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試題分類：
口語
練習(xí)次數(shù)：1次
Rogue theory of smell gets a boost
1.A controversial theory of how we smell, which claims that our fine sense of
odour depends on quantum mechanics, has been given the thumbs up by a team of
physicists.
2.Calculations by researchers at University College London (UCL) show that
the idea that we smell odour molecules by sensing their molecular vibrations
makes sense in terms of the physics involved.
3.That's still some way from proving that the theory, proposed in the
mid-1990s by biophysicist Luca Turin, is correct.But it should make other
scientists take the idea more seriously.
4."This is a big step forward," says Turin, who has now set up his own
perfume company Flexitral in Virginia.He says that since he published his
theory, "it has been ignored rather than criticized."
5.Most scientists have assumed that our sense of smell depends on receptors
in the nose detecting the shape of incoming molecules, which triggers a signal
to the brain.This molecular 'lock and key' process is thought to lie behind a
wide range of the body's detection systems: it is how some parts of the immune
system recognise invaders, for example, and how the tongue recognizes some
tastes.
6.But Turin argued that smell doesn't seem to fit this picture very
well.Molecules that look almost identical can smell very different — such as
alcohols, which smell like spirits, and thiols, which smell like rotten eggs.And
molecules with very different structures can smell similar.Most strikingly, some
molecules can smell different — to animals, if not necessarily to humans —
simply because they contain different isotopes (atoms that are chemically
identical but have a different mass).
7.Turin's explanation for these smelly facts invokes the idea that the smell
signal in olfactory receptor proteins is triggered not by an odour molecule's
shape, but by its vibrations, which can enourage an electron to jump between two
parts of the receptor in a quantum-mechanical process called tunnelling.This
electron movement could initiate the smell signal being sent to the brain.
8.This would explain why isotopes can smell different: their vibration
frequencies are changed if the atoms are heavier.Turin's mechanism, says
Marshall Stoneham of the UCL team, is more like swipe-card identification than a
key fitting a lock.
9.Vibration-assisted electron tunnelling can undoubtedly occur — it is used
in an experimental technique for measuring molecular vibrations."The question is
whether this is possible in the nose," says Stoneham's colleague, Andrew
Horsfield.
10.Stoneham says that when he first heard about Turin's idea, while Turin was
himself based at UCL, "I didn't believe it".But, he adds, "because it was an
interesting idea, I thought I should prove it couldn't work.I did some simple
calculations, and only then began to feel Luca could be right." Now Stoneham and
his co-workers have done the job more thoroughly, in a paper soon to be
published in Physical Review Letters.
11.The UCL team calculated the rates of electron hopping in a nose receptor
that has an odorant molecule bound to it.This rate depends on various properties
of the biomolecular system that are not known, but the researchers could
estimate these parameters based on typical values for molecules of this
sort.
12.The key issue is whether the hopping rate with the odorant in place is
significantly greater than that without it.The calculations show that it is —
which means that odour identification in this way seems theoretically
possible.
13.But Horsfield stresses that that's different from a proof of Turin's
idea."So far things look plausible, but we need proper experimental
verification.We're beginning to think about what experiments could be
performed."
14.Meanwhile, Turin is pressing ahead with his hypothesis."At Flexitral we
have been designing odorants exclusively on the basis of their computed
vibrations," he says."Our success rate at odorant discovery is two orders of
magnitude better than the competition." At the very least, he is putting his
money where his nose is.
Questions 5-9
Complete the sentences below with words from the passage.Use NO MORE THAN
THREE WORDS for each answer.
5.The hypothesis that we smell by sensing the molecular vibration was made by
______.
6.Turin's company is based in ______.
7.Most scientists believed that our nose works in the same way as our
______.
8.Different isotopes can smell different when ______ weigh differently.
9.According to Audrew Horsfield, it is still to be proved that ______ could
really occur in human nose.
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高級統(tǒng)計師
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Selling Digital Music without Copy-protection Makes Sense
A. It was uncharacteristically low-key for the industry’s greatest showman.
But the essay published this week by Steve Jobs, the boss of Apple, on his
firm’s website under the unassuming title “Thoughts on Music” has nonetheless
provoked a vigorous debate about the future of digital music, which Apple
dominates with its iPod music-player and iTunes music-store. At issue is
“digital rights management” (DRM)—the technology guarding downloaded music
against theft. Since there is no common standard for DRM, it also has the
side-effect that songs purchased for one type of music-player may not work on
another. Apple’s DRM system, called FairPlay, is the most widespread. So it came
as a surprise when Mr. Jobs called for DRM for digital music to be
abolished.
B. This is a change of tack for Apple. It has come under fire from European
regulators who claim that its refusal to license FairPlay to other firms has
“l(fā)ocked in” customers. Since music from the iTunes store cannot be played on
non-iPod music-players (at least not without a lot of fiddling), any iTunes
buyer will be deterred from switching to a device made by a rival firm, such as
Sony or Microsoft. When French lawmakers drafted a bill last year compelling
Apple to open up FairPlay to rivals, the company warned of “state-sponsored
piracy”. Only DRM, it implied, could keep the pirates at bay.
