South Koreans have enjoyed their first close-up look of new baby giant pandas at a name-revealing ceremony that is also     1     early celebration of the 100 days since the twins’ birth.

What to name the twin sisters was widely discussed among netizens after they were born on July 7 in theme park Everland. The names were     2     (ultimate) decided on through two public voting     3     (procedure). One is named Rui Bao, which means wise treasure, and the other is Hui Bao or shining treasure. Half a million panda lovers helped choose their names with a handful of lucky fans     4     (invite) to the ceremony. “They are even     5     (cute) in real life than they appear on screen,” said a college student in attendance.

The baby pandas,     6     have just begun teething and crawling, are very healthy. Everland has shared videos documenting the pandas’ growth online. The twins’ birth has gained 640,000 views since it     7     (upload). “This feels like a great opportunity to call for better     8     (preserve) of pandas,” said Donghee Chung, head of the park’s zoo. Chung noted that between 40% and 50% of panda births result     9     twins.

Everland said it would monitor the twins’ health     10     (determine) when the twins are ready to be open to the public.

3 . Scientists have been experimenting with playing sounds to plants since at least the 1960s, during which time they have been exposed to everything from Beethoven to Michael Jackson. Over the years, evidence that this sort of thing can have an effect has been growing. One paper, published in 2018, claimed that an Asian shrub known as the telegraph plant grew substantially larger leaves when exposed to 56 days of Buddhist music — but not if it was exposed to Western pop music or silence. Another, published last year, found that marigolds and sage plants exposed to the noise of traffic from a busy motorway suffered growth difficulty.

Plants have been evolving (进化) alongside the insects that eat them for hundreds of millions of years. With that in mind, Heidi Appel, a botanist now at the University of Houston, and Reginald Cocroft, a biologist at the University of Missouri, wondered if plants might be sensitive to the sounds made by the animals with which they most often interact. They recorded the vibrations made by certain species of caterpillars (毛毛虫) as they chewed on leaves. These vibrations are not powerful enough to produce sound waves in the air. But they are able to travel across leaves and branches, and even to neighbouring plants if their leaves touch.

They then exposed tobacco plant — the plant biologist’s version of the laboratory mouse — to the recorded vibrations while no caterpillars were actually present. Later, they put real caterpillars on the plants to see if exposure had led them to prepare for an insect attack. The results were striking. Leaves that had been exposed had significantly higher levels of defensive chemicals, making them much harder for the caterpillars to eat. Leaves that had not been exposed to vibrations showed no such response. Other sorts of vibration — caused by the wind, for instance, or other insects that do not eat leaves — had no effect.

“Now speakers with the right audio files are more often being used to warn crops to act when insects are detected but not yet widespread,” says Dr. Cocroft. “Unlike chemical pesticides, sound waves leave no dangerous chemicals.”

4 . New research from the University of Portsmouth has shown a marked increase in shipping in the North East Atlantic. Scientists now warn that more monitoring is required to help protect sea life.

Researchers at the University of Ponsmouth have discovered that rates (率) of shipping in the North East Atlantic area rose by 34 per cent in a five-year period. The research is the first detailed survey of shipping activity in the North East Atlantic. Researchers used data from over 530 million vessel (船) positions recorded by Automatic Identification System(AIS). They looked at the change in shipping between 2013 and 2017 across ten different vessel types. In total the study area covered 1.1 million km², including waters off Belgium, Denmark, France, Germany,Iceland, Ireland, The Netherlands, Norway, Portugal. Spain, and the UK.

Lead author, James Robbins said: “This change is likely to put more pressure on the marine (海洋的) environment, and may influence the protection of at-risk species. Renewed monitoring effort is needed to make sure that protective measures are enough to save species under threat in a changing environment.”

Some of the greatest shipping increases were found in areas close to the Spanish coast. The Espacio Marino de la Costa da Morte saw a rise of 413 percent in vessel activity. It is an area used to protect seabirds.

Dr. Sarah Marley, Visiting Researcher at the University of Portsmouth, said: “Shipping is the most widespread human activity in our oceans, carrying a set of threats-from unnoticeable effects like underwater noise pollution to serious results when ships hit whales.”

Professor Alex Ford. from the University’s Institute of Marine Sciences, said: “Given the well-documented effects that shipping can have on the marine environment, it is necessary that this situation continues to be monitored-particularly in areas used to protect vulnerable (脆弱的) species which may already be under pressure.”

5 . A new study suggests that smoke from wildfires can change how clouds store water and could lead to less rainfall. The research comes as western parts of the United States are currently experiencing drought conditions after several years of intense wildfire activity.

Clouds contain a collection of water droplets (微滴) that form from vapor in the atmosphere. When these droplets condense (凝结) onto each other within a cloud，they become heavier and eventually fall as rain. But the water condensation process requires a solid substance for the vapor to attach to. Different kinds of particles rising up from the Earth’s surface can reach clouds and make this process possible.

