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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.
1 There's a dimmer switch inside the sun that causes its brightness to rise
and fall on timescales of around 100,000 years - exactly the same period as
between ice ages on Earth. So says a physicist who has created a computer model
of our star's core.
2 Robert Ehrlich of George Mason University in Fairfax, Virginia, modelled
the effect of temperature fluctuations in the sun's interior. According to the
standard view, the temperature of the sun's core is held constant by the
opposing pressures of gravity and nuclear fusion. However, Ehrlich believed that
slight variations should be possible.
3 He took as his starting point the work of Attila Grandpierre of the Konkoly
Observatory of the Hungarian Academy of Sciences. In 2005, Grandpierre and a
collaborator, Gábor ágoston, calculated that magnetic fields in the sun's core
could produce small instabilities in the solar plasma. These instabilities would
induce localised oscillations in temperature.
4 Ehrlich's model shows that whilst most of these oscillations cancel each
other out, some reinforce one another and become long-lived temperature
variations. The favoured frequencies allow the sun's core temperature to
oscillate around its average temperature of 13.6 million kelvin in cycles
lasting either 100,000 or 41,000 years. Ehrlich says that random interactions
within the sun's magnetic field could flip the fluctuations from one cycle
length to the other.
5 These two timescales are instantly recognisable to anyone familiar with
Earth's ice ages: for the past million years, ice ages have occurred roughly
every 100,000 years. Before that, they occurred roughly every 41,000 years.
6 Most scientists believe that the ice ages are the result of subtle changes
in Earth's orbit, known as the Milankovitch cycles. One such cycle describes the
way Earth's orbit gradually changes shape from a circle to a slight ellipse and
back again roughly every 100,000 years. The theory says this alters the amount
of solar radiation that Earth receives, triggering the ice ages. However, a
persistent problem with this theory has been its inability to explain why the
ice ages changed frequency a million years ago.
7 "In Milankovitch, there is certainly no good idea why the frequency should
change from one to another," says Neil Edwards, a climatologist at the Open
University in Milton Keynes, UK. Nor is the transition problem the only one the
Milankovitch theory faces. Ehrlich and other critics claim that the temperature
variations caused by Milankovitch cycles are simply not big enough to drive ice
ages.
8 However, Edwards believes the small changes in solar heating produced by
Milankovitch cycles are then amplified by feedback mechanisms on Earth. For
example, if sea ice begins to form because of a slight cooling, carbon dioxide
that would otherwise have found its way into the atmosphere as part of the
carbon cycle is locked into the ice. That weakens the greenhouse effect and
Earth grows even colder.
9 According to Edwards, there is no lack of such mechanisms. "If you add
their effects together, there is more than enough feedback to make Milankovitch
work," he says. "The problem now is identifying which mechanisms are at work."
This is why scientists like Edwards are not yet ready to give up on the current
theory. "Milankovitch cycles give us ice ages roughly when we observe them to
happen. We can calculate where we are in the cycle and compare it with
observation," he says. "I can't see any way of testing [Ehrlich's] idea to see
where we are in the temperature oscillation."
10 Ehrlich concedes this. "If there is a way to test this theory on the sun,
I can't think of one that is practical," he says. That's because variation over
41,000 to 100,000 years is too gradual to be observed. However, there may be a
way to test it in other stars: red dwarfs. Their cores are much smaller than
that of the sun, and so Ehrlich believes that the oscillation periods could be
short enough to be observed. He has yet to calculate the precise period or the
extent of variation in brightness to be expected.
11 Nigel Weiss, a solar physicist at the University of Cambridge, is far from
convinced. He describes Ehrlich's claims as "utterly implausible". Ehrlich
counters that Weiss's opinion is based on the standard solar model, which fails
to take into account the magnetic instabilities that cause the temperature
fluctuations.
Questions 1-4
Complete each of the following statements with One or Two names of the
scientists from the box below.
Write the appropriate letters A-E in boxes 1-4 on your answer sheet.
A. Attila Grandpierre
B. Gábor ágoston
C. Neil Edwards
D. Nigel Weiss
E. Robert Ehrlich
1. ...claims there a dimmer switch inside the sun that causes its brightness
to rise and fall in periods as long as those between ice ages on Earth.
2. ...calculated that the internal solar magnetic fields could produce
instabilities in the solar plasma.
