【每日阅读训练第四期——速度越障18系列】【18-06】科技

zxppx

号外！！大家久候了，17系列的出勤统计终于出来啦，快来看看自己上系列的表现如何吧！ 点击这里~

大家好，胖胖翔来啦！因为感觉可能读完文章之后就忘记去看隐藏的标题了，所以这次没有隐藏标题，希望能够帮助大家理解文章。第三和第四篇来自一篇文章，enjoy~

Part I: Speed

[Time 1]

Article 1

Life After Extinction

Mass extinctions have a silver lining, providing opportunities for marginalized creatures to rise to power. While that notion seems obvious, it hadn't been demonstrated for the end-Permian extinctions, which occurred about 252 million years ago and wiped out about 90% of life on Earth. So, researchers took a detailed look at the numbers and distribution of land-dwelling species at five sites scattered across the southern part of Pangaea, the supercontinent that existed at the time of the die-offs. (Previous analyses had looked at only trends in marine species or for limited regions on land, the team notes.) Of the 62 species found at the sites about 5 million years before the die-offs, 21 (or about 34%) were found in two or more of the sites, suggesting a wide distribution of those creatures. But 10 million years after the end-Permian extinctions, only five species out of 68—none of which matched the 62 that lived before the die-offs—were found at more than one site. The analysis also reveals that after the mass extinctions, species typically had smaller, less-connected geographical ranges than did the species living before the die-offs, the researchers report online today in the Proceedings of the National Academy of Sciences. Altogether, the trends suggest that when widely prevalent creatures such as the pig-sized Dicynodon (left) were removed from the scene, species such as the 3-meter-long Asilisaurus (right)—a member of the archosaurs, which included dinosaurs and many groups alive today, such as crocodilians and birds—could diversify and thrive.

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[Time 2]

Article 2

Stop Cleaning Inside Your Ears: It’s Bad for You
Everyone always says you should wash behind your ears. But what about inside your ears? You should pretty much never clean those, and trying sends more people to the hospital every year with cotton swab–induced injuries than show up with wounds from razor blades, according to Real Clear Science. Here’s the basic problem:

For the most part, swabs merely condense and impact the earwax further into the ear canal, where it can cause pain, pressure, and temporarily poor hearing.

“There’s no need to clean your ears with a cotton bud,” writes Dr. Rob Hicks. “The ear has its own internal cleaning mechanism. Fats and oils in the ear canal trap any particles and transport them out of the ear as wax. This falls out of the ear without us noticing.”

Besides, ear wax isn’t dirt. It’s supposed to be there, says the American Hearing Research Association:

First, one should realize that wax isn’t all that bad. It keeps your ear dry and helps prevent infection. Thus, you don’t want to eliminate wax; you want to keep it from blocking your ears.

The Telegraph says:

“In most circumstances, wax is actually beneficial to the ear,” says Simon Baer, a consultant ear, nose and throat surgeon at the Conquest Hospital in Hastings. “It causes foreign bodies to adhere to it, preventing them from going further into the ear, and it has anti-bacterial properties. Removing it is like taking the wax off the surface of polished wooden furniture. It makes the delicate underlying skin of the ear more susceptible to infection.”

Of course, some people have way too much earwax, but that’s rare. Certainly not common enough to support the huge earwax removal industry. The Wall Street Journal writes:

Some 12 million Americans visit medical professionals annually for earwax removal. Millions more have it done at spas and ear-candling parlors, which theoretically suck out earwax with a lighted candle. North Americans also spent $63 million last year on home ear-cleaning products, from drops to irrigation kits, according to market research firm Euromonitor International.

Removing wax yourself can be dangerous, though. Thousands of people go to the hospital every year because of those pesky cotton swabs. So not only is it doing nothing for you, it’s actually perhaps hurting.

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[Time 3]

Article 3

Protein gets in on DNA's origami act

Engineered bacteria make self-assembling tetrahedra.

Practitioners of DNA origami have spent the better part of the past decade folding the molecule into minuscule smiley faces, boxes, letters of the alphabet and dozens of other intricate shapes.

Proteins, on the other hand, have been rather late in joining the origami party — even though nature is adept at moulding them into a dazzling array of functional shapes, including molecular-recognition systems and catalysts.

