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this reason, the maximum data rate is lower than for ADSL. HDSL can carry as much on a single wire of twisted-pair as can be carried on a T1 line in North America or an E1 line in Europe (2,320 Kbps).

IDSL (ISDN DSL) — is somewhat of a misnomer since it’s really closer to ISDN data rates and service at 144 Kbps than to the much higher rates of ADSL. ISDN, which stands for Integrated Services Digital Network, is a system of digital phone connections which has been available for over a decade. This system allows voice and data to be transmitted simultaneously across the world using E2E (end-to-end) digital connectivity. IDSL is symmetric (“duplex”), with the biggest advantage being the distance it can travel (5-6 miles). Similar to ISDN (128 Kbps) but uses the control channel to increase data rates to 144 Kpbs.

RADSL (Rate-Adaptive DSL) — is an ADSL technology from Westell in which software is able to determine the rate at which signals can be transmitted on a given customer phone line and adjust the delivery rate accordingly. Westell's FlexCap2 system uses RADSL to deliver from 640 Kbps to 2.2 Mbps downstream and from 272 Kbps to 1.088 Mbps upstream over an existing line.

SDSL (Single-line DSL) — is apparently the thing with a single line, carrying 1.544 Mbps (U.S.A. and Canada) or 2.048 Mbps (Europe) each direction on a duplex line. It is considered to be the “business grade” DSL because of its symmetric speeds. SDSL is usually marketed with Service Level Agreement (SLA) such as the network will be guaranteed up for 99.5%, and there will be a 24-hour response time for every problem.

UDSL (Unidirectional DSL)—is a proposal from a European company. It's a unidirectional version of HDSL.

VDSL (Very high data rate DSL) — is a developing technology that promises much higher data rates over relatively short distances (between 51 and 55 Mbps over lines up to 1,000 feet or 300 meters in length). The transmission technology (CAP, DMT, or other) and its effectiveness in some environments are not yet determined. A number of standards organizations are working on it.

Communications Breakthrough

Discovered a new system of high-speed information access, with sound and image, some 50 times faster than using a modem and the Internet. It involves looking up from the computer screen and actually speaking to the person sitting at the next desk.

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x2/DSL—is a planned modem from 3Com and US Robotics that supports 56 Kbps modem communication but is upgradeable through new software installation to ADSL when it becomes available in the user’s area. 3Com calls it “the last modem you will ever need.”

With DSL Internet Service, pages that used to take excruciating minutes to load via dial-up now jump to life in merciful seconds. Typical residential offerings usually have a maximum of 1.5 Mbps (1.5 megabits per second), but special connections for home and office can be obtained to go well above that. There are two limiting factors that are in place for most connections: the modem and the wiring used to transfer the signal from the modem to the computer. Most home use DSL modems that are limited to 10 Mbps on the user (LAN) side. The wiring from the modem to the computers is normally Cat5 wiring, or thin Ethernet, and that is limited to 100 Mbps speed.

VIII. Mastering English Grammar

Translate the sentences paying special attention to the equivalent-lack- ing grammatical structures:

1. Voted four times Most Outstanding Search Engine by cybernauts, Google has a well-deserved reputation as the top choice for those searching the web. Google has a serious goshwow factor providing the option to find more than web pages, however.

2.The Google Toolbar has also won a popular following for the easy access it provides to Google and its features directly from the Internet Explorer browser.

3.Ask Jeeves initially gained fame in 1998 and 1999 as being the “natural language” search engine that let you search by asking questions and responded with what seemed to be the right answer to everything.

4.In reality, the company had about 100 editors who monitored search logs behind the scenes. The editors then went out onto the web and located what seemed to be the best sites to match the most popular queries.

5.It gained a strong following among experienced web users and techies for the quality and comprehensiveness of its results it continues to sport today.

6.However, being large doesn’t make much of a difference when it comes to popular queries, and Teoma’s won praise for its relevancy since it appeared in 2000.

7.AltaVista opened in December 1995 and for several years was the “Google” of its day, in terms of providing relevant results and having a loyal group of users that loved the service.

