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[阅读小分队] 【Native Speaker每日训练计划】No.2769科技

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发表于 2020-5-4 19:47:22 | 显示全部楼层 |阅读模式
内容:Chopin Hong 编辑:Carrie Qin
Wechat ID: NativeStudy  / Weibo: http://weibo.com/u/3476904471
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Part I: Speaker

Virus-Infected Bees Practice Social Distancing
By Karen Hopkin on April 30, 2020

Bees infected with a virus cut back on interactions within their hive but find it easier to get past sentries at neighboring hives.

Source: Scientific American
https://www.scientificamerican.com/podcast/episode/virus-infected-bees-practice-social-distancing/

[Rephrase 1, 03:24]

Part II: Speed



Why mammals like elephants and armadillos might get drunk easily
By Susan Milius
MAY 1, 2020

[Time 2]
An elephant, a narwhal and a guinea pig walk into a bar. From there, things could get ugly.

All three might get drunk easily, according to a new survey of a gene involved in metabolizing alcohol. They’re among the creatures affected by 10 independent breakdowns of the ADH7 gene during the history of mammal evolution. Inheriting that dysfunctional gene might make it harder for their bodies to break down ethanol, says molecular anthropologist Mareike Janiak of the University of Calgary in Canada.

She and colleagues didn’t look at all the genes needed to metabolize ethanol, but the failure of this important one might allow ethanol to build up more easily in these animals’ bloodstreams, Janiak and colleagues report April 29 in Biology Letters.

The carnivorous cetaceans, grain- or leaf-eating guinea pigs and most other animals that the study identified as potentially easy drunks probably don’t binge on sugary fruit and nectar that brews ethanol. Elephants, however, will feast on fruit, and the new study reopens a long-running debate over whether elephants truly get tipsy gorging on marula fruit, a relative of mangoes.

Descriptions of elephants behaving oddly after binging on overripe fruit go back at least to 1875, Janiak says. Later, a taste test offering the animals troughs of water spiked with ethanol found that elephants willingly drank. Afterward, they swayed more when moving and seemed more aggressive, observers reported.

Yet in 2006, physiologist Steve Morris of the University of Bristol in England and colleagues attacked the notion of elephant inebriation as “a myth.” Among their arguments was a calculation that even if African elephants really were feasting on fallen, fermenting marula fruit, the animals could not physically eat the huge amount necessary at one time to get a buzz. However, that calculation extrapolated from human physiology. The new insight that elephants’ ADH7 gene doesn’t work might mean they have a lower tolerance for the tipple.
[315 words]

[Time 3]
It wasn’t elephants, though, but tree shrews that inspired the new work. They look like “cute squirrels with pointed noses,” says senior author Amanda Melin, a biological anthropologist also at Calgary, and they have a prodigious tolerance for alcohol. Concentrations of ethanol that would make a human sloppy apparently don’t phase the little animals. She, Janiak and colleagues decided to survey all of the mammal genetic information that they could find to indirectly assess the variety of responses to alcohol. “We were on a patio drinking beer when we first sketched out the paper,” Janiak remembers.

Looking at genetic information available on 79 mammal species, researchers found that ADH7 has lost its function in 10 separate spots on the mammal family tree. These ethanol-susceptible twigs sprout quite different animals: elephants, armadillos, rhinos, degus, beavers and cattle among them.

In contrast, humans and nonhuman African primates have the reverse situation, a mutation that renders their ADH7 some 40 times more efficient at dismantling ethanol than a typical mammalian version. Aye-ayes, with diets rich in fruit and nectar, have independently evolved the same trick. What gives tree shrews their drinking superpower, however, remains a mystery since they don’t have the same superefficient gene.

Finding the gene dysfunction in the African elephant, however, raises questions about the old inebriation arguments. A slower capacity for clearing ethanol from the body could mean that the smallish amount that an elephant gets from eating its full of fermented fruit might be enough to change their behavior after all, Melin says.

Behavioral ecologist Phyllis Lee has been watching elephants in Kenya’s Amboseli National Park since 1982 and is now director of science for Amboseli Trust for Elephants. “In my youth, we tried to brew a form of maize beer (we were desperate), and the elephants loved to drink it,” she says. She does not take sides in the myth debate, although she muses about the “huge liver” of elephants, which would have at least some detoxifying power.

