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[阅读小分队] 【Native Speaker每日训练计划】No.2849 科技

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发表于 2020-7-28 19:34:59 | 显示全部楼层 |阅读模式
内容:Alice Ge 编辑:Alvin Wei

Wechat ID: NativeStudy  / Weibo: http://weibo.com/u/3476904471




Part I: Speaker

Science News Briefs from Around the Planet
By Sarah Lewin Frasier on July 26, 2020 [Rephrase 1, 02:05]

Source: Scientific American
https://www.scientificamerican.com/podcast/episode/science-news-briefs-from-around-the-planet1/


Part II: Speed



Masks help new moms with COVID-19 safely breastfeed their babies
By Aimee Cunningham | JULY 23, 2020 AT 6:53 PM

[Time 2]
Mothers with COVID-19 at delivery can breastfeed their newborns without passing along the infection, as long as they take certain safety precautions.

Wearing a surgical mask while nursing and cleaning hands before handling their babies kept the coronavirus from spreading from mothers to their infants, a new study finds. It adds to a growing body of evidence that suggests babies are rarely becoming infected after birth and getting severely ill from the virus.

The study took place at three hospitals in New York City, the initial epicenter of the U.S. outbreak. Doctors identified 120 babies born from late March to mid-May to 116 women who were positive for SARS-CoV-2, the virus that causes COVID-19. After donning surgical masks (SN: 6/26/20) and cleaning hands, the mothers could hold their babies within the first hour of birth. Early skin-to-skin contact promotes bonding and breastfeeding and has other health benefits.

None of the babies were positive for SARS-CoV-2 when tested a day after they were born, researchers report online July 23 in the Lancet Child & Adolescent Health. Seventy-nine of the babies were tested for the virus five to seven days after birth, by which time many had been discharged to their homes, with guidance for parents on continuing infection control. All of these infants tested negative. At this point, 64 were still breastfeeding or getting breastmilk from a bottle.
[227 words]

[Time 3]
At two weeks after birth, 70 of 72 infants tested negative for SARS-CoV-2, while two had invalid test results; none of the babies had COVID-19 symptoms. The 53 infants that had a one-month telemedicine visit continued to show no signs of the illness.

The American Academy of Pediatrics also announced July 23 that they were updating their guidance on the care of newborns to mothers with COVID-19. The group’s initial recommendations in early April advised a temporary separation between infected mothers and newborns and feeding expressed breastmilk. But that guidance came at a stage of the pandemic when it was clear the virus was very contagious (SN: 4/2/20), but there was little research on infants and COVID-19.

Since then, the organization has reviewed studies and data from the National Registry for Surveillance and Epidemiology of Perinatal COVID-19 Infection. “At least so far, we don’t have any evidence that babies are getting the virus from the mother after birth and showing up at the hospital horribly sick,” says Karen Puopolo, a neonatologist at the University of Pennsylvania Perelman School of Medicine. Puopolo is the lead author of AAP’s guidance, which now states that a baby is at low risk of infection when staying with the mother after delivery if she wears a mask and cleans hands before holding her infant.

“For whatever reason, this virus is either not as contagious to newborns as it is in other settings or it’s just not as impactful,” she says. “That’s great.”
[248 words]

Source: Science News
https://www.sciencenews.org/article/coronavirus-covid-19-moms-babies-breastfeeding-nursing-masks



The star cluster closest to Earth is in its death throes
By Ken Croswell | JULY 24, 2020 AT 8:00 AM

[Time 4]
The closest cluster of stars to Earth is falling apart and will soon die, astronomers say.

Using the Gaia spacecraft to measure velocities of stars in the Hyades cluster and those escaping from it, researchers have predicted the cluster’s demise. “We find that there’s only something like 30 million years left for the cluster to lose its mass completely,” says Semyeong Oh, an astronomer at the University of Cambridge.

“Compared to the Hyades’ age, that’s very short,” she says. The star cluster, just 150 light-years away and visible to the naked eye in the constellation Taurus, formed about 680 million years ago from a large cloud of gas and dust in the Milky Way.