Now Roman Jerala, a biochemist at the National Institute of Chemistry in Ljubljana, Slovenia, is making up for lost time. He and his colleagues have designed and built a protein that folds itself into a tetrahedron — a pyramid with a triangular base — and he says that the strategy could be used to make a wide range of other shapes. Whereas examples of DNA origami often look pretty, few of these creations have any practical use. Proteins, on the other hand, are much better suited to performing useful tasks, such as delivering drugs, according to Jerala.

Doing the twist

Proteins are long chains of amino acids folded into complicated shapes, and the precise sequence of these building blocks determines the overall structure of the folded molecule. One common structural element in proteins is the coiled coil, in which two or more helices of amino acids twist around each other like the strands of a rope. The helices stick together with the help of a mutual attraction between water-repelling (hydrophobic) amino acids, which run up the inside of the coiled coil.

Jerala reasoned that six coiled coils could be used as the edges of a tetrahedron. So his team worked out the amino-acid sequences of 12 different protein helices that each had unique patterns of hydrophobic regions along their length. This fingerprint ensured that each helix could pair with only one of the others in the set.

[字数：305]

[Time 4]

Then the researchers joined the 12 helices into a chain, using flexible linkers of four amino acids to act like a hinge between each helix. Genetically modified Escherichia coli bacteria were drafted in to synthesize the protein, which — once purified — folded into tetrahedra measuring just 5 nanometres along each edge (see image above). “It’s a new protein fold that doesn’t exist in nature,” says Jerala. The work is published today in Nature Chemical Biology1.

"This type of assembly has been achieved before using DNA, but it has always been assumed that it would be much harder to do this with proteins because there is no straightforward code that relates sequence to structure, as there is with DNA,” says Dek Woolfson, a biochemist at the University of Bristol, UK.

Woolfson and his colleagues have recently joined coiled coils coming from distinct protein chains to build protein ‘cages’2, but he says that stringing all the components of the coiled coils into a single protein chain, as Jerala has done, is an exciting step because it offers a way to design and produce completely new protein shapes using reprogrammed bacteria.

Jerala says that attaching antibodies to the four vertices of his protein tetrahedron could enable it to target particular cells. Any drugs loaded inside could be released by breaking the tetrahedron apart — by means of a competing protein, a change in pH or a pulse of light hitting a photosensitive linker, he suggests.

Creating such a working system will take many years. For now, Jerala’s team is trying to double the size of the coiled coils in the tetrahedron, and thinking about making other shapes, such as prisms and bipyramids.

[字数：277]

[Time 5]

Article 4

China earthquake points to future risk sites

But researchers at odds over effects of Ya'an tremor on nearby seismic faults.

The deadly tremor that shook the city of Ya'an in southwestern China last weekend may hint at where future quakes will strike in the region, researchers say. But they disagree on which seismic fault is likely to rupture next.

At 8:02 a.m. local time on 20 April, an earthquake recorded as magnitude 6.6 by the US Geological Survey struck Ya’an in Sichuan province. According to the latest official figures, the death toll has reached 193, with 12,211 people injured and 25 missing

The Ya’an quake was caused by the failure of the southern segment of the Longmenshan fault. In May 2008, a rupture at the northern end of the same fault caused the devastating magnitude-7.9 Wenchuan earthquake that killed around 80,000 people.

The latest quake “is not surprising”, says Liu Qiyuan, a geophysicist at the China Earthquake Administration’s Institute of Geology in Beijing. In the aftermath of the Wenchuan quake, several research groups, including Liu’s, calculated the stress changes in adjacent faults and found that the biggest stress increase was in the southern Longmenshan fault.  

“As the stress has been released by the Ya’an quake, the fault is now safe,” says Liu. He predicts that the Xianshuihe and Anninghe faults — which intersect with the southern end of the Longmenshan fault from the west and east, respectively — now pose the greatest seismic hazards.

Both of those faults are very active and have produced several large earthquakes over the past 200 years. Moreover, the Wenchuan quake and the magnitude-6.9 Yushu quake in 2010have added considerable stress in faults, says Liu. With a network of about 300 broadband seismometers in the region, “we are monitoring the crust movement very closely,” he says.