“I never saw one that was tipsy,” Lee says, although that home brew “didn’t do much for us puny humans either.”
[351 words]

Source: Science News
https://www.sciencenews.org/article/why-mammals-elephants-armadillos-might-get-drunk-easily



Greenland and Antarctica are gaining ice inland, but still losing it overall
By Maria Temming
APRIL 30, 2020

[Time 4]

In the tug-of-war between coastal melting and inland ice buildup, the meltdown is winning in both Greenland and Antarctica.

Initial observations from NASA’s ICESat-2 satellite in 2018 and 2019 reveal how the Greenland and Antarctic ice sheets have changed since the original ICESat mission collected data from 2003 to 2008. Both missions measured the height of ice near Earth’s poles by bouncing laser light off the surface. Since each satellite’s position in space was known, clocking how long it took reflected light to return to the satellite revealed the ice’s height, allowing researchers to discern changes in ice thickness between measurements.

These data indicate that ice in eastern Antarctica and central Greenland thickened slightly from 2003 to 2019. The researchers suspect this is the result of increased snowfall, because in a warmer climate, more ocean water evaporates and the air holds more moisture. But a minor thickening of inland ice was no match for the massive ice losses along Greenland and Antarctica’s coastlines, researchers report online April 30 in Science. Greenland and Antarctica lost an average 200 billion and 118 billion metric tons of land ice per year, respectively, over this 16-year period.

In terms of where and how each ice sheet lost mass, “the Greenland and Antarctic ice sheets are two very different beasts,” says study coauthor Alex Gardner, a glaciologist at NASA’s Jet Propulsion Laboratory in Pasadena, Calif.

Ice all around the coast of Greenland thinned drastically, due to warmer summer temperatures. But the most severe thinning happened on Greenland’s outlet glaciers, which are like “a whole bunch of little fingers that spread out into the ocean,” Gardner says. Where the tips of these glacial fingers poke out from between cold fjords and meet warmer ocean water, that water erodes the ice, causing the glaciers to flow out faster and thin inland. Greenland’s southern Kangerdlugssuaq and Jakobshavn glaciers have thinned most rapidly — by 4 to 6 meters of ice thickness per year.

In Antarctica, warmer seawater not only melts glaciers, but it also melts the extensions of the ice sheet that float on the ocean, called ice shelves, which surround the continent. Melting ice shelves do not directly contribute to sea level rise, for the same reason a melting ice cube doesn’t overflow a glass of water. But ice shelves resist the natural flow of Antarctica’s inland ice from the heart of the continent toward the coasts. As ice shelves thin and weaken, they let ice flow into the ocean faster than snowfall keeps up, raising sea levels. Antarctic ice has especially thinned in the western Amundsen and Bellingshausen regions.

ICESat-2’s detailed observations of Antarctica and Greenland’s ice loss were “eagerly anticipated,” says Andrew Shepherd, a climate scientist at the University of Leeds in England who was not involved in the study. Such a detailed record of ice changes can be used to test the predictions of past climate models, helping researchers understand how to make forecasting tools more accurate, he says.
[494 words]

Source: Science News
https://www.sciencenews.org/article/greenland-antarctica-are-gaining-ice-inland-losing-melting-overall



The sun is less magnetically active than similar stars, and we don’t know why
By Lisa Grossman
APRIL 30, 2020

[Time 5]

The sun might be a magnetic slacker.

A census of stars similar to the sun shows that our own star is less magnetically active than others of its kind, astrophysicists report in the May 1 Science. The result could support the idea that the sun is in a “midlife crisis,” transitioning into a quieter phase of life. Or, alternatively, it could mean that the sun has capacity for much more magnetic oomph than it’s shown in the past.

“Our sun could potentially become [as] active” as those other stars in the future, says astrophysicist Timo Reinhold of the Max Planck Institute for Solar System Research in Göttingen, Germany.

A star’s magnetism can drive dramatic outbursts like flares and coronal mass ejections, which can cause chaos on orbiting planets. When these large ejections from the sun hit Earth, they can knock out satellites, shut down power grids and trigger beautiful auroras. Understanding the sun’s magnetic field is thought to be the key to predicting such outbursts.