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8.Sadly, an attempt to turn AltaVista into a portal site in 1998 saw the company lose track of the importance of search. Over time, relevancy dropped, as did the freshness of AltaVista’s listings and the crawler’s coverage of the web.

9.If you want a lighter-feel than Yahoo but to still have Yahoo’s results, AltaVista is worth considering. Give it a whirl, if you want to try something experimental yet dependable

10. While you can search at the Open Directory site itself, this is not recommended. The site has no “backup” results that kick in should there not be a match in the human-compiled database

IX. Fostering Critical Thinking Skills

Read the text. Find additional material to expand the topic and write a commented essay in Russian on Search Engines and Directories:

Major Search Engines And Directories

http://www.google.com

Voted four times Most Outstanding Search Engine by cybernauts, Google has a well-deserved reputation as the top choice for those searching the web. The crawler-based service provides both comprehensive coverage of the web along with great relevancy. Google has a serious goshwow factor providing the option to find more than web pages, however. Using the search box on the top of the Google home page, you can easily seek out images from across the web, discussions that are taking place on newsgroups, locate news information or perform product searching. Using the More link provides access to humancompiled information from the Open Directory, catalog searching and other services.

Google is also known for the wide range of features it offers, such as cached links that let you “resurrect” dead pages or see older versions of recently changed ones. It offers excellent spell checking, easy access to dictionary definitions, integration of stock quotes, street maps, telephone numbers and more. See Google’s help page for an entire rundown on some of these features. The Google Toolbar has also won a popular following for the easy access it provides to Google and its features directly from the Internet Explorer browser. In addition to Google’s unpaid editorial results, the company also operates its own advertising programs. The cost-per-click AdWords program places ads on Google as well as some of Google’s partners.

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Google was originally a Stanford University project by students Larry Page and Sergey Brin called BackRub. By 1998, the name had been changed to Google, and the project jumped off campus and became the private company Google. It remains privately held today.

http://www.yahoo.com

Yahoo! loves a regular metamorphose. Launched in 1994, Yahoo! was the web’s oldest “directory,” a place where human editors organize web sites into categories. Later Yahoo! made a giant shift to crawl- er-based listings for its main results. The Yahoo! Directory still survives. You’ll notice “category” links below some of the sites lists in response to a keyword search. When offered, these will take you to a list of web sites that have been reviewed and approved by a human editor. In addition to excellent search results, you can use tabs above the search box on the Yahoo! home page to seek images, Yellow Page listings or use Yahoo!’s excellent shopping search engine.

http://www.askjeeves.com

Ask Jeeves initially gained fame in 1998 and 1999 as being the “natural language” search engine that let you search by asking questions and responded with what seemed to be the right answer to everything. In reality, the company had about 100 editors who monitored search logs behind the scenes. The editors then went out onto the web and located what seemed to be the best sites to match the most popular queries. Now the emphasis is less on Natural Language Processing but more on the crawl- er-based search technology. Ask Jeeves offers some popular applications such as: Map search, Movie search, White pages search, Dictionary search, Weather search, Product search, News search, Stock search.

http://www.teoma.com

Teoma is a crawler-based search engine purchased by Ask Jeeves in September 2001. It gained a strong following among experienced web users and techies for the quality and comprehensiveness of its results it continues to sport today. Teoma has a smaller index of the web than its rival crawler-competitors Google and Yahoo. However, being large

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doesn’t make much of a difference when it comes to popular queries, and Teoma’s won praise for its relevancy since it appeared in 2000. Teoma determines results by ranking a site based on its subject-spe- cific popularity (the number of Web pages about the subject that reference this page) as well as its general popularity (the number of all the Webpages that reference this page).

