You should spend about 20 minutes on Questions 1-13> which are based on
Reading Passage 1 below.
The CT Scanner
A
The computed tomography scanner, better known as the CT scanner, was originally
designed to provide cross-sectional images of the brain. The word tomography
comes from the Greek word tomos, meaning “section,” and graphic
meaning “picture.” Godfrey Hounsfield developed the technique in 1972 and
was later knighted and awarded the Nobel Peace Prize for his contribution to the
medical field. Within four years of this development, CT scans, also called CAT
scans (computed axial tomography), were restructured, allowing technicians to
scan the entire body for evidence of tumors, injuries, and other abnormalities.
Rather than taking a single picture as in an X ray, a CT scanner sends several
beams into an area and takes photographs from many different angles.
B
While the original CT scans took Hounsfield several hours to reconstruct into a
useful image, today’s machines can produce an in-depth image in a fraction of a
second. Creating a scanner that could produce images at a faster rate was crucial in
the development of tomography, as it reduced the degree of distortion in an image
caused when patients breathed and moved. As well as providing images with
better resolution, today’s scanners also provide more comfort for the patient.
C
During a CT scan, a patient must lie still on a special table while the radiology
technician locates the specific area that needs to be photographed. The table
slides into a round tunnel (gantry), where it can be rotated or moved forward
and backward in order to obtain the necessary view. Inside the donut-shaped1
machine, a number of X rays are taken, each producing a small slice of the image
that doctors require. When passing through dense tissue such as a bone, the
X-ray beams are weak and appear white in the CT images. Tissues such as those
found in the brain are less dense and appear gray. Images that appear black
denote organs such as lungs or others that can fill with air.
D
The CT scanner is made up of several computer systems, including the host
computer, which organizes2 the entire process. One of the computers converts
the raw data into an image, while another allows the technician to control the
rotation of the gantry. After the information is processed, it is displayed on a
monitor for radiologists and physicians to analyze.3 The information is also saved
and printed to keep in a doctor’s records and to share and discuss with patients
and their family members.
E
Physicians order CT scans for a number of different reasons, including searching
for and assessing tumors, cysts, kidney stones, and bone injuries. Without this
technology, surgeons would have to perform many needless and costly operations.
Brain, chest, and abdominal CT scans are the most common, though
physicians also rely on the CT scanner to guide their needles while draining an
abscess or performing a biopsy. Most emergency or shock-treatment centers contain
a CT scanner in order to assess trauma victims. CT scans can pinpoint internal
bleeding both in the brain and throughout the body.
F
In many cases, a patient must be given a contrast material before undergoing a
CT scan. During “dynamic CT scanning,” iodine dye is either injected into the blood
or added to a drink that the patient must ingest approximately forty-five minutes
before entering the scanner. The liquid X-ray dye makes it easier to see the organs
and blood vessels when the pictures are developed. The intravenous contrast material
is typically used for chest or pelvic scans, while oral-contrast material is used for
abdominal scans. In some cases, physicians request that pictures be taken both
before and after the contrast material enters the patient’s body. Patients who
receive contrast material in the arm often report feeling a warm sensation, and in
rare cases an allergic reaction occurs. Contrast material causes water loss and is
avoided when scanning patients who suffer from kidney failure.
G
The danger of radiation exposure caused by X-ray beams is generally considered
minimal compared to the benefits that a CT scan can provide. In many cases,
especially in the detection of tumors and internal bleeding, CT scans provide
information that can save a person’s life. Full-body scanning, which is saved for
serious conditions such as coronary artery disease, remains a controversial procedure
as prolonged exposure to radiation is linked to cancer. Pregnant women are
excluded from receiving CT scans, as the X rays can be harmful to the fetus.
When pregnant woman require an evaluation, most physicians favor using other
procedures such as an ultrasound or an MRI.
You should spend about 20 minutes on Questions 1—13, which are based on
Reading Passage 1 below.
Questions 1 -7
The following reading passage has seven sections, A-G. Choose the correct heading
for each section from the list of headings below. Write the correct number, i—x, on
lines 1—7 on your answer sheet. There are more headings than sections, so you will
not use them all.
LIST OF HEADINGS
i Scanning the Brain and Chest
ii The Role of Computers
iii The CT Scan Is Invented
iv The High Cost of CT Scans
v Risk Associated wtih CT Scans
vi Emergency Room Care
vii Faster and More Comfortable
viii How Doctors Use CT Scans
ix The Patient Is Photographed
x Enhancing Scan Images with Dyes>
1 Section A __1__
2 Section B __2__
3 Section C __3__
4 Section D __4__
5 Section E __5__
6 Section F __6__
7 Section G __7__
Questions 8—10
Which of the following are facts about the original CT scanner mentioned in the
passage? Choose THREE answers from the list below and write the correct letters,
A-F, on lines 8—10 on your answer sheet.