Magnetic fields also can create dark sunspots and bright spots called faculae on a star’s surface. These features change over time as magnetic activity changes, altering a star’s brightness.

Astronomers have been observing the sun’s magnetism through those surface features since Galileo turned a telescope toward the sun in 1610. While the sun’s magnetic activity waxes and wanes in an 11-year cycle, our star has remained fairly calm while humans have been watching. Inferences from certain radioactive elements found in tree rings and ice cores suggest that same overall cycle of magnetic activity has held steady for the last 9,000 years.

Because other stars are so far away, tiny changes in brightness that reveal magnetic changes were hard to detect until 2009, when the Kepler space telescope launched. The now-defunct telescope found exoplanets by picking up on slight dips in starlight as planets orbited in front of stars, but the spacecraft’s data include a wealth of information on other changes in stars’ brightness.
[328 words]

[Time 6]

To see how the sun’s brightness compared with its stellar kin from 2009 to 2013, Reinhold and his colleagues studied stars whose age, surface gravity, chemical makeup and temperature are similar to the sun’s. The team also sought stars that rotate at nearly the same rate as the sun, roughly once every 24 days.

Not every star’s rotation period was measurable, so Reinhold’s team split the stars into two groups: 369 “solarlike” stars, with rotation periods between 20 and 30 days, and 2,898 “pseudo-solar” stars, whose period could not be detected.

Surprisingly, although the stars with no detectable rotation periods looked as magnetically calm as the sun, the stars with sunlike rotations were up to five times as active.

Either something is different about those stars, Reinhold says, or the sun may go through periods of greater variability in its brightness — and thus, magnetic activity — that scientists just haven’t seen. Perhaps “the sun did not reveal its full range of activity over the last 9,000 years,” he says. “The sun is 4.5 billion years old; 9,000 years is nothing.”

Still another explanation for the finding is related to the idea that stars might stop slowing their rotation because of a midlife change in their magnetic field, says astronomer Travis Metcalfe of the Space Science Institute in Boulder, Colo.

Many stellar physicists think that stars continually lose momentum and slow their spins as they get old. But in 2016, Metcalfe and colleagues reported that Kepler was seeing stars that rotate too fast for their advanced ages. The team suggested that stars might stop their slowdowns at middle age, and that the sun is currently going through this transition.

The new result “could be the best evidence yet that the sun is in the midst of a magnetic midlife crisis,” Metcalfe says. The hyperactive stars in Reinhold’s sample appear to be slightly younger than the sun, and so may not have gone through their magnetic transition yet. The sun and the other calmer stars could already be on the other side.

“It’s super interesting either way it turns out,” Metcalfe says.
[349 words]

Source: Science News
https://www.sciencenews.org/article/sun-less-magnetically-active-than-similar-stars


Part III: Obstacle


What Rome Learned From the Deadly Antonine Plague of 165 A.D.
By Edward Watts, Zócalo Public Square   |  SMITHSONIANMAG.COM  |  April 28, 2020

[Paraphrase 7]
Around 165 A.D., the Anatolian town of Hierapolis erected a statue to the god Apollo Alexikakos, the Averter of Evil, so that the people might be spared from a terrible new infectious disease with utterly gruesome symptoms. Victims were known to endure fever, chills, upset stomach and diarrhea that turned from red to black over the course of a week. They also developed horrible black pocks over their bodies, both inside and out, that scabbed over and left disfiguring scars.

For the worst afflicted, it was not uncommon that they would cough up or excrete scabs that had formed inside their body. Victims suffered in this way for two or even three weeks before the illness finally abated. Perhaps 10 percent of 75 million people living in the Roman Empire never recovered. “Like some beast,” a contemporary wrote, the sickness “destroyed not just a few people but rampaged across whole cities and destroyed them.”

Smallpox had hit Rome.

Infectious disease was long part of Roman life. Even the richest Romans could not escape the terrors of a world without germ theory, refrigeration, or clean water. Malaria and intestinal diseases were, of course, rampant. But some of the ailments Romans suffered boggle the mind—vicious fevers, wasting diseases and worms living in putrefying wounds that refused to heal. The physician Galen would recall a member of the Roman gentry who accidentally drank a leech when his servant drew water from a public fountain. The 4th-century emperor Julian found it a particular point of pride that he had only vomited once in his entire life. By the standards of antiquity, this was a bona fide miracle.