Stellar gatherings such as the Hyades, known as open star clusters, are born with hundreds or thousands of stars that are held close to one another by their mutual gravitational pull. But numerous forces try to tear them apart: Supernova explosions from the most massive stars eject material that had been binding the cluster together; large clouds of gas pass near the cluster and yank stars out of it; the stars themselves interact with one another and jettison the least massive ones; and the gravitational pull of the whole Milky Way galaxy lures stars away too. As a result, open star clusters rarely reach their billionth birthday.
[222 words]

[Time 5]
The Hyades has survived longer than many of its peers. But astronomers first saw signs of trouble there in 2018, when teams in Germany and Austria independently used the European Space Agency’s Gaia space observatory to find numerous stars that had escaped the cluster. These departing stars form two long tails on opposite sides of the Hyades — the first ever seen near an open star cluster. Each stellar tail stretches hundreds of light-years and dwarfs the cluster itself, which is about 65 light-years across.

In the new work, posted July 6 at arXiv.org, Oh and Cambridge colleague N. Wyn Evans analyzed how the cluster has lost stars over its life. It was born with about 1,200 solar masses but now has only 300 solar masses left. In fact, the two tails of escapees possess more stars than does the cluster. And the more stars the cluster loses, the less gravity it has to hold on to its remaining members, which leads to the escape of additional stars, exacerbating the cluster’s predicament.
[171 words]

[Time 6]
Siegfried Röser, an astronomer at Heidelberg University in Germany who led one of the two teams that discovered the cluster’s tails, agrees that the Hyades is in its sunset years. But he worries that it’s too early to pin a precise date on the funeral. “That seems to be a little bit risky to say,” Röser says. Running a computer simulation with the stars’ masses, positions and velocities should better show what will happen in the future, he says.

The main culprit behind the cluster’s coming demise, Oh says, is the Milky Way. Just as the moon causes tides on Earth, lifting the seas on both the side facing the moon and the side facing away, so the galaxy exerts tides on the Hyades: The Milky Way pulls stars out of the side of the cluster that faces the galactic center as well as the cluster’s far side.

Even millions of years after the cluster disintegrates, its stars will continue to drift through space with similar positions and velocities, like parachutists jumping out of the same airplane. “It’s still probably going to be detectable as a coherent structure in position-velocity space,” Oh says, but the stars will be so spread out from one another that they will no longer constitute a star cluster.
[213 words]

Source: Science News
https://www.sciencenews.org/article/hyades-star-cluster-closest-earth-death-throes

Part III: Obstacle



Vikings had smallpox and may have helped spread the world's deadliest virus
July 23, 2020 | St John's College, University of Cambridge

[Paraphrase 7]
Scientists have discovered extinct strains of smallpox in the teeth of Viking skeletons -- proving for the first time that the killer disease plagued humanity for at least 1400 years.

Smallpox spread from person to person via infectious droplets, killed around a third of sufferers and left another third permanently scarred or blind. Around 300 million people died from it in the 20th century alone before it was officially eradicated in 1980 through a global vaccination effort -- the first human disease to be wiped out.

Now an international team of scientists have sequenced the genomes of newly discovered strains of the virus after it was extracted from the teeth of Viking skeletons from sites across northern Europe. The findings have been published in Science today (July 23, 2020).

Professor Eske Willerslev, of St John's College, University of Cambridge, and director of The Lundbeck Foundation GeoGenetics Centre, University of Copenhagen, led the study.

He said: "We discovered new strains of smallpox in the teeth of Viking skeletons and found their genetic structure is different to the modern smallpox virus eradicated in the 20th century. We already knew Vikings were moving around Europe and beyond, and we now know they had smallpox. People travelling around the world quickly spread Covid-19 and it is likely Vikings spread smallpox. Just back then, they travelled by ship rather than by plane.

"The 1400-year-old genetic information extracted from these skeletons is hugely significant because it teaches us about the evolutionary history of the variola virus that caused smallpox."

Smallpox was eradicated throughout most of Europe and the United States by the beginning of the 20th century but remained endemic throughout Africa, Asia, and South America. The World Health Organisation launched an eradication programme in 1967 that included contact tracing and mass communication campaigns -- all public health techniques that countries have been using to control today's coronavirus pandemic. But it was the global roll out of a vaccine that ultimately enabled scientists to stop smallpox in its tracks.

Historians believe smallpox may have existed since 10,000 BC but until now there was no scientific proof that the virus was present before the 17th century. It is not known how it first infected humans but, like Covid-19, it is believed to have come from animals.