C. This week Mr. Jobs gave another explanation for his former defence of DRM:
the record companies made him do it. They would make their music available to
the iTunes store only if Apple agreed to protect it using DRM. They can still
withdraw their catalogues if the DRM system is compromised. Apple cannot license
FairPlay to others, says Mr Jobs, because it would depend on them to produce
security fixes promptly. All DRM does is restrict consumer choice and provide a
barrier to entry, says Mr Jobs; without it there would be far more stores and
players, and far more innovation. So, he suggests, why not do away with DRM and
sell music unprotected? “This is clearly the best alternative for consumers,” he
declares, “and Apple would embrace it in a heartbeat.”
D. Why the sudden change of heart? Mr Jobs seems chiefly concerned with
getting Europe’s regulators off his back. Rather than complaining to Apple about
its use of DRM, he suggests, “those unhappy with the current situation should
redirect their energies towards persuading the music companies to sell their
music DRM-free.” Two and a half of the four big record companies, he helpfully
points out, are European-owned. Mr Jobs also hopes to paint himself as a
consumer champion. Apple resents accusations that it has become the Microsoft of
digital music.
E. Apple can afford to embrace open competition in music players and online
stores. Consumers would gravitate to the best player and the best store, and at
the moment that still means Apple’s. Mr Jobs is evidently unfazed by rivals to
the iPod. Since only 3% of the music in a typical iTunes library is protected,
most of it can already be used on other players today, he notes. (And even the
protected tracks can be burned onto a CD and then re-ripped.) So Apple’s
dominance evidently depends far more on branding and ease of use than
DRM-related “l(fā)ock in”.
F. The music giants are trying DRM-free downloads. Lots of smaller labels
already sell music that way. Having seen which way the wind is blowing, Mr Jobs
now wants to be seen not as DRM’s defender, but as a consumer champion who
helped in its downfall. Wouldn’t it lead to a surge in piracy? No, because most
music is still sold unprotected on CDs, people wishing to steal music already
can do so. Indeed, scrapping DRM would probably increase online-music sales by
reducing confusion and incompatibility. With the leading online store, Apple
would benefit most. Mr Jobs’s argument, in short, is transparently self-serving.
It also happens to be right.
Notes to Reading Passage 1
1. low-key:
抑制的，受約束的，屈服的
2. showman:
開展覽會的人, 出風(fēng)頭的人物
3. unassuming:
謙遜的, 不夸耀的, 不裝腔作勢的
4. iPod：
(蘋果公司出產(chǎn)的)音樂播放器
5. iTunes store：
(蘋果公司出產(chǎn)的)在線音樂商店
6. get off person’s back:
不再找某人的麻煩，擺脫某人的糾纏
7. gravitate:
受吸引，傾向于
8. unfazed:
不再擔(dān)憂，不被打擾
Questions 1-7
Do the following statemets reflect the claims of the writer in Reading
Passage 1?
Write your answer in Boxes 1-7 on your answer sheet.
TRUE if the statement reflets the claims of the writer
FALSE if the statement contradicts the claims of the writer
NOT GIVEN if it is impossbile to say what the writer thinks about this
1. Apple enjoys a controlling position in digital music market with its iPod
music-player and iTunes music-store.
2. DRM is a government decree issued with a purpose to protect downloaded
music from theft by consumers.
3. Lack of standardization in DRM makes songs bought for one kind of music
player may not function on another.
4. Apple has been criticized by European regulators since it has refused to
grant a license FairPlay to other firms.
5. All music can be easily played on non-iPod music devices from Sony or
Microsoft without too much fiddling.
6. Apple depends far more on DRM rather than branding for its dominance of
the digital music devices.
7. If DRM was cancelled, Sony would certainly dominate the international
digital music market.
Questions 8-10
Choose the appropriate letters A-D and write them in boxes 8-10 on your answe
sheet.
8. Which of the following statements about Mr. Jobs’ idea of DRM is NOT
TRUE?
A. DRM places restrictions on consumer’ choice of digital music products
available.
B. DRM comples iTunes buyers to switch to a device made by Sony or
Microsoft.
C. DRM constitutes a barrier for potential consumers to enter digital music
markets.
D. DRM hinders development of more stores and players and technical
innovation.
9. The word “unfazed” in line 3 of paragraph E, means___________.
A. refused
B. welcomed
C. not bothered
D. not well received
10. Which of the following statements is TRUE if DRM was scapped?
A. Sony would gain the most profit.
B. More customers would be “l(fā)ocked in”.
C. A sudden increase in piracy would occur.
D. Online-music sales would probably decrease.
Questions 11-14
Complete the notes below.
Choose NO MORE THAN THREE WORDS from Reading Passage 1 for each answer.
Write your answers in boxes 11-14 on your answer sheet.
Mr. Steve Jobs, the boss of Apple, explains the reason why he used to defend
DRM, saying that the company was forced to do so: the record companies would
make their music accessible to …11...only if they agreed to protect it using
DRM; they can still…12…if the DRM system is compromised. He also provides the
reason why Apple did not license FairPlay to others: the company relies on them
to …13….But now he changes his mind with a possible expectation that Europe’s
regulators would not trouble him any more in the future. He proposes that those
who are unsatisfactory with the current situation in digital music market should
…14… towards persuade the music companies to sell their music DRM-free.
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