当前位置：首页 → 职业资格 → 教师资格 → 中学英语学科知识与教学能力->WIstalkingonamobilephonehazard
WIs talking on a mobile phone hazardous to your health?It is difficult to know for sure.Some research suggests that heavy users of mobile phones are at a greater risk of developing brain tumors.However,many other studies suggest there are no links between cancer and mobile phone use.
The main problem with the current research is that mobile phones have only been popular since the 1990s.As a result,it is impossible to study the long-term exposure of mobile phone use.This concerns many health professionals who point out that many cancers take at least ten years to develop.Another concern about these studies is that many have been funded by those who benefit financially from the mobile phone industry.
Over three billion people use mobile phone on a daily basis,and many talk for more than an hour a day.Mobile phone antennas are similar to microwave ovens.While both rely on electromagnetic radiation,the radio waves in mobile phones are lower in radio frequency(RF).
Microwave ovens have enough RF to cook food and are therefore known to be dangerous to human tissues.However,the concern is that the lower frequency radio waves that mobile phones rely on may also be dangerous.It seems logical that holding a heat source near your brain for a long period of time is a potential health hazard.Mobile phones get hot when they are phoned for a long period of time.
Some researchers believe that over types of wireless technology may also be dangerous to human health,including laptops,cordless phones,and gaming consoles.Organizations that are concerned about the effects of Electromagnetic Radiation(EMR)suggest replacing all cordless devices with wired ones.They say that many cordless phones emit dangerous levels of EMR even when they are not in use.They even suggest keeping electronic devices,such as computers and alarm clocks out of bedrooms,or at least six feet from your pillow.
Other wireless technology may also be hazardous to our health.A growing number of professionals worldwide are recommending that mobile phone users should use their phones carefully until more definitive studies can be conducted.They recommend that adults use headsets or speaker phones and that children and teens,whose brain tissues are still developing use mobile phones only for emergencies.Concerned medical experts use the example of tobacco to illustrate the potential risks.Many years ago,people smoked freely and were not concerned about the effects of cigarettes on their health.Today people know that cigarettes cause lung cancer,though it is still unknown exactly how or why.Some doctors fear that the same thing will happen with devices such as mobile phones.
hat recommendation did the health professionals give to the teen mobile phone users?查看材料
细节题。根据最后一段中的“They recommend…that children and teens，whose brain tissues are still developing use mobile phones only for emergencies”可知，大脑还在发育的儿童和青少年最好只在紧急情况下才使用手机。故本题选B?
有“泥土诗人”之称的诗人是（）。
将下列各项按所表示年龄大小顺序排列，正确的顺序应是（ ）。
①不惑②垂髫③花甲④加冠⑤而立⑥古稀⑦半百
1931年，一位给人们带来光明的科学家重病的消息牵动着世界人民的心，几十名记者为他守夜。每隔一个小时就对外发布一次消息：“灯”还亮着。这位科学家是（ ）。
钱穆在评论中国古代某制度时说，它“可以培植全国人民对政治之兴味……可以团结全国各地域于一个中央之统治”，这一制度是()。
明朝初年强化君主专制的措施是（）。
知识是个体通过与环境相互作用后获得的（ ）。
《诗经》中描绘了一个美丽清泠、朦胧迷茫的抒情境界，刻画诗人徘徊追思的形象，借助景物和意象含蓄委婉地表达相思和追怀之情的诗篇是（ ）。
在我国历史上，传统音乐与外族音乐、北方与南方音乐进行广泛交流的时期是()。
教育的本体功能之一是( )。
一个国家教育经费投入的多少最终取决于（ ）。