Professor Martin Sikora, one of the senior authors leading the study, from the Centre for GeoGenetics, University of Copenhagen, said: "The timeline of the emergence of smallpox has always been unclear but by sequencing the earliest-known strain of the killer virus, we have proved for the first time that smallpox existed during the Viking Age.

"While we don't know for sure if these strains of smallpox were fatal and caused the death of the Vikings we sampled, they certainly died with smallpox in their bloodstream for us to be able to detect it up to 1400 years later. It is also highly probable there were epidemics earlier than our findings that scientists have yet to discover DNA evidence of."

The team of researchers found smallpox -- caused by the variola virus -- in 11 Viking-era burial sites in Denmark, Norway, Russia, and the UK. They also found it in multiple human remains from Öland, an island off the east coast of Sweden with a long history of trade. The team were able to reconstruct near-complete variola virus genomes for four of the samples.

Dr Lasse Vinner, one of the first authors and a virologist from The Lundbeck Foundation GeoGenetics Centre, said: "Understanding the genetic structure of this virus will potentially help virologists understand the evolution of this and other viruses and add to the bank of knowledge that helps scientists fight emerging viral diseases.

"The early version of smallpox was genetically closer in the pox family tree to animal poxviruses such as camelpox and taterapox, from gerbils. It does not exactly resemble modern smallpox which show that virus evolved. We don't know how the disease manifested itself in the Viking Age -- it may have been different from those of the virulent modern strain which killed and disfigured hundreds of millions."

Dr Terry Jones, one of the senior authors leading the study, a computational biologist based at the Institute of Virology at Charité -- Universitätsmedizin Berlin and the Centre for Pathogen Evolution at the University of Cambridge, said: "There are many mysteries around poxviruses. To find smallpox so genetically different in Vikings is truly remarkable. No one expected that these smallpox strains existed. It has long been believed that smallpox was in Western and Southern Europe regularly by 600 AD, around the beginning of our samples.

"We have proved that smallpox was also widespread in Northern Europe. Returning crusaders or other later events have been thought to have first brought smallpox to Europe, but such theories cannot be correct. While written accounts of disease are often ambiguous, our findings push the date of the confirmed existence of smallpox back by a thousand years."

Dr Barbara Mühlemann, one of the first authors and a computational biologist, took part in the research during her PhD at the Centre for Pathogen Evolution at the University of Cambridge, and is now also based at the Institute of Virology at Charité, said: "The ancient strains of smallpox have a very different pattern of active and inactive genes compared to the modern virus. There are multiple ways viruses may diverge and mutate into milder or more dangerous strains. This is a significant insight into the steps the variola virus took in the course of its evolution."

Dr Jones added: "Knowledge from the past can protect us in the present. When an animal or plant goes extinct, it isn't coming back. But mutations can re-occur or revert and viruses can mutate or spill over from the animal reservoir so there will always be another zoonosis."

Zoonosis refers to an infectious disease outbreak caused by a pathogen jumping from a non-human animal to a human.

The research is part of a long-term project sequencing 5000 ancient human genomes and their associated pathogens made possible thanks to a scientific collaboration between The Lundbeck Foundation, The Wellcome Trust, The Nordic Foundation, and Illumina Inc.

Professor Willerslev concluded: "Smallpox was eradicated but another strain could spill over from the animal reservoir tomorrow. What we know in 2020 about viruses and pathogens that affect humans today, is just a small snapshot of what has plagued humans historically."
[1064 words]

Source: Science Daily
https://www.sciencedaily.com/releases/2020/07/200723143733.htm

