaking down plastic, then turning it into fuel oils or raw material to make new plastics. Basically, currently all we do is we make a hydrocarbon soup and then we take the materials out at different temperatures, so the higher temperatures, the waxes separate out, then we cool it a bit more, and the heavy oils then we call it, a bit more the light oils, and then the rest comes out. It’s naphtha, the gases that don’t condense (凝结) out. We actually use the fuel for the process. Their process is creating a heavy fuel oil that works for marine vessels (海洋船舶). We call it a clean material, because it has very little sulfur in it, in fact almost none, which certainly also fits with the new regulations for marine fill, where they’re asking for much lower sulfur around the world. So it’s a very valuable product.

Right now, the firm is recycling about 7,000 tons of plastic a year, but says it can quickly increase. We are designing to a four-day installation (装置). We will basically come in six ice-free containers which will stand on end, fixed together, and we plug in play mode and the aim is to be up and running within four days. So this is definitely not a refinery (提炼厂) concept.

This is much more a piece of stand-alone industrial equipment. The company has set the ambitious goal of selling 1300 of their recycling units around the world during the next decade, and expect they will be able to recycle 9 million tons of plastic each year.