3. ...holds that Milankovitch cycles can induce changes in solar heating on
Earth and the changes are amplified on Earth.
4. ...doesn't believe in Ehrlich's viewpoints at all.
Questions 5-9
Do the following statements agree with the information given in the reading
passage?
In boxes 5-9 on your answer sheet write
TRUE if the statement is true according to the passage
FALSE if the statement is false according to the passage
NOT GIVEN if the information is not given in the passage
5. The ice ages changed frequency from 100,000 to 41,000 years a million
years ago.
6. The sole problem that the Milankovitch theory can not solve is to explain
why the ice age frequency should shift from one to another.
7. Carbon dioxide can be locked artificially into sea ice to eliminate the
greenhouse effect.
8. Some scientists are not ready to give up the Milankovitch theory though
they haven't figured out which mechanisms amplify the changes in solar
heating.
9. Both Edwards and Ehrlich believe that there is no practical way to test
when the solar temperature oscillation begins and when ends.
Questions 10-14
Complete the notes below.
Choose one suitable word from the Reading Passage above for each answer.
Write your answers in boxes 10-14 on your answer sheet.
The standard view assumes that the opposing pressures of gravity and nuclear
fusions hold the temperature ...10...in the sun's interior, but the slight
changes in the earth's ...11... alter the temperature on the earth and cause ice
ages every 100,000 years. A British scientist, however, challenges this view by
claiming that the internal solar magnetic ...12... can induce the temperature
oscillations in the sun's interior. The sun's core temperature oscillates around
its average temperature in ...13... lasting either 100,000 or 41,000 years. And
the ...14... interactions within the sun's magnetic field could flip the
fluctuations from one cycle length to the other, which explains why the ice ages
changed frequency a million years ago.
How a Frenchman is reviving McDonald’s in Europe
A. When Denis Hennequin took over as the European boss of McDonald’s in
January 2004, the world’s biggest restaurant chain was showing signs of recovery
in America and Australia, but sales in Europe were sluggish or declining. One
exception was France, where Mr Hennequin had done a sterling job as head of the
group’s French subsidiary to sell more Big Macs to his compatriots. His task was
to replicate this success in all 41 of the European countries where
anti-globalisers’ favourite enemy operates.
B. So far Mr Hennequin is doing well. Last year European sales increased by
5.8% and the number of customers by 3.4%, the best annual results in nearly 15
years. Europe accounted for 36% of the group’s profits and for 28% of its sales.
December was an especially good month as customers took to seasonal menu
offerings in France and Britain, and to a promotion in Germany based on the game
of Monopoly.
C. Mr Hennequin’s recipe for revival is to be more open about his company’s
operations, to be “locally relevant”, and to improve the experience of visiting
his 6,400 restaurants. McDonald’s is blamed for making people fat, exploiting
workers, treating animals cruelly, polluting the environment and simply for
being American. Mr Hennequin says he wants to engage in a dialogue with the
public to address these concerns.
D. He introduced “open door” visitor days in each country which became hugely
popular. In Poland alone some 50,000 visitors came to McDonald’s through the
visitors’ programme last year. The Nutrition Information Initiative, launched
last year, put detailed labels on McDonald’s packaging with data on calories,
protein, fat, carbohydrates and salt content. The details are also printed on
tray-liners.
E. Mr Hennequin also wants people to know that “McJobs”, the low-paid menial
jobs at McDonald’s restaurants, are much better than people think. But some of
his efforts have backfired: last year he sparked a controversy with the
introduction of a “McPassport” that allows McDonald’s employees to work anywhere
in the European Union. Politicians accused the firm of a ploy to make cheap
labour from eastern Europe more easily available to McDonald’s managers across
the continent.
F. To stay in touch with local needs and preferences, McDonald’s employs
local bosses as much as possible. A Russian is running McDonald’s in Russia,
though a Serb is in charge of Germany. The group buys mainly from local
suppliers. Four-fifths of its supplies in France come from local farmers, for
example. (Some of the French farmers who campaigned against the company in the
late 1990s subsequently discovered that it was, in fact, buying their produce.)
And it hires celebrities such as Heidi Klum, a German model, as local brand
ambassadors.