A It made it difficult for patients to breathe.
B It was created to take pictures of the brain.
C It was much bigger than current CT scanners.
D It was developed in 1972.
E It took several hours to produce a completed image.
F It produced images in color.
8. __8__
9. __9__
10. __10__
Questions 11-13
Which o f the following are facts about contrast materials used for CT scans mentioned
in the passage? Choose THREE answers from the list below and write the
correct letters, A-F, on lines 11—13 on your answer sheet.
A They are bright in color.
B They can be given by injection.
C They have a bitter taste.
D They might cause a feeling of warmth in the arm.
E They are administered only by a specially trained technician.
F They may cause allergies in a few patients.
11. __11__
12. __12__
13. __13__
You should spend about 20 minutes on Questions 14—26, which are rnsea on
Reading Passage 2
Nineteenth-Century Paperback Literature
A publishing craze that hit both America and England from the mid- to late
nineteenth century attracted the readership of the semiliterate working class.
In America, dime novels typically centered on tales of the American
Revolution and the Wild West, while British penny bloods (later called penny
dreadfuls) told serial tales of horror or fictionalized1 versions of true crimes.
These paperback novels were sold at newsstands and dry goods stores and succeeded
in opening up the publishing market for both writers and readers. The
industrial revolution facilitated the growth of literacy, making it easier to print
and transport publications in large quantities, thus providing inexpensive
entertainment for the masses.
Though Johann Gutenberg’s printing press was designed in the fifteenth
century, it was not until after the first newspapers began circulating in the eighteenth
century that it became a profitable invention. Throughout the nineteenth
century, commoners in England were becoming educated through normal
schools, church schools, and mutual instruction classes, and by the 1830s,
approximately 75 percent of the working class had learned to read. In 1870, the
Forster Education Act made elementary education mandatory for all children.
Though few children’s books were available, penny dreadfuls were highly accessible,
especially to male youths who created clubs in order to pool their money
and start their own libraries. Similar to reading a newspaper, dime novels and
penny dreadfuls were meant to be read quickly and discarded, unlike the hardbound
high literature that was written in volumes and published for the elite.
Struggling authors, many of whom had limited writing and storytelling skills,
suddenly found an audience desperate to read their work. When the first typewriter
became available in the 1870s, authors were able to maximize2 their output.
Successful authors, some of whom wrote over 50,000 words a month, were
able to earn a decent living at a penny per word.
From the 1830s to 1850s, penny bloods featured tales of gore that often
depicted the upper class as corrupt. One of the most beloved characters from the
penny blood serials was Sweeney Todd. In the original story, String o f Pearls: A
Romance, published in 1846, Sweeney Todd was a demon barber who used his
razor to torture his victims before turning them into meat pies. In 1847, hackplaywright
George Dibdin Pitt adapted Thomas Prest’s story for the stage,
renaming it The String o f Pearls: The Fiend o f Fleet Street. With no copyright
laws, authors were always at risk of having their ideas pilfered. Pitt’s play was
released again one year later at one of London’s “bloodbath” theaters1 under
the name Founded on Fact. The Sweeney Todd story also made its way into
musicals and comedies. Controversy still exists over whether Thomas Prest’s
character was based on a real person. No records of a barber shop on Fleet
Street, or a barber named Sweeney Todd have been found, though Thomas
Prest was known for getting his inspiration from “The Old Bailey” of the
London Times, a section devoted to real-life horror stories.
Despite the warning from Lord Shaftsbury that the paperback literature was
seducing middle-class society into an unproductive life of evil, the penny
bloods grew in popularity. They provided a literary voice for commoners at an
affordable price. Eventually, penny bloods became known as penny dreadfuls
and began to focus more on adventure than horror.
In 1860, Beadle and Adams was the first firm in the United States to publish
a title that would be categorized2 as a dime novel. Malaeska: The Indian
Wife o f the White Hunter, by Anne Stephens, had originally been published
twenty years earlier as a series in a magazine. In novel form, approximately
300,000 copies of the story were sold in the first year, paving the way for the
new fad in America. Many dime novels were written as serials with recurring
characters, such as Deadwood Dick, Commander Cody, and Wild Bill.
Originally, the paperbacks were intended for railroad travelers; however, during
the Civil War, soldiers quickly became the most avid dime novel readers.
Beadle dime novels became so popular that the company had to build a factory
of hack writers to mass produce them. As urbanization3 spread, stories
of the Wild West were in less demand, and tales of urban outlaws became
popular. At that time, dime novels were chosen for their illustrated covers
rather than their sensational stories and characters. Despite their popularity,
by the late 1880s dry goods stores were so full of unsold books that prices
dropped to less than five cents per copy. Many titles that could still not sell
were given away or destroyed. The International Copyright Law, passed by
Congress in 1890, required publishers to pay royalties to foreign authors.