The new study found that smoke from wildfires contains small particles that affect the way droplets form in clouds. The main effect was the number of water droplets formed. The team reported that smoky clouds contained about five times the number of droplets as non-smoky clouds. But data also showed that the droplets in smoky clouds were much smaller, about half the size of those in the clouds without wildfire smoke.

It is that size difference, the researchers say, that could reduce the amount of rainfall. This is because small droplets are less likely to grow and eventually fall to the ground as rain. “Because of their small droplet sizes, these smoky clouds are expected to reflect more light and produce less rain than clouds in clean air,” the study states.

The findings could mean that active wildfire seasons in the western U. S. may in fact lead to less rain and more drought, the researchers said. “We were surprised at how effective these primarily organic particles were at forming cloud droplets and what large impacts they had on the microphysics (微观物理) of the clouds,” said Cynthia Twohy, leader of the new study.

Twohy also noted that different kinds of clouds behave differently. The current study examined changes in small cumulus clouds. Other kinds that sit much higher in the atmosphere can cause heavy storms, she said. Twohy added, “I am hoping these results will lead to detailed regional modeling studies that will help us understand the actual impact of smoke on clouds and climate.”

Astronomers have published a major finding    1    (recent): A black hole has been releasing energy from a small star    2    was shredded (吞噬) in 2018, after two years in which it didn’t emit (发射) any such material.

“Super unusual,” said Yvette Cendes, an astronomer at Harvard. “We’ve never really seen this before to this degree.”

Researchers made the    3     (discover) when they used a    4     (power) radio telescope facility to check some two dozen black holes where stars had been shredded after     5    (come) too close to them. Such happenings    6    (call) tidal disruption (潮汐破坏) events, or TDEs.

What they found was that one of the TDEs was emitting energy at an unusual speed    7    at a very surprising time: more than two years after the event.

This behavior is different from what has been observed in black holes before, in two ways. First, the timing: it’s more common    8    (see) radio emissions from black holes within the first few months after swallowing a star. And second, the energy emitted in this case doesn’t quite fit in    9    what astronomers have seen before.

In most cases of black holes swallowing stars, perhaps 99%, the outflow is lower in energy. And in 1% of cases, that outflow, at about half the speed of light, rarely    10     (occur).

8 . A “watch” is the collective noun for nightingales. The term comes from the way nightingales sing from dawn until dusk and into the hours of darkness, keeping watch. It is one of the Britain's best loved but most endangered songbirds, which arrive in spring from West Africa, bringing with them a beautiful song that has inspired poets and musicians from many cultures that the birds have caused over the centuries.

The male nightingales start singing as soon as they return and continue into early June. Rested in the bushes, male nightingales remain unnoticed while their song passes into dark ness to enchant female nightingales and indirectly appeal to human listeners. This combination of performance, beauty, romantic love and night action creates a mythic power that makes nightingales unique among songbirds.

What does a nightingale sound like? Its tune may appeal to human senses but “song” feels like a shorthand description of what the nightingale actually does. The sound comes from the syrinx, an instrument similar to our throat but closer to the bird's heart and which produces an extraordinary range of high and low frequency notes. The nightingale's daytime song is beautiful enough, but as darkness falls and other birds fall quiet, “great jagged   sticks of lyrical music are thrown into the summer night sky”, in the words of poet Simon Armitage and broadcaster Tim Dee in their book, A Poetry of Birds.

The song is also very loud. Ornithologist Tim Birkhead recalls being kept awake all night by a nearby nightingale. At 90 decibels, he could feel its song resonating in his chest. Computer recordings of birdsong can detect sounds of less than one tenth of a second. Human ears can't pick them out but female birds certainly respond to these “sexy-syllables”. Although we don't fully understand the nightingale song, it is one of the most celebrated bird songs in the world, and you can hear it in the UK for a brief period in spring-our guide to the best places to hear a nightingale sing this spring.

Today’s skiers are used to relying on ski lifts at resorts to take them to the top of a mountain before     1     (experience)the addictive thrill of skiing down the mountain.     2    , in some snow-covered villages in Altay prefecture (辖区) of Northwest China’s Xinjiang Uygur Autonomous Region, it’s common in winter to see local herdsmen, with boards     3     (attach) to their feet, climb the snowy slopes without any other forms of assistance.

The pair of boards are wrapped with horsehide(马革),     4     serves a double purpose. Remarkably, the horsehide not only can provide friction (摩擦) to prevent skiers from slipping while going up, but also helps them slide more     5     (smooth)down the slopes.

According to rock carvings uncovered in the area by archaeologists, such     6     (ski) have served for around 12,000 years     7     a means of transportation for the snowfield inhabitants of Altay. The fur skiing boards gradually lost     8     (they) popularity in recent decades after paved roads linked houses to the outside world.

However, Altay plans to protect and promote its skiing culture. The local government department     9     (want) to pass its skiing tradition to future generations. The prefecture is working     10     (develop)the area as a popular destination for skiers and snowboarders. As a result, the ancient fur skiing boards and the craft of making them have found a new lease of life in modern times.