G. In his previous job Mr Hennequin established a “design studio” in France
to spruce up his company’s drab restaurants and adapt the interior to local
tastes. The studio is now masterminding improvements everywhere in Europe. He
also set up a “food studio”, where cooks devise new recipes in response to local
trends.
H. Given France’s reputation as the most anti-American country in Europe, it
seems odd that McDonald’s revival in Europe is being led by a Frenchman, using
ideas cooked up in the French market. But France is in fact the company’s most
profitable market after America. The market where McDonald’s is weakest in
Europe is not France, but Britain.
I. “Fixing Britain should be his priority,” says David Palmer, a restaurant
analyst at UBS. Almost two-thirds of the 1,214 McDonald’s restaurants in Britain
are company-owned, compared with 40% in Europe and 15% in America. The company
suffers from the volatility of sales at its own restaurants, but can rely on
steady income from franchisees. So it should sell as many underperforming
outlets as possible, says Mr Palmer.
J. M.Mark Wiltamuth, an analyst at Morgan Stanley, estimates that European
company-owned restaurants’ margins will increase slightly to 16.4% in 2007. This
is still less than in the late 1990s and below America’s 18-19% today. But it is
much better than before Mr Hennequin’s reign. He is already being tipped as the
first European candidate for the group’s top job in Illinois. Nobody would call
that a McJob.
Notes to Reading Passage 1
1.sterling高质量的
e.g. He has many sterling qualities. 他身上有许多优秀的品质。
2. menial 不体面的, 乏味的(工作、职业)
3. spruce up打扮整齐、漂亮、装饰
4. mastermind指挥、谋划(一个计划或活动)
e.g. The police know who masterminded the robbery.警察知道是谁策划了那次抢劫。
5. underperform表现不佳表现出低于标准的工作水平、企业出现亏本
Questions 1-6
Do the following statements reflect the claims of the writer in Reading
Passage 1?
Write your answer in Boxes 1-6 on your answer sheet.
TRUE if the statement reflects the claims of the writer
FALSE if the statement contradicts the claims of the writer
NOT GIVEN if it is impossible to say what the writer thinks about this
1. McDonald was showing the sign of recovery in all European countries except
France after Denis Hennequin took office as the boss of Euro-markets.
2. Starting from last year, detailed labels are put on McDonald’s packaging
and detailed information is also printed on tray-liners.
3. France is said to be the most anti-American country in Europe, but the
ideas of the “open door” visiting days and “McPassport” are invented in the
French market.
4. Britain possesses the weakest McDonald market among European countries and
approximately 1214 McDonald’s restaurants are company-owned.
5. According to David Palmer, a restaurant analyst at UBS, David Hennequin
should treat the problem about McDonald in Britain as the most important
thing.
6. David Palmer suggested that the management of McDonalod in Italy should
sell as many its outlets which lose money in business as possible for
revival.
Questions 7-10
Choose the appropriate letters A-D and write them in boxes 7-10 on your answe
sheet.
7. The word “sterling” in line 3 of Paragraph A means__________.
A. difficult
B. menial
C. terrible
D. excellent
8. Which of the following statements on the accusation of MacDonald is NOT
TRUE?
A. It tends to make people fat.
B. Its operations are very vague.
C. It tends to exploit workers.
D. It tends to treat animals cruelly.
9. Which of the following measures taken by Denis Hennequin produced
undesired result?
A. “Food Studio” scheme.
B. “Open Door” visitor days.
C. The “McPassport” scheme.
D. The Nutrition Information Initiative.
10. What did Denis Hennequin do so as to respond to local trends?
A. set up a “Food Studio” .
B. established a “Design Studio”.
C. hired celebrities as local brand ambassadors.
D. employed local bosses as much as possible.
Questions 11-14
Complete each of the following statements (Questions 11-14) with words or
number taken from Reading Passage 1.
Write NO MORE THAN THREE WORDS for each answer.
Write your answers in boxes 11-14 on your answer sheet.
11. After January 2004, McDonald was making improvement following a period of
slump in America and Australia, but sales in Europe were ………………………….
12. Business of McDonald in France and Britain was particularly good in
December since customers took to ……………………………..
13. Compared with other countries, France is McDonald’s ………………………. next to
America.
14. ……………………. of McDonald’s restaurants in America are companied–owned and
the figure is much lower than that in Britain.
