Английский язык. Учебное пособие по развитию навыков устной речи и чтения для магистрантов технических специальностей
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26. Now read the other FAQ and choose the correct answer according to the information you’ve read. Who will own the laptop? a) Government , who will lend them to schoolchildren. b) Schools, that will use them in class. c) Children. How have manufacturing costs been reduced? a) By using older versions of software. b) By using a cheap display panel. c) By reducing the number of functions the machine can perform. What advantage of using open source software is mentioned? a) It is simpler and easier to use. b) It uses less memory. c) It can be modified by the uses. What can the laptop not do? a) Connect wirelessly with other computers. b) Store a lot of information. c) Connect to peripherals using USB. When is the manufacturing of the laptops due to start? a) When the first orders have been received. b) As soon as the design has been finalized. c) When sufficient orders have been paid for in advance. 27. Work in groups of two or three and think of the advantages of the laptop project initiated by Nicolas Negroponte and its essential features. Report the general idea of the group to the class. 28. Work in small groups and discuss the issues. 1) What differs a laptop from a typical modern computer? 2) What technology and software does it use? 3) Compose a list of its technical specification, advantages and the most important characteristics. Make a report or a presentation for your local Education Department where you persuade them to participate in the (same or similar) project. 29. Rearrange Dialogue A to make it sound logically correct. There are two participants in the conversation: a salesperson in a computer shop and a buyer in the shop Steve. Sentence a) is the first one in the conversation. Dialogue A. IN A COMPUTER SHOP Steve is interested in buying a laptop computer and is asking a salesperson about Wi-Fi technology What’s this Wi-Fi thing that’s mentioned in your brochure here? Well, Wi-Fi gives you the freedom to check your e-mails or surf the Web when you’re away from home or out of the office. That’s the main advantage. A what? Well, it’s based on the same technology as cordless phones – not mobile phones, I mean the one’s most people have at home these days, you know. Anyway, your laptop can be fitted with a modem, a special antenna and a software which can send and receive signals the short distance to connect with the hotspot, and then the equipment in the hotel lobby or airport or whatever is wired up to a regular phone line, so you’re connected. I see. And how many of these hotspots are there about? Well, not exactly anywhere. You have to be 100 metres of a Wi-Fi Hotspot. And what would I want that for, exactly? A Wi-Fi Hotspot. That’s just the name for a place where the equipment that can communicate with your computer and connect it to the Internet. You find them in places like airports, hotel lobbies, cafes – even some telephone boxes. But you can’t connect unless you’re fairly close to one. And how much extra would it cost? Oh, Wi-Fi technology? Well, basically it’s a system that allows you to connect to the internet without cables. So, you mean I can log on to my Internet account from anywhere? Sounds good! Oh, about 100 or so. Worth it, though, don’t you think? Hmm. So, how does it work, then, this Wi-Fi business? Well, a bit too expensive, for me, actually. A few thousand in our country. I’d say it’s still early days. I haven’t really caught on yet, you know. But it will! 30. Choose the best answer the question on Dialogue A: Why doesn’t Steve select Wi-Fi? a) It’s too expensive. b) He doesn’t think it’s really useful. c) He doesn’t understand what it’s for. 31. Read Text B. This is a summary of Dialogue A. Complete the summary with the correct word. Text B Wi-Fi technology gives you the freedom of accessing the Internet and your mail account without the need for a (1) … to connect. You can connect using Wi-Fi whenever there is a Wi-Fi access points, also known as (2) …. With (3) … of (4)… throughout the country, there’s sure to one close to you wherever you can be. At the moment you can find them in airports, hotel (5) …, cafes and public telephone boxes. Wi-Fi is based on the same technology as (6) … phones. If you are within (7) … meters of an access point, a special antenna on your computer can connect you to the (8) … equipment and then to the Internet at broadband speeds. Your laptop can be updated for Wi-Fi capability for as little as $ (9) …. 32. Act out Dialogue A or compose a similar one. Invent any details you like while discussing a purchase in a computer shop. 33. Discuss the following questions in groups of three or four and then report back to the class on what you’ve learnt about your partners. Try to compose «a portrait of your group» depicting your computer and Internet habits. 1) Are you computer-literate? 2) What are your computer skills? 3) Are you computer or Internet-addicted? 4) What do you use the Internet for? 5) What social nets are you in? 6) What are your relations with Facebook, Twiter etc.? 7) What effects will the Internet have on our lives? 8) Will computers outsmart us? 9) Are video games a new art form or are they polluting our minds? READING COMPREHENSION Text 1 THE OZONE LAYER 1. Read the text and decide if the following statements are true (T) or false (F). 1) All ozone gas is contained in the stratospheric ozone and is spread thinly and unevenly. 2) Ultraviolet radiation from the sun causes oxygen molecules to combine with other oxygen molecules to form ozone. 