But smallpox was different. Rome’s first smallpox epidemic began as a terrifying rumor from the east, spreading through conversations that often simultaneously transmitted both news of the disease and the virus itself. The pathogen moved stealthily at first, with people first showing symptoms two weeks or so after contracting it.

The plague waxed and waned for a generation, peaking in the year 189 when a witness recalled that 2,000 people died per day in the crowded city of Rome. Smallpox devastated much of Roman society. The plague so ravaged the empire’s professional armies that offensives were called off. It decimated the aristocracy to such a degree that town councils struggled to meet, local magistracies went unfilled and community organizations failed for lack of members. It cut such deep swaths through the peasantry that abandoned farms and depopulated towns dotted the countryside from Egypt to Germany.

The psychological effects were, if anything, even more profound. The teacher Aelius Aristides survived a nearly lethal case of the plague during its first pass through the empire in the 160s. Aristides would become convinced that he had lived only because the gods chose to take a young boy instead; he could even identify the young victim. Needless to say, survivor’s guilt is not a modern phenomenon—and the late 2nd century Roman Empire must have been filled with it.

Most of all, though, the disease spread fear. Smallpox killed massively, gruesomely, and in waves. The fear among Romans was so pronounced back then that, today, archaeologists working all over the old imperial territory still find amulets and little stones carved by people desperately trying to ward off the pestilence.

In the face of smallpox’s sustained assault, the resilience of the empire amazes. Romans first responded to plagues by calling on the gods. Like Hierapolis, many cities across the Roman world sent delegations to Apollo, asking for the god’s advice about how to survive. Towns dispatched the delegates collectively, an affirmation of the power of community to stand together amidst personal horror.

And when communities began to buckle, Romans reinforced them. Emperor Marcus Aurelius responded to the deaths of so many soldiers by recruiting slaves and gladiators to the legions. He filled the abandoned farmsteads and depopulated cities by inviting migrants from outside the empire to settle within its boundaries. Cities that lost large numbers of aristocrats replaced them by various means, even filling vacancies in their councils with the sons of freed slaves. The empire kept going, despite death and terror on a scale no one had ever seen.

Roman society rebounded so well from smallpox that, more than 1,600 years later, the historian Edward Gibbon began his monumental Decline and Fall of the Roman Empire not with the plague under Marcus Aurelius but with the events after that emperor’s death. The reign of Marcus was, to Gibbon, “the period in the history of the world during which the condition of the human race was most happy and prosperous.” This historical verdict would have astounded Romans if they’d heard it back when they suffered through what came to be called the Antonine Plague. But Gibbon did not invent these sentiments. Writing after the turn of the 3rd century, the Roman senator and historian Cassius Dio called the empire under Marcus “a kingdom of Gold” that persevered admirably “amidst extraordinary difficulties.”

Cassius Dio witnessed smallpox’s effect in Rome when it killed most spectacularly. Dio knew its horrors and the devastation it produced. He also believed that the trauma of living through plague can be overcome if a well-governed society works together to recover and rebuild. And the society that emerges from those efforts can become stronger than what came before.

COVID-19 has brought about the first time that much of our world has faced the sudden, unseen, and unremitting fear of an easily spread and deadly infectious disease. Such a crisis can spur terrified citizens to blame each other for the suffering. It can exacerbate existing social and economic divisions. It can even destroy societies. But that need not be so.

The Antonine Plague was far deadlier than COVID-19, and the society it hit was far less capable of saving the sick than we are now. But Rome survived. Its communities rebuilt. And the survivors even came to look back on the time of plague with an odd nostalgia for what it showed about the strength of their society and its government.