Felicity Lawrence
Thursday December 28, 2006
The Guardian
1. Consumers are to be presented with two rival new year advertising
campaigns as the Food Standards Agency goes public in its battle with the
industry over the labelling of unhealthy foods.
2. The Guardian has learned that the FSA will launch a series of 10-second
television adverts in January telling shoppers how to follow a red, amber and
green traffic light labelling system on the front of food packs, which is
designed to tackle Britain’s obesity epidemic.
3. The campaign is a direct response to a concerted attempt by leading food
manufacturers and retailers, including Kellogg’s and Tesco, to derail the
system. The industry fears that traffic lights would demonise entire categories
of foods and could seriously damage the market for those that are fatty, salty
or high in sugar.
4. The UK market for breakfast cereals is worth ￡1.27bn a year and the
manufacturers fear it will be severely dented if red light labels are put on
packaging drawing attention to the fact that the majority are high in salt
and/or sugar.
5. The industry is planning a major marketing campaign for a competing
labelling system which avoids colour-coding in favour of information about the
percentage of "guideline daily amounts" (GDAs) of fat, salt and sugar contained
in their products.
6. The battle for the nation’s diet comes as new rules on television
advertising come into force in January which will bar adverts for unhealthy
foods from commercial breaks during programmes aimed at children. Sources at the
TV regulators are braced for a legal challenge from the industry and have
described the lobbying efforts to block any new ad ban or colour-coded labelling
as "the most ferocious we’ve ever experienced".
7. Ofcom’s chief executive, Ed Richards, said: "We are prepared to face up to
any legal action from the industry, but we very much hope it will not be
necessary." The FSA said it was expecting an onslaught from the industry in
January. Senior FSA officials said the manufacturers’ efforts to undermine its
proposals on labelling could threaten the agency’s credibility.
8. Terrence Collis, FSA director of communications, dismissed claims that the
proposals were not based on science. "We have some of the most respected
scientists in Europe, both within the FSA and in our independent advisory
committees. It is unjustified and nonsensical to attack the FSA’s scientific
reputation and to try to undermine its credibility."
9. The FSA is understood to have briefed its ad agency, United, before
Christmas, and will aim to air ads that are "non-confrontational, humorous and
factual" as a counterweight to industry’s efforts about the same time. The
agency, however, will have a tiny fraction of the budget available to the
industry.
10. Gavin Neath, chairman of Unilever UK and president of the Food and Drink
Federation, has said that the industry has made enormous progress but could not
accept red "stop" signs on its food.
11. Alastair Sykes, chief executive of Nestlé UK, said that under the FSA
proposals all his company’s confectionery and most of its cereals would score a
red. "Are we saying people shouldn’t eat confectionery? We’re driven by
consumers and what they want, and much of what we do has been to make our
products healthier," he said.
12. Chris Wermann, director of communications at Kellogg’s, said: "In
principle we could never accept traffic light labelling."
13. The rival labelling scheme introduced by Kellogg’s, Danone, Unilever,
Nestlé, Kraft and Tesco and now favoured by 21 manufacturers, uses an
industry-devised system based on identifying GDAs of key nutrients. Tesco says
it has tested both traffic lights and GDA labels in its stores and that the
latter increased sales of healthier foods.
14. But the FSA said it could not live with this GDA system alone because it
was "not scientific" or easy for shoppers to understand at a glance.
Questions 1-6
Answer the questions below using NO MORE THAN THREE WORDS from the passage
for each answer.
1. When will instructions be given on reading the color-coded labels?
2. Where can customers find the red light labels?
3. What problem is the FSA trying to handle with the labeling system?
4. Which product sells well but may not be healthy?
5. What information, according to the manufacturers, can be labeled on
products?
6. What can not be advertised during children’s programmes?
Questions 7-13
Use the information in the text to match the people (listed A-E) with the
opinions (listed 7-13) below. Write the appropriate letter (A-E) for questions
1-7.
NB You may use any letter more than once.
A Ed Richard
B Terrence Collis
C Gavin Neath
D Alastair Sykes
E Chris Wermann
7. Generally we will not agree to use the red light labels.
8. It is unreasonable to doubt if FSA is trustworthy.
9. We are trying to meet our consumers’ needs.
10. The food industry has been improving greatly.
11. The color-coded labeling system is scientific.
12. Our products will be labeled unhealthy by the FSA.
13. We are ready to confront the manufacturers.