3) UV rays are dangerous to human beings, animals and plants because they burn so we should avoid the sun at all. 4) Eye cataracts, the leading cause of blindness in the world, is the most dangerous disease because of the sun. As the sun’s radiation approaches the planet’s surface it can be scattered, reflected, or absorbed, intercepted and re-emitted. This is where the ozone layer comes into its own by scattering and reflecting harmful high energy ultraviolet radiation. Variations in temperature and pressure divide the Earth’s atmosphere into layers and the mixing of gases between the layers happens very slowly. That is why this 90% of the ozone stays in the upper atmosphere. This stratospheric ozone contains 90% of all ozone gas on the Earth but it is spread thinly and unevenly. Life on earth has been safeguarded because of a protective layer in the atmosphere. This layer, composed of ozone, acts as a shield to protect the earth against the harmful ultraviolet radiation from the sun. Ozone is a form of oxygen with three atoms (O3) instead of two (O2). Through natural atmospheric processes, ozone molecules are created and destroyed continuously. Ultraviolet radiation from the sun breaks up oxygen molecules into atoms which then combine with other oxygen molecules to form ozone. Ozone is not a stable gas and is particularly vulnerable to destruction by natural compounds containing hydrogen, nitrogen and chlorine. Near the earth’s surface (the troposphere) ozone is an increasingly troublesome pollutant, a constituent of photochemical smog and acid rain. But safely up in the stratosphere, 11 to 48 km above the earth’s surface, the blue, pungent-smelling gas is as important to life as oxygen itself. Ozone forms a fragile shield, curiously insubstantial but remarkably effective. This ozone filter efficiently screens out almost all the harmful ultraviolet rays of the sun; the ozone layer absorbs most of the dangerous UV-B radiation (radiation between UV-A which is allowed through and UV-C which is mainly captured by oxygen, as indicated in Figure 1.2). Any damage that is done to the ozone layer will lead to increased UV-B radiation. Increases of UV-B radiation have been clearly observed in areas experiencing periods of intense ozone depletion. Any increased UV-B that reaches the earth’s surface has a potential to cause considerable harm to the environment and to life on earth. A small decrease in the ozone layer could significantly increase the incidence of skin cancer, and could lead to an acceleration of the rarer but more virulent form of cancer known as coetaneous malignant melanoma. Increased UV-B could lead to increased incidents of eye damage, including cataracts, deformation of the eye lenses, and presbyopia. Eye cataracts, the leading cause of blindness in the world, are expected to increase considerably. UV rays are dangerous to human beings, animals and plants because they burn. They can penetrate our skin and eyes and weaken our bodies’ immune system. That is why we should avoid long periods in the sun. To get the minimum daily dose of vitamin D only 15 minutes in the sun per day is enough. If we stay more than that, we might get sunburnt if no protection is used. Repeated sunburns and frequent tanning can cause premature ageing of the skin and, at worst, skin cancer such as melanoma (because of UV-A and UV-B). For the eyes the UV-B rays can cause a cataract (clouding of the eye lens). Most of the serious health problems appear only many years later. Text 2 ANTI-SOCIAL AMINO ACIDS GANG UP 1. Read the text and write an abstract of the text in 3-5 sentences. Previously thought to be purely the preserve of proteins and peptides, scientists have discovered that the amino acid phenylalanine can form the toxic amyloid fibrils that are a hallmark of diseases such as Alzheimer’s and Parkinson’s. ‘This is the first time ever that it has been demonstrated that an amino acid, rather than a peptide or a protein, can form such a structure,’ lead researcher Ehud Gazit at Tel Aviv University in Israel tells Chemistry World. As well as throwing new light on the behaviour of amino acids, this work could lead to new treatments for the genetic disorder phenylketonuria (PKU), which is caused by high levels of phenylalanine. PKU sufferers lack the enzyme phenylalanine hydroxylase, which breaks down phenylalanine. As a result, high levels of phenylalanine quickly build up in the blood, cerebrospinal fluid and brain, leading to seizures, organ damage and unusual posture. The disorder is particularly dangerous for children, because it retards brain development and can cause serious learning difficulties. Fortunately, as we derive most of our phenylalanine from food and drink, PKU sufferers can control phenylalanine levels through their diet. This is why certain food products have the phrase ‘Contains a source of phenylalanine’ on their packaging; this is the case with many diet soft drinks, because phenylalanine is a component of the artificial sweetener aspartame. Still, this is a fairly crude, and easily misjudged, way to control PKU, such that many teenage and adult sufferers have phenylalanine levels that are higher than would be ideal. A more effective method to control or even cure PKU is desperately needed. Unfortunately, the development of new treatments is hampered by the fact that scientists have struggled to elucidate the precise mechanism by which high phenylalanine levels result in organ and tissue damage. Gazit suspected that the damage may be caused by phenylalanine forming amyloid fibrils. Most famously associated with Alzheimer’s disease, these ordered agglomerations of inappropriately folded proteins and