Results are presented in three groups: to the right, Experts’ Links shows collections of links related to the query terms, to the left, Web Pages shows regular results, individual pages that match the query terms (in contrast to the Expert Links pages that don’t provide answers but may lead to pages that do), and at the top under Web Pages Grouped By Topic, the Web Pages and Expert Links are organized into broad categories. Some people also like its “Refine” feature, which offers suggested topics to explore after you do a search. The “Resources” section of results is also unique, pointing users to page that specifically serve as link resources about various topics.

http://www.altavista.com

AltaVista opened in December 1995 and for several years was the “Google” of its day, in terms of providing relevant results and having a loyal group of users that loved the service. Sadly, an attempt to turn AltaVista into a portal site in 1998 saw the company lose track of the importance of search. Over time, relevancy dropped, as did the freshness of AltaVista’s listings and the crawler’s coverage of the web. Today, AltaVista is once again focused on search. Results come from Yahoo, and tabs above the search box let you go beyond web search to find images, MP3/Audio, Video, human category listings and news results. If you want a lighter-feel than Yahoo but to still have Yahoo’s results, AltaVista is worth considering. Give it a whirl, if you want to try something experimental yet dependable.

http://www.looksmart.com

LookSmart is primarily a human-compiled directory of web sites. It gathers its listings in two ways. Commercial sites pay to be listed in its commercial categories, making the service very much like an electronic “Yellow Pages.” However, volunteer editors at the LookSmart-owned Zeal directory also catalog sites into non-commercial categories for free. Though Zeal is a separate web site, its listings are integrated into

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LookSmart’s results. Finally, the real gem at LookSmart can be found via its Articles tab. That provides access to content from thousands of periodicals.

http://dmoz.org/

The Open Directory uses volunteer editors to catalog the web. Formerly known as NewHoo, it was launched in June 1998. While you can search at the Open Directory site itself, this is not recommended. The site has no “backup” results that kick in should there not be a match in the humancompiled database.

In addition, the ranking of sites during keyword searching is poor, while alphabetical ordering is used when you choose to “browse” categories by topic. Instead, to scan the valuable information compiled by the Open Directory, consider using the version offered by Google, the Google Directory. Here, keyword searching uses Google’s refined relevancy algorithms and makes use of link analysis to better propel good pages from the human database to the top. In addition, when viewing sites by category, they will be listed in PageRank order, which means the most popular sites based on analyzing links from across the web will be listed first.

X. Organizing Ideas

Make a concept map on Internet and fill it with basic concepts, associated words and phrases you’ve learned in this unit.

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Biology And Medicine

Unit I

Human Body

I. Getting Started

Read the text “Muscular and Sceletal Systems”. Divide it into several key parts and compose 3-5 questions to the each part. Put your questions to class.

II. Working With Vocabulary

Place the words and phrases below into the “Word“ column and complete the table:

	Word	English	Examples	Russian
		definition	of usage	translation

single-celled protozoan, cilia, organelle, support/locomotion systems, exoskeleton, endoskeleton, hydrostatic skeleton, longitudinal and circular muscles, visceral organs, vertebrate, cartilage, homeostatic, tendon, joint, by-product, axial/appendicular skeleton, metabolism, fontanel, rib cage, humerus, femur, metacarpals and metatarsals, girdle, collar bone, shoulder blade, ligament, biped, oblique muscle, conscious control, gastrointestinal tract, autonomic nervous system.

III. Practising Translation Techniques

Make a written translation of the following text:

Muscular And Skeletal Systems

The single-celled protozoan ancestors of animals had their weight supported by water and were able to move by cilia or other simple organelles. The evolution of large and more complex organisms (animals) necessitated the development of muscular and skeletal systems for support and locomotion. Types of skeletal systems include fluid-

filled body cavities, exoskeletons and internal skeletons.

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Hydrostatic skeletons consist of fluid-filled closed chambers. Internal pressures generated by muscle contractions cause movement as well as maintain the shape of the animals, such as the sea anemone and worms. The sea anemone has one set of longitudinal muscles in the outer layer of the body, and a layer of circular muscles in the inner layer of the body. The anemone can elongate or contract its body by contracting one or the other set of muscles.

Muscles are on the outside of the endoskeleton. Sharks, and rays have skeletons composed entirely of cartilage; other vertebrates have an embryonic cartilage skeleton progressively replaced by bone as they mature and develop. Some areas of the human body, however, retain cartilage in the adult: in joints and flexible structures such as the ribs, trachea, nose and ears.