Selling at less than five cents a copy, the paperback industry was doomed
until the arrival of pulp paper.
Questions 14—19
Which o f the characteristics below belongs to which type o f literature? On lines 14—19 on
answer sheet write:
A. if it is characteristic of penny bloods
B. if it is characteristic of dime novels
C. if it is characteristic of both penny bloods and dime novels
14 They were popular in America. __14__
15 They were popular in Britain. __15__
16 They showed members of the upper class as corrupt. __16__
17 They were inexpensive. __17__
18 They featured tales of the Wild West. __18__
19 They were popular among members of the working class. __19__
Questions 20-23
Match each year with the event that occurred during that year. Choose the correct
event, A-F, from the box below and write the correct letter on lines 20—23 on your
answer sheet. There are more events than years, so you will not use them all.
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20 1870 __20__
21 1846 __21__
22 1860 __22__
23 1890 __23__
Questions 24—27
Do the following statements agree with the information in the reading passage? On
lines 24—27 on your answer sheet write:
YES if the statement agrees with the information
NO if the statement contradicts the information
NOT GIVEN If there is no information on this in the passage
24 The literacy rate in England rose in the nineteenth century. __24__
25 Children’s books were popular in the nineteenth century. __25__
26 Most people agree that Sweeney Todd was based on a real person. __26__
27 Dime novels were popular among Civil War soldiers. __27__
You should spend about 20 minutes on Questions 27—40> which are based on
Reading Passage 3 below.
Cosmic Black Holes
In 1687, the English scientist Isaac Newton published his monumental work,
Philosophiae Naturalis Principia Mathematica (Mathematical Principles o f Natural
Philosophy), containing his theory of gravitation and the mathematics to support
it. In essence, Newton’s law of gravitation stated that the gravitational force
between two objects, for example, two astronomical bodies, is directly proportional
to their masses. Astronomers found that it accurately predicted all the
observable data that science at that time was able to collect, with one exception—
a very slight variation in the orbit of the planet Mercury around the sun.
It was 228 years before anyone was able to offer a refinement of Newton’s law that
accounted for the shape of Mercury’s orbit. In 1915, Albert Einstein’s general theory
of relativity was published. Using the equations of general relativity, he calculated
the shape of Mercury’s orbit. The results predicted astronomical observations
exactly and provided the first proof of his theory. Expressing it very simplistically,
the general theory of relativity presumes that both matter and energy can distort
space—time and cause it to curve. What we commonly call gravity is in fact the effect
of that curvature.
Among other phenomena, Einstein’s theory predicted the existence of black
holes, although initially he had doubts about their existence. Black holes are areas
in space where the gravitational field is so strong that nothing can escape
them. Because of the immense gravitational pull, they consume all the light
that comes near them, and thus they are “black.” In fact, neither emitting nor
reflecting light, they are invisible. Due to this, they can be studied only by
inference based on observations of their effect on the matter—both stars and
gases1—around them and by computer simulation. In particular, when gases
are being pulled into a black hole, they can reach temperatures up to 1,000
times the heat of the sun and become an intensely glowing source of X rays.
Surrounding each black hole is an “event horizon,” which defines the area
over which the gravitational force of the black hole operates. Anything passing
over the lip of the event horizon is pulled into the black hole. Because
observations of event horizons are difficult due to their relatively small size,
even less is known about them than about black holes themselves.
Black holes exist in three sizes. Compact ones, called star-mass black holes
and which have been known to exist for some time, are believed to be the result
of the death of a single star. When a star has consumed itself to the point that it
no longer has the energy to support its mass, the core collapses and forms a black
hole. Shock waves then bounce out, causing the shell of the star to explode. In
a way that is not yet understood, the black hole may then reenergize2 and create
multiple explosions within the first few minutes of its existence. So-called supermassive
black holes, also well documented, contain the mass of millions or even
billions of stars. And just recently one intermediate black hole, with about 500
times the mass of the sun, has been discovered. Scientists have postulated that
the intermediate black hole may provide a “missing link” in understanding the
evolution of black holes.
Current scientific data suggest that black holes are fairly common and lie at
the center of most galaxies. Based on indirect evidence gained using X-ray telescopes,
thousands of black holes have been located in our galaxy and beyond.
The black hole at the center of the Milky Way, known as Sagittarius A* (pronounced
“A-star”), is a supermassive one, containing roughly four million
times the mass of our sun. Astronomers suggest that orbiting around
Sagittarius A*, 26,000 light years from Earth, may be as many as tens of thousands
of smaller black holes. One possible theory to explain this is that a
process called “dynamical friction” is causing stellar black holes to sink toward
the center of the galaxy.
It is thought that