Stresses and strains

However, Mian Liu, a geophysicist at the University of Missouri in Columbia, does not agree. “The kind of stress increase caused by an adjacent fault failure is typically less than a few per cent of the stress that is required to produce a large earthquake,” he says. “It’s not a reliable indicator for seismic hazards.”

By contrast, he adds, analyses of a fault’s seismic moment — a measure of strain energy in the crust that could be used to produce earthquakes — are more useful. “It’s like checking the bank balance by calculating the incomes and the spendings,” Mian Liu says.   

The ‘incomes’ depend on how fast the fault moves, which indicates how quickly the strain energy builds up over time. The ‘spendings’ are based on the history of previous ruptures. Such accounting led Mian Liu and his colleagues to predict in 2010 that the southern segment of the Longmenshan fault could rupture and produce quakes of magnitude 7.7 in the next 50 years1. In the event, it took only 3 years. “It seems that nature is in a hurry,” he says.

“This doesn’t mean that the Longmenshan fault is now safe,” says Mian Liu. Based on seismic measurements, he notes that last week's quake in Ya'an didn’t rupture the entire southern segment, but instead released only one-third of its accumulated energy. “The 60-kilometre intact stretch between the Ya’an and Wenchuan quakes is likely to rupture in the next few decades,” he says. “It’s still able to cause earthquakes of magnitude 6 to 7.”

By comparison, Mian Liu thinks that the Xianshuihe and Anninghe faults are less risky because, although the crust movement has generated a lot of strain energy, they have ‘spent’ a lot in the past, he says.

[字数：592]

Part II: Obstacle

Article 5

World's Longest-Running Plant Monitoring Program Now Digitized

Researchers at the University of Arizona's Tumamoc Hill have digitized 106 years of growth data on individual plants, making the information available for study by people all over the world. Knowing how plants respond to changing conditions over many decades provides new insights into how ecosystems behave.
The permanent research plots on Tumamoc Hill represent the world's longest-running study that monitors individual plants, said co-author Larry Venable, director of research at Tumamoc Hill. Some of the plots date from 1906 -- and the birth, growth and death of the individual plants on those plots have been periodically recorded ever since.

The century-long searchable archive is unique and invaluable, said Venable, a UA professor of ecology and evolutionary biology who has been studying plants on Tumamoc since 1982. "You can see the ebb and flow of climate, and you can see the ebb and flow of vegetation," he said. Lead author Susana Rodriguez-Buritica said, "Long-term data sets have a special place in ecology." The records have allowed scientists to estimate life spans for desert perennials, some of which are very long-lived, Venable said.

In addition, data from the plots on Tumamoc Hill reveal changes in the Sonoran Desert and have been important to key advances in the science of ecology. For example, the Tumamoc plant censuses helped overturn the long-standing idea that plant communities progress through a series of steps to a stable collection of species known as a climax community. "The desert wasn't progressing toward a climax community," he said. Instead of being in synch, each species and plot was changing to its own rhythm.

Rodriguez-Buritica, a postdoctoral research associate in the UA department of ecology and evolutionary biology, Venable and their co-authors Helen Raichle and Robert H. Webb of the U.S. Geological Survey and Raymond M. Turner, formerly of USGS, have published a description of their data in the Ecological Society of America's journal Ecology and archived the data set with the society athttp://www.esapubs.org/archive/ecol/E094/083/.

The title of their paper is, "One hundred and six years of population and community dynamics of Sonoran Desert Laboratory perennials." The National Science Foundation, the USGS and the U.S. National Park Service funded the archiving.

Landmark research on the physiology and ecology of desert plants has been conducted on Tumamoc Hill ever since the Carnegie Institution of Washington established the Desert Laboratory there in 1903 to study how plants cope with living in the desert.

The first permanent plots, generally 33 feet by 33 feet (10 meters by 10 meters), were established in 1906 by Volney Spalding; nine of his original plots remain to this day. Additional plots were established by Forrest Shreve in the 1910s and 1920s. Two more plots were added in 2010. Currently, there are 21 plots.

For every perennial plant within each plot, the ecologists recorded the species, the area the plant covered and its location. Even seedlings were identified and mapped. In addition to the written records, repeated photographs of the plots have been taken since 1906. Those photographs are in the Desert Laboratory Collection of Repeat Photography at the USGS in Tucson, Ariz.