May we be so lucky.
[1016 words]

Source: Smithsonian
https://www.smithsonianmag.com/history/what-rome-learned-deadly-antonine-plague-165-d-180974758/

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发表于 2020-5-4 20:43:32 发自手机 Web 版 | 显示全部楼层
T2:3:49
T3:2:46
T4:3:24
T5:3:51
T6: 3:26
T7:6:50
发表于 2020-5-4 23:56:11 | 显示全部楼层
New words: binge on  tipsy  inebriation  Aye-ayes  smallish  puny
00:00
Lack of certain gene may cause disability of metabolizing alchohol.
03:14
Though survey of  all mammal genetic information, scientists have found 10 species that lack this gene.
02:32
NASA used satallite to detect the icebergs in the north pole. They found that snowfall-caused thicken ice were  no macth for the massive ice losses.
03:33
Situations of ice in G and  A  are different. Warmer seawater melt glaciers and ice shelves, then ice flow fasters hence rasing the sea level.
01:28
The sun is in a “midlife crisis,” transitioning into a quieter phase of life.
02:01
By studying gravity chemical makeup and temperature of stars who are like the sun , scientist found sun is especially calm. This phenomenon may due to differences between the sun and other stard, or greater vriability in the sun's brightness of sun. Another explanation is that the sun rotates slower than before.
发表于 2020-5-5 01:06:13 发自 iPhone | 显示全部楼层
T2 有研究表明大象等动物非常容易喝醉 因为难以降解酒精
T3 相比大象等动物 人类具有某种基因 更能有效降解酒精
发表于 2020-5-5 01:27:07 | 显示全部楼层
T2:2,12
T3 2 04
T4 2 43
T5 2'11
T6 2'07
发表于 2020-5-5 05:44:06 | 显示全部楼层
[Time 2] 5:55
Studies show that elephants are likely to get drunk by eating overripe fruits.
[Time 3] 6:49
Some scientists find that the evolution and the differentiation rendered elephants easily to drunk, but others have observed different phenomena.
[Time 4] 7:55
Although the inland ice in Antarctica and Greenland is increasing, it cannot offset the ice sheet melting beside the coast. Notably, the ice shelves in inland Antarctica would dramatically raise the ocean level.
[Time 5] 5:32
The level of our sun`s magnetic activity is lower than it should be. Then the author introduced the phenomena caused by magnetic activity, the cycle of the sun`s activity, and the observation history of the sun`s activity.
[Time 6] 5:51
The stars have a similar self-rotation cycle to the sun, often are five times activity than the sun. Then the author cast a new theory about the relationship between the age and the rotation speed, which can not explain why the sun is less activity.
发表于 2020-5-5 09:13:47 | 显示全部楼层
T2 2'12''
T3 2'07''
T4 2'34''
T5 2'19''
T6 2'37''
T7 5'21''
发表于 2020-5-5 10:05:43 | 显示全部楼层
Obstacle: 17’47”

Main idea:
People in ancient times did not know how to deal with infectious diseases correctly because of poor scientific knowledge. However, Rome survived through the plague, smallpox, even though people still did not develop science. It is taught that if society can be well governed, human beings can beat the pandemic (COVID-19).

Paraphrase:
In the ancient time of Rome, people pledged to the God Apollo, trying to survive the infectious disease in H. Also, (it left ugly scars on the patient body; nearly 10% of people were infected and unrecovered).

(Although Romans survived in some ailments luckily), afterward, smallpox began to be epidemic in Rome. At first, it was a rumor but people were getting symptoms after two weeks they heard about the rumor. The victims suffered from fever, chill…, and like how people in the back time reacted to the H, they ask God for advice on how to overcome the disease.

The infectious disease was unknown to people at that time. The hardest time happened in XXXX (189), when 1600(2000) people died every day. Even aristocracy could not get to avoid the disease. As a result, the farmland was left empty, and the population decreased dramatically.

Furthermore, the other effect of the plague was fear. One of the archaeologists found the stone from that time curved with desperate words.

To live through the epidemic, the empire formed a new army by recruiting slaves. In addition, the empire allowed the son of freed slaves to inherit the legacy from the dead aristocracy.

Now the COVID-19 makes people scary again. However, Rome can get through the plague, contemporary society must be able to do this again if people would be willing to rebuild together.

Vocabulary:
Gruesome: causing repulsion or horror, grisly
Bona fide: genuine, real, sincerely
Ward off: avoid
发表于 2020-5-5 10:14:01 | 显示全部楼层
T2: 2'44
T3: 2'49
T4: 3'47
T5: 2'47
T6: 1'31
OBSTACLE: 6'03
发表于 2020-5-5 11:12:57 | 显示全部楼层
[Time 2]        2‘05
[Time 3]        2‘15
[Time 4]        3‘09
[Time 5]        2‘03
[Time 6]        1‘58
[Paraphrase 7]        6‘20
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