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Высшего профессионального образования «Чувашский государственный университет имени И. Н. Ульянова» английский язык тексты для чтения и перевода чебоксары 2010

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DNA Computers
Internet: How It Affects US
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DNA Computers


All the indications are that the era of traditional silicon computers is coming to the close. A discovery made by scientists at the Weizmann Institute can turn around the high - tech market.

The history of DNA and DNA computers began in Match 1953 (nineteen fifty three) when two young scientists James Watson and Francis Crick discovered "the secret of life". The breakthrough the two had made was, indeed, extraordinary, for they had worked out the molecular structure of DNA the chemical substance found in the nucleus of every living cell. The double helix structure they had deduced revealed that DNA could do two crucial things it could carry information and it could replicate itself. It was a discovery that would revolutionize biology. By the early 1950s, scientists had already identified DNA as the molecule that carried the biochemical information that enables all living things to exist, and so a race was on to discover exactly how it did this.

By today scientists discovered that DNA was composed of four chemical bases known as adenine, thymine, guanine and cytosine. These four bases are arranged like steps on the ladder. Adenine always links with (thymine, guanine always links with cytosine, and the precise sequence in which the pairs are arranged is the code that genes use to give instructions for the manufacture of the many proteins needed for the formation and functioning of the living organism throughout its life. The idea of building calculating devices on the basis of DNA molecules is really molecules."

Contrary to claims by Microsoft specialists, an ordinary computer is unable to perform several tasks simultaneously. It performs them consecutively - true, very fast, so fast in fact that users arc unaware of the defect. If a defect it is. The Nanocomputer is free from any such shortfall. DNA molecules work "as a team," and this is why the new machine is "polyphonic," so to speak, being able to perform several tasks at once. According to professor Shapiro, "the Turing machine should process information and store it in the form of the chain of symbols. Just as a life DNA does." So far the Israelis have created just one of possible Turing machine versions. Designed at the Weizmann Institute, the Nanocomputer operates with only two symbols, the way ordinary computers operate with the notions of "logical 0" and "logical 1." Thus far the system is too elementary to perform any specific tasks. But it can serve as a platform for DNA computers of the future. They will be able to work directly in a human cell, identifying potential diseases and curing them. It may still be a long way from Ehud Shapiro's discovery to the shining pinnacles of the future. But the first step has already been made.

Internet: How It Affects US


We live in a multi-media society. How does the internet affect our lives? It can be very helpful to people who carefully choose websites that they visit. The internet can increase our knowledge of the outside world; there is much high-quality information that can help us understand many fields of study: science, medicine, the arts and so on. In this global network you can find any information in a few minutes. Otherwise you would have to search for the necessary information in directories, libraries or on the phone for a long time.

The internet has already revolutionized the way we live and work. But these are still earl days for the internet. We don't know how much it is still changing the world. The internet era is yet to come. The internet is an up-to-date wonder. As the proverb says: "nothing is wonderful, when you get used to it", that is why the internet fails to astonish us any more.

One of the most valuable functions of the internet is its information function. The internet keeps people informed about current events, as the latest achievements in science and culture. You can even find out how to pass from the underground station to the house of your girlfriend, who recently moved to London.

Recently a system of distance learning became popular. You can study foreign languages and even study in universities. Individual educational programs can be developed especially for you.

The internet is also widely used in business. Thanks to the internet, we have rapid connections with partners from all corners of the world. You can even conduct negotiations, hear and see your contacts, and exchange graphic and textual information.

On the other hand, there are several serious disadvantages to the internet. Of course, it provides us with a pleasant way to relax and spend our free time, but some people spend an average of six hours or more a day on the network. Many children look at a screen for more hours each day than they do anything else, including studying and sleeping. It's clear that the network has a powerful influence on their lives, and that its influence is often negative.

Another disadvantages is that for many people the internet becomes more "real" than reality, and their own lives seem boring. Also, many people get upset or depressed when they can't solve problems in real life as quickly as they can do in internet games. In real life they can not simply press "escape".

The most negative effect of the internet might be people's addiction to it. People often feel a strange and powerful need to spend time on the network. Addiction to a computer screen is similar to drug or alcohol addiction: people almost never believe they are addicted.

One more disadvantage of the internet is the absence of information control. Children receive wide access to porno sites and sites with violence and promoting hate.

From that, how much we know about the internet depends on the choices we make world how effectively we use the opportunities of the internet in our time.