Over the years, botanists and ecologists have helped census and re-census the plots. Co-author Turner took over the work when he came to the UA as a botany professor in 1957, continued while a botanist for USGS and continues to do in retirement. In 1993, co-author Webb took up the project and is keeping the censuses going.

Sorting through data recorded from 2012 back to 1906 was a huge challenge, said Rodriguez-Buritica. She had something to build on: Janice Bowers of USGS had begun to archive the records but retired before finishing. Initially, Rodriguez-Buritica and Venable thought a year would do it -- but the task ended up taking much longer. The records were in several places -- some at the library or in storage at Tumamoc and some in the UA library's Special Collections. One of the challenges Rodriguez-Buritica faced is that methods of collecting and recording information about plants have changed over time.

Spalding, who established the very first plots in 1906, worked long before the age of computers -- he recorded his observations in a small notebook. Ecologists continued to record their field observations in paper notebooks and created maps on graph paper well into the latter part of the 20th century.

All those paper records had to be digitized.

Only in the last 20 years have scientists been pinpointing plant locations and other observations directly onto a map within their computers by using GPS and GIS technology.

Upon reviewing and checking the data, Rodriguez-Buritica realized that she needed to standardize the information collected over a century so that other scientists could analyze it. Her expertise in applied statistics and spatial ecology was perfect for the job. She also computerized the series of maps created over time so new investigators could see all the plant location maps created since 1906. By putting all the information into a standardized digital format and making it easily accessible on the Web, Rodriguez-Buritica, Venable and their colleagues have ensured that other researchers can build on and expand this unique data set. Tumamoc Hill is one of the birthplaces of plant ecology, Venable said. "In the first half of the 20th century, all the great plant ecologists either worked here or came though here," he said. "Plant ecologists from the Desert Lab were key in founding the Ecological Society of America and its flagship journal, Ecology. It is satisfying to see the project come full circle and be permanently archived 100 years later by the journal that these researchers started."

The Desert Lab and Tumamoc Hill have been designated as a National Environmental Study Site, a National Historic Landmark, an Arizona State Scientific and Educational Natural Area and are on the National Register of Historic Places.

[字数：969]

zxppx

1.
1-34
2.
2-17
3.
1-49
4.
1-27
5.
3-34
6.
4-55

杀G给猴看

今天的还没看又来占座TT好惭愧TT

1 A 01:43
2 A 02:15
3 A 01:42
4 A 01:28
5 A 03:15

晓野的野

辛苦了胖胖翔，过来占座位。
--------------------------------------------------------------------------------------------------------------------------------------------------
1:31
Researchers took a detailed look at the distincted species.
2:00
Introduce the reasons why people should not clean inside their ears.
1:53
1:32
It talks about researches on proteins.
3:15
It talk about the earthquake in China.Researches discuss about the appearence of the earthquake
5:05 obstalce
MI: Researches spend a lot of time and efforts collecting the data on plants, and now the data is digitized.
Structure:
Data is digitized to make the information avalaible for people.
The data about plants from TH has been periodically recorded.
Long term data is valuable.
Data from the spots on TH can reveal changes in the SD and is very impotant.
Introduce L's research.
The development of the plots.
Researchers gathered to record those data. People try to make those data more detailed and put those data into standardized digital.

过来补交作业，最近半期了，各种作业，各种论文，各种忧桑.....
一段时间能专心做一件事情多好，可是事情总是很多，永远都做不完....
矮油矮油，不要抱怨了！！！！吼，来一件做一件，来两件干一双！！！
写论文去了

beckybei11

谢谢LZ，辛苦了
                       

112

215

Peopledo not need to clean inside of their ear. It is unnecessary to do soas the ear can clean by itself and it is dangerous. The wax issupposed to be there and it is beneficial to human.

5083&4

Proteinjoined the DNA origami party rather late, however, Protein is moreuseful than other DNA origami creations. Proteins are chains of AA,and AA can determine the structure of Molecule. 2-3H of AA made up ofCC, CC is common element of Protein.

Theresearchers jointed 12 helices into a chain and create a new protein.

Cages2 made the production of new protein shapes possible.

435

Earthquakein Ya An may give us a hint of future earthquakes. Some of theresearchers say that the earthquake in Ya An is not suprising to themas they have already forecast the EQ.

