大学英语综合教程3听力全文

英语listening in 部分组最后一篇短文
Unit 4
Listen passage 1
Traditional jobs like the chimney sweeps and coal miners from our history lessons don't really exist anymore. During the 20th century the number of people working in agriculture and manufacturing decreased significantly. In contrast, the number of people doing
office-based jobs has more than doubled, from 18 per cent of the working population in 1901, to over 40 per cent by the end of the 20th century. Modern society has changed the way we work but these changes are not always positive. They can also create problems we may not be aware of.
What does the modern office mean for the nation's health, for example? Well, firstly, office jobs are sedentary. We're sitting at our desks all day working on computers. And this means we're not exercising our bodies in the way people used to when they did more traditional jobs. It's not surprising then that we're all putting on weight. In fact, a fifth of adults over 16 were classified as overweight in 2001.
But there are other less obvious dangers connected with office work. Repetitive strain injury, or RSI, and other disorders like muscle strain, neck and backache are a growing problem. It's estimated that in 2002, over a million people suffered from these kinds of health problems. As a result, 12.3 million working days were lost. The cause is simple: long periods spent sitting at the computer typing and using a mouse.
Many companies now employ ergonomic experts to ensure staff are sitting correctly at their computers and take frequent breaks from typing to try and prevent injury.
Another problem of the modern office is the building itself. People tend to feel tired and irritable after a day stuck inside a modern office and often get colds and flu. This phenomenon is known as "sick building syndrome" and it's caused by several factors. First of all, in many offices there is a lack of natural air and light. Secondly, within the enclosed space of an office environment, there is a high concentration of electronic devices. And as well as this, air-conditioning systems in large buildings re-circulate the air around the office, carrying germs from workstation to workstation. Research suggests sick building syndrome can be found in roughly 30 per cent of new or refurbished buildings. But there is some good news for office workers. A lot of companies are making efforts to improve office workplaces. They're installing better lighting and ventilation. They're increasing the number of plants. And they're encouraging employees to take regular breaks from their computers. So if anyone listening is in an office, take this simple advice: get up, have a stretch, open a window—if you can—and think of ways you can stay healthy in this most unnatural environment.
Unit 5
Listen passage1
Next I will look at the roles of individuals within groups. A group that is made up of individuals who have similar personalities may not work effectively. In the 1980s Belbin identified eight different roles that can help build effective teams. The "Chairperson" is someone who is self-confident and encourages others to contribute.
Then there is the "Company worker"—he or she is conservative and helps organize others.
The "Shaper" is outgoing and dynamic and motivates others—whereas the "Plant" is a genius who is often a loner.
The "Resource investigator" is the group member who is always curious and explores new ideas and the "Monitor-evaluator" is calm and serious and makes good, balanced decisions.
The "Teamworker" in contrast is a socially orientated and sensitive member of the team who is able to encourage a team spirit. And the "Completer-finisher" is a conscientious perfectionist who follows through on the details and ties up any loose ends. To be effective, a team needs to have a variety of members who can fulfil all these different roles.
Unit 7
passage 1
When you have a biscuit with your cup of tea do you dunk it? And if so, what's the perfect way to do it? That's the subject of today's Science in Action report. It may be hard to believe but scientists at the University of Bristol have been analyzing this question. And after a two-month study they devised a mathematical formula for dunking biscuits. So no more melting chocolate, or biscuit crumbs in the bottom of your cup, which is the fate of one in four biscuits that are dunked in tea, according to research by a biscuit manufacturer.
Doughnut dunkers don't face the same problems because doughnuts are held together with an elastic net of protein gluten. This substance allows the doughnut to absorb liquid without breaking down its structure. The structure of a biscuit, however, is held together by sugar which melts when placed in hot tea or coffee.
So what is the answer? The researchers, led by Dr Len Fisher, discovered that holding the biscuit in a horizontal position—or "flat-on"—has a significant effect on the amount of time that a biscuit can stay in hot liquid before falling apart. In fact this horizontal dunking results in a dunking time up to four times longer than traditional vertical dunking.
What's the reason for this? It seems that the answer is related to diffusion, in other words, the length of time it takes for the liquid to penetrate the structure of the biscuit. Basically, it takes longer for the liquid to travel through the channels of a biscuit when it is laid flat on the surface of the liquid. Also the fact that when a biscuit is dunked horizontally, with the biscuit submerged in the liquid, and the chocolate coating staying out of the liquid, the chocolate helps hold the biscuit together. Another factor influencing the equation is the temperature of the tea – the hotter the tea, the faster the sugar melts.
The researchers also found that by dunking a biscuit into tea or coffee, up to ten times more flavour is released than if the biscuit is eaten dry. So it's worth experimenting
yourself. If you are wondering how you can perfect the horizontal dunk, the researchers have come up with an idea for a biscuit-holding device to make dunking biscuits easier. They are even now working on producing a table giving guidelines on dunking times for different types of biscuits.
On that note, I think it's time to go off to the canteen for a tea break!。