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.

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.

Do you ever feel overworked?(Why?/Why not?)

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We'd like to express our desire to establish business relationship with you on the basis of quality, mutual benefit and exchange of needed goods .

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Section C

What a lovely place Xerox is to work Kim Moloney, a client services executive, can’t say enough nice things about her employer. ‘It’s a very special environment,’ she says. ‘People describe Xerox as a family and I was amazed at the number of people who have worked here for so long.’ It’s tempting to take Moloney’s comments with a pinch of salt, especially considering that when you’ve been working somewhere for only two years, as she has at Xerox, everyone seems old and established. But there’s truth behind her enthusiasm.

Take Carole Palmer, the group resources director. She joined Xerox in 1978 as a temp and has been in her present role for seven years. ‘Xerox has been good to me over the years,’ she says. ‘It has supported me through qualifications … and last year I took part in the vice-president incumbent program.’ Human resources is taken seriously at Xerox, Palmer says, and the company has a policy of promoting from within (which would explain Moloney’s amazement at her colleagues’ longevity). The company takes on only fifteen to twenty graduates each year and Moloney was part of an intake who joined having already acquired a couple of years’ work experience. She started as a project manager for Xerox Global Services before moving into sales. Now her responsibility is to ‘grow and maintain customer relationships’.

Moloney is based at the head office in Uxbridge. ‘It’s great in terms of working environment,’ she says. ‘We’ve just got a new provider in the canteen and … we have brainstorming rooms and breakout areas.’ Much of Moloney’s role is visiting clients, so she doesn’t have a permanent desk at head office. ‘I’m a hot-desker, which is good because you get to sit with different people in the hot-desk areas. And you’re given a place to store your things.’ Head office staff numbers between 1,200 and 1,500 people, Palmer says. The company has four other main offices in the UK. The nature of the organization, which encompasses sales and marketing, global services (the biggest division), developing markets, research and development and manufacturing, means that the opportunities at the company vary from service engineers to sales roles and consultants.

Perks include a final-salary pension scheme and various discount schemes. The reward and recognition scheme is a little different, and rather nice: ‘Each manager has a budget every year to recognize and reward staff,’ Palmer says. ‘It can be in the form of a meal for two, or a bottle of wine. It can be up to £1,000. There’s the recognition, and then there’s putting money behind it.’ Moloney, however, likes the non-cash rewards. ‘Xerox takes care of all its staff but it also recognizes the people who put in the added effort,’ she says. ‘It offers once-in-a-lifetime incentive trips, and recently I organized a sailing trip for my team.’

The idea of working abroad with the company appeals to her, and she says that her career goal is to be part of the senior management team. Here’s another employee, it would seem, who is in it for the long haul.

( )1.The journalist of this article thinks that .

A. staff at Xerox are not telling the truth abut the company.

B. Xerox offers great benefits to staff.

C. Xerox is the best company in the world.

D. Xerox has the best working environment.

( )2.The company tends to find its new manager .

A. only form graduates B. on training courses

C. from existing staff D. from job markets

( )3.What does the phrase “to take on” in the sentence “The company takes on only fifteen to twenty graduates each year and …” of the second paragraph mean? .

A. To train B. To employ

C. To interview D. To maintain(A)

( )4.As well as recognizing its staff through promotion, Xerox .

A. gives cash bonuses

B. gives unpaid leave to take trips of a lifetime.

C. provides a number of perks.

D. provides huge end-of-year bonuses.

( )5.One common feature of Xerox staff is that they tend .

A. to work hard B. to get promoted

C. work longer hours each day D. not to change employer

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