Thestress increase in LMS is the reason for the Wen Chuan EQ. Theremaining stree form the LMS  fault is releases in YA EQ and we donot need to worry about the LMS fault. XSH and ANH are more dangerousnow.

Someother researchers do not agree as they state that the stress from thefault is not enough to cause a big EQ. This group of researchersbelieve that the analyzing of S movement may assist us in forecastingthe future EQ. The way to analyzing S movement is similar to thecalculation of income and cost.

521

Researcherin UA has digitalized 106 years data of individual plants and madethe data available to people all around the world. These data willgive researchers more info on how the ecosystem behave.

Thedata provided is unique and invaluable. The data is precious toresearchers who are trying to find the change of climate and the lifespan of some long-lived plants. The data also overturn the long holdnotion of the existing of the chimax community and found out thatplants have their own rhythm to change.

Theresearcher overcame numerous difficulties to record the data and madethe data digitalized. However, all the work is worthy considering thesignificance of the data.

none123

2‘08 after the mass extinction ,the geographical range has declined and less connected.scientists forcast that if some prevalent species died out,a lot of species like birds will thrive .
2'52 earware removal is totally not necessary.on the contrary,it is harmful to our ear's health.
3'03scientists have designed a protein that looks like a pyramid with a triangular base and they said it can be made into other shapes.Jerala reasoned that six coiled coils could be used as the edges of a tetrahedron.,
6'09 a century record of the desert's plants since 1903.it is very useful.how scientusts record the data with the time on and now the digital record make it possible for scientists to analyse the data.
2'13 design and produce completely new protein shapes using reprogrammed bacteria.attach antibodies to the protein tetrahedron could enable it to be used in curing disease
3'40 The Ya’an quake was caused by the failure of the southern segment of the Longmenshan fault. qi yuan  said the quake was not surprising and since the stress has been released,ya'an is safe now.however think the strain energy is more harmful and the quake has only released one-third of the acumulated energy,so there will be earthquakes in the future

abjure

这个速度，太难了。。。
1 dig ear is possilbe hurt your ear.  Wag is useful to human ear, of course too much wag is rarely for people.
Wag have its own mechinal to clean.   US have thousands of people is hurt by clearn ear.

2.  gene can be produced.


5 ya an earthquate,  wen chuan earthquake  all happend in long men shan zone.   It means that recent these area will be safe because the energy has been released.




越障

the oldest plant have 106 years history at USA.
The plant is used to observe the change of desert in Arionza.
The eariest plant has been planted in 1906.  now have 9 set still alive.  the following scienist added some new sets and total now is 22.
Before 1950, all of greatest  scienist came the place .
The noting method is changing over time.  The beginning of last century, the observer use note pad to write down information.
In recent 20 years, observer can use GPS to accurately locate these plants.

zxppx

abjure 发表于 2013-5-1 10:52
这个速度，太难了。。。

第三篇速度是比较难，有很多科学名词，要弄清他们之间的关系比较困难。我主要是想让大家挑战一下这样的文章。其他的速度难度都还一般，第五篇的文字比较多，但是内容不难理解。

ywxkdxh

辛苦LZ啦~
1‘24
2’56
1‘57
1’59
3‘33
5’49

2012Michelle

谢谢胖胖的整理，辛苦了！劳动节快乐！

我也觉得第三篇速度难，看不懂就走神，走神就啥也看不进去，呵呵。

交作业：
Time1 1'30"
New researches found that only small percents of species extincted after the end-Permian extinctions.

Time2 1'47"
It's not necessory to clean ears with cotton bud, our ears have its own internal cleaning mechanism.

Time3 1'54"

Time4 1'14"
看的时候走神，3、4扫完的，汗。

Time5 2'49"
Scientists are trying to explain how the Ya'an earthquake happened, mainly there were two explanations.

Obstacle 4'44"
Main Idea: The information collected from  the current TH has been done for 106 years.
Authur's attitude: Active (+)
Article structure:
1) The TH has collected information from monitoring individual plants for 106 years.
2) Further introduction about the program:
-- data has been published;
-- no result from analysizing the data yet.
-- challenges:
>> too much information for the past 106years.
>> it needs long time to study the data.
3) Conclusion: standardizing the data in a univeral format will be done in future for further studying on the data collected.