【题目】A study published Monday found that people who sleep less tend to be fat,and experts said it’s time to find out if more sleep will fight fatness.
“We’ve put so much emphasis on diet and exercise that we’ve failed to recognize the value of good sleep,”said Fred Turek,a physician at Northwestern University.
Monday’s study from Eastern Virgnia Medical School in Norfolk covered 1,000 people and found that total sleep time decreased as body mass index-a measure of weight based on height increased.
“Men slept an average of 27 minutes less than women and overweight and fat patients slept less than patients with normal weights,”it said.In general the fatter subjects slept about 1.8 hours a week less than those with normal weights.
“Americans experience insufficient sleep and fat bodies.Clinicians are aware of the burden of fatness on patients,”the study said.
“Our findings suggest that major extensions of sleep time may not be necessary,as an extra 20 minutes of sleep per night seems to be associated with a lower body mass index,”it added.
“We caution that this study does not set up a causeandeffect relationship between restricted sleep and fatness,but investigations indicating success in weight loss via extensions of sleep would help greatly to set up such a relationship.”
The study was published in the Archives of Internal Medicine along with an editorial by Turek and Northwestern colleague Joseph Bass commenting on it and related research.
Inan interview,Turek said some studies have shown the lack of sleep causes declines in an appetiteholding back protein hormone,and increases in another hormone that cause a longing for food.“In addition neuropathies(神经疗法)in the brain governing sleep and fatness appear to overlap(部分重叠),”he said.
“Fatness has been rising dramatically in developed countries and reached epidemic(流行病)levels in the United States,”it added,“leading to a variety of health problems.”
A new study having been 【1】 | |||
【2】 | in the past | diet and 【3】 | |
this time | sleep | ||
A study from Eastern Virginia Medical School | People | 1,000 were 【4】 | |
difference | Men slept 27ms less than women on 【5】 | ||
Americans' problem | 【6】 sleep and fat bodies | ||
conclusion | Weight loss set up 【7】 between sleep & fatness. | ||
Reason | Less sleep causes protein hormone to 【8】 | ||
concern | developing countries | rising with 【9】speed | |
in the USA | quite 【10】 |
【题目】If you can find a tree which has been cut down,you will see many rings,or circles,on the base of the trunk.By learning to read these rings,you can find out about the tree's life.
The number of rings tells you how old the tree is.Each year,new wood is formed on the outside of the tree.This new wood is light in color when the tree is growing in spring and summer,and dark in winter when the tree is not growing much.So,if you count the rings of darkorlight colored wood,you can often find out how old the tree is.
You can also tell which years have been good years and which years have been bad years.When the lightcolored rings are very wide,it means that the tree has been growing quickly that year.If the rings are narrow,it has been growing slowly.If the rings on a tree trunk were greatly magnified,you would be able to see why the rings are lightcolored when the tree is growing quickly and darkcolored when the tree is growing slowly.The tree trunk is made up of microscopic tubes,like some pipes,carrying water from the soil,through the trunk,and up to the leaves.They are wide and thinwalled when the tree is growing quickly and they are carrying a lot of water.They are narrow and stuck together when the tree is not growing so quickly.
When a tree is old,the tubes in the centre of the tree don't carry water.The walls of the tubes have become thick with materials which have stuck along them over the years,forming a kind of wood called“heartwood”.This kind of wood is darker in color than the young,growing wood on the outside of the tree.
You don't very often see whole tree trunks which have been cut across.But once you learn to read a cross section of the wood,you can see much more in wood which has been used to make boxes,houses and other things.
In most wood,instead of seeing the trunk cut across,you are seeing it cut along its length.Because you don't see the whole tree,you can't tell how old it is.
Title:【1】of a Tree
General information | Old trees | ||
Items | Facts | Items | Facts |
Where can rings be seen | On the 【2】of a trunk | The tubes in the centre of the tree | Don't carry water |
The【3】of rings | Helps us know about its age | The walls of the tubes | Become 【4】; Form 【5】 |
【6】lightcolored rings | Show the tree grows quickly | ||
Narrow【7】 rings | Mean the tree grows slowly | ||
Microscopic tubes | Function | Carry【8】 | |
Features | Wide and 【9】when growing quickly | ||
Narrow and stuck together when growing 【10】 |