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发表于 2020-7-28 21:17:06 | 显示全部楼层
T2  1'53
T3  2’17
T4  2’21
T5  1’48
发表于 2020-7-28 22:39:13 | 显示全部楼层
OBSTACLE:10.16
维京人有天花,有可能已经帮助世界上最致命的病毒传播
科学家已经在维京人骨骼的牙齿部分发现了灭绝的天花菌株。介绍了20世纪天花的一些情况。现在国际科学家已经排列了新发现菌株的基因组。负责这项研究的EW说,这些发现的菌株和现代的天花菌株不同,维京人传播天花的方式和新冠相似。介绍了天花被消灭的过程。历史学家相信天花在10.000BC就存在了,通过给已知最早菌株排序,科学家得出天花存在于维京时代。科学家不知道这些菌株是否致命,但分析出在这些发现之前很可能有更早的病毒,研究小组在给各地的V病毒排序。DLV说理解这种病毒的基因组成对现在产生的病毒疾病有帮助。介绍了最早版本的天花。DTJ,DBM,DJ都强调了这项研究的重要性。这项研究推翻了一个理论。最后作者感谢了一些机构的协作,总结天花虽然小时,但新病毒可能明天就产生,2020年人们知道的病毒感染人类的知识只是病毒感染人类的历史快照。
发表于 2020-7-29 01:00:06 发自 iPhone | 显示全部楼层
OB:8’44[1064W]
发表于 2020-7-30 22:13:29 | 显示全部楼层
OB:
12:44
发表于 2020-7-31 10:39:57 | 显示全部楼层
# 2849
Speak
Advances - Quick hits
Survived lizard,18 months later, large size confirm the data hurricane data.
1.9 million per square meter, sea pollution
Frog island, chili and andis human condition
Iraq, causing death 1888,
Japan,underground,tons of water.  
Kenya, scientist identified mosquito, fugues, disease carry paradise.

Time2 [227 words] 1:19
Mother confirmed positive covid19 can breast-feeding their babies and not make them infected by the virus.
Time3 [248 words] 1:13
It was suggest to separate the mom and newborn babies in April when it is not clear the virus was very contagious.
The updated research shows that the virus is either not as contagious to newborns or it’s just not as impactful.
Time4 [222 words] 1:41
The closest cluster of stars to earth is falling apart and will be dead in 80 million years.
Time5 [171 words] 1:14
The falling apart was first identified by the scientist in Germany in 2018. The solar mess was about 1200 and now only 300 left. The more the stars lost the less gravity the cluster will have to keep the rest of the members.
Time6 [213 words] 1:40
Part III: Obstacle [ words]
China Tries Its Favorite Economic Cure: More Construction
New words:

单词        解释                单词        解释
Eradicated        消除                Plow        生产犁
On its face        从表面来看                Inextricably        解不开,纠缠不清的
Rebound        复苏, 反弹                Entwined        缠住,盘绕
Downturn         衰退                Shift gear        改变策略
Glamorous         光彩夺目的                Pivotal        关键的
Prosper        繁荣                Tame        制服, 控制
Crane and bulldozer        起重机和推土机                Scant        不足
Cusp        尖端                Archrival        主要竞争对手
Overhaul        大修,改革,检查                Unrelenting        持续不断的
Throng        挤满                Desert        放弃,遗弃
Labyrinth        迷宫                Utensil        炊具
Stall        摊位                       
                               
                               
                               


发表于 2020-7-31 11:40:44 | 显示全部楼层
Masks help new moms with COVID-19 safely breastfeed their babies
[Time2]1’54
If Mothers with COVID-19 make a considerate safety precautions like wearing a surgical mask, they will not infect the virus to their babies when they breastfeed them.
[Time3]1’56
The paragraph focuses on how researchers get this conclusion. Researchers found that no infants show signs of COVID-19 after tracing them for a period of time. In sum, this piece of news is good to us.

Breastfeed: when a mother breast-feeds her baby, she feeds it with milk directly from her breasts rather than with artificial or cow’s milk from a bottle
Dooning: wear  dooning a mask
发表于 2020-7-31 12:52:38 | 显示全部楼层
T2 1'25
T3 1'21

A research in the U.S has found out that by taking effective infection-control measures (e.g. wearing a surgical mask), mothers who are tested positive for Covid-19 can still breastfeed new-born babies without getting the babies infected. Besides, it mentions that early skin-to-skin touch and breastfeeding has other benefits.

T4 1'48
T5 1'03
T6 1'04
发表于 2020-7-31 22:11:54 | 显示全部楼层
T2 1'21''
T3 1'19''
T4 1'08''
T5 52''
T6 1'09''
T7 5'21''
发表于 2020-8-1 13:07:14 | 显示全部楼层
OB 7'53

A recent study has found a piece of evidence that smallpox, a kind of virus that killed over 300 million people and was ultimately eradicated through a global vaccination last century, already existed at least 1400 years ago. A group of scientists extracted smallpox from the teeth skeleton from Viking people, and they also compared it with the smallpox appeared in the 20th century. The genetic difference has been noticed. It is still unknown how the virus survived in the Viking age, However, knowing the process of evolution can help people fight against fatal virus in the future.
saif
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