peptides have been found to play a part in a wide variety of different diseases, including Parkinson’s disease, diabetes, atherosclerosis and rheumatoid arthritis. Gazit’s suspicions were first raised by the fact that phenylalanine is an aromatic amino acid. He had previously shown that short aromatic peptide fragments can clump together to form amyloid-like fibrils and that a peptide consisting of two phenylalanine molecules can form nano-assemblies with amyloid-like structural properties. So, together with colleagues, Gazit decided to investigate whether individual phenylalanine molecules could form amyloid-like fibrils, even though no amino acid was known to do this. His group used transmission electron microscopy and scanning electron microscopy to study high concentrations of phenylalanine in solution and found that phenylalanine did indeed spontaneously form amyloid-like fibrils. Exactly the same thing happened when he studied high concentrations in human serum. Next, the team showed that these phenylalanine fibrils were toxic to cell lines, causing them to change shape and die off. When they then injected the fibrils into rabbits, he found that they naturally generated antibodies against the fibrils. By attaching fluorescent compounds to these antibodies, the group were able to image the phenylalanine fibrils. Finally, using these fluorescent antibody probes, together with a dye known as Congo red that is regularly used to stain amyloid fibrils, the team searched for phenylalanine fibrils in biological samples. These samples came from brain tissue from a mouse genetically engineered to have a PKU-like condition and from human PKU sufferers. In both cases, Gazit's team unambiguously detected phenylalanine fibrils. This provides convincing evidence that phenylalanine can form amyloid-like fibrils and that these fibrils are responsible for the tissue damage seen in PKU patients. Text 3 METHODS OF PROCESSING AND PRESERVATION OF MEAT 1. Read the text and answer the questions on it. 1) What methods of processing and preservation of meat are presented the text? 2) Which of them is most effective? 3) Which of them is the oldest one? 4) Which of them do you prefer as a consumer? 5) What other methods do you know as a specialist? Meat was originally processed to preserve it, but since the various procedures cause so many changes in texture and flavour it is also a means of adding variety to the diet. Processing also provides scope to mix the less desirable parts of the carcass with lean meat and in addition is a means of extending meat supplies by including other foodstuffs such as cereal in the product. Meat is a highly perishable products and soon becomes unfit to eat and possibly dangerous to health through microbial growth, chemical change and breakdown by endogenous enzymes. These processes can be curtailed by reducing the temperature sufficiently to slow down or inhibit the growth of micro-organisms, by heating to destroy organisms and enzymes (cooking, canning), or by removal of water by drying or osmotic control (binding the water with salt or other substances so that it becomes unavailable to the organisms). It is also possible to use chemicals to inhibit growth and, very recently, ionising radiation (however, the last is not allowed in some countries). Traditional methods that have been used for thousands of years involve drying in wind and sun, salting and smoking. Canning dates from early in the 19th century and allows food to be stored for many years since it is sterilised and protected from recontamination. Processed meats are products in which the properties of fresh meat have been modified by the use of procedures such as mincing, grinding or chopping, salting and curing, addition of seasonings and other food materials, and, in many instances heat treatment. Most of these processes extend the shelf life of meat. Their manufacture, in most instances, depends on the ability of the mixture to retain water since they are emulsions of protein, fat and water. Tumbling and massaging. A new technique was developed in the 1960's to accelerate the penetration of salt. Pieces of meat are injected with the curing salt solution or chopped meat immersed in it and then mechanically shaken – «tumbled». Solutions of 2-8% salt are used, sometimes with the addition of polyphosphate, when there is some extraction of water-soluble protein, mainly myosin. The effect is to improve the water-holding capacity of the meat by reaction between the salt and the structural proteins, aided by the polyphosphate. The extracted proteins set to a strong gel on heating and so bind together the pieces of meat, which can then be shaped or sliced. The term «massaging» is applied to a relatively gentle mechanical treatment while «tumbling» is a more vigorous action. Smoking. Meat has been treated with smoke from the earliest days - traditionally over a wood fire and more recently by producing smoke from wood sawdust in a generator and conducting the smoke over the meat. The substances deposited on the meat contribute to the flavour and appearance but with ordinary, light smoking the preservative effect is limited and the product has to be stored refrigerated. Intensive smoking does prolong shelf life both by heavier deposition of preservatives and by the drying effect of the hot air but it has a detrimental effect on flavour. Consequently preservation by smoking is regarded as an emergency measure when other methods cannot be used. A modern development making use of the flavouring effect is to use an aqueous solution of the constituents of smoke which reduces the amount of strongly flavoured and other unwanted substances. |