The skull, vertebral column, and rib cage comprise the axial skeleton. The human skull, or cranium, has a number of individual bones tightly fitted together at immovable joints. At birth many of these joints are not completely sutured together as bone, leading to a number of “soft spots” or fontanels, which do not completely join until the age of 14-18 months. The vertebral column has 33 individual vertebrae separated from each other by a cartilage disk. These disks allow a certain flexibility to the spinal column, and cartilage allows for the flexibility of the rib cage during breathing.

The arms and legs are part of the appendicular skeleton. The upper bones of the limbs are single: humerus (arm) and femur (leg). Below a joint (elbow or knee), both limbs have a pair of bones (radius and ulna in the arms; tibia and fibula in legs) that connect to another joint (wrist or ankle). The carpals makeup the wrist joint; the tarsals are in the ankle joint. Each hand or foot ends in 5 digits composed of metacarpals (hands) or metatarsals (feet). Limbs are connected to the rest of the skeleton by collections of bones known as girdles. The pectoral girdle

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consists of the clavicle (collar bone) and scapula (shoulder blade). The humerus is joined to the pectoral girdle at a joint and is held in place by muscles and ligaments. A dislocated shoulder occurs when the end of the humerus slips out of the socket of the scapula, stretching ligaments and muscles. The pelvic girdle consists of two hipbones that form a hollow cavity, the pelvis. The pelvic girdle in land animals transfers the weight of the body to the legs and feet. Pelvic girdles in fish, which have their weight supported by water, are primitive. pelvic girdles in bipeds are recognizable different from those or quadrupeds.

In the body, there are three types of muscle: skeletal (striated), smooth, and cardiac. Skeletal muscle, attached to bones, is responsible for skeletal movements. The peripheral portion of the central nervous system (CNS) controls the skeletal muscles. Thus, these muscles are under conscious, or voluntary, control. The basic unit is the muscle fiber with many nuclei. These muscle fibers are striated (having transverse streaks) and each acts independently of neighboring muscle fibers.

Smooth muscle, found in the walls of the hollow internal organs such as the gastrointestinal tract, etc., is under control of the autonomic nervous system. Smooth muscle cannot be controlled consciously and thus acts involuntarily. The non-striated (smooth) muscle cell is spindle-shaped and has one central nucleus. Smooth muscle contracts slowly and rhythmically.

Cardiac muscle, found in the walls of the heart, is also under control of the autonomic nervous system. The cardiac muscle cell has one central

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nucleus, like smooth muscle, but it also is striated, like skeletal muscle. The cardiac muscle cell is rectangular in shape. The contraction of cardiac muscle is involuntary, strong, and rhythmical.

The musculoskeletal system plays an important homeostatic role: muscles, attached to bones or internal organs and blood vessels, are responsible for movement. Besides, the skeletal muscles are continually making fine adjustments that hold the body in stationary positions and prevent disturbances of the equilibrium of the body generally. The tendons of many muscles extend over joints and in this way contribute to joint stability, which is is particularly evident in the knee and shoulder joints. Heat production, to maintain body temperature, is an important by-product of muscle metabolism. Nearly 85 percent of the heat produced in the body is the result of muscle contraction. There are more than 600 muscles in the body, which together account for about 40 percent of a person’s weight.

IV. Knowing Ins And Outs

Most skeletal muscle names describe some feature of the muscle, for example, the name of Latissimus Dorsi, the broadest muscle of the back, was coined from Latin latissimus (superlative of latus, wide) + Latin dors (genitive of dorsum, back).

Study the table below and make a list of muscle names associated with the given Latin roots and affixes. Translate the list into Russian.

Characteristics	Latin roots and affixes
Size	vastus (huge), maximus (large), longus (long),
	minimus (small), brevis (short)
Shape	deltoid (triangular), rhomboid (like a rhombus),
	latissimus (wide), trapezius (like a trapezoid),
	teres (round)
Direction of fibers	rectus (straight), transverse (across), oblique
	(diagonally), orbicularis (circular)
Location	pectoralis (chest), brachii (arm), supra- (above),
	infra- (below), sub- (under or beneath), lateralis
	(lateral)
Number of origins	bi- (two), tri- (three), quadri- (four)
Action	ab- (away), ad- (towards), extens- (to stretch
	out), duc- (to lead), rota- (in a circle), flex- (to
	bend),
	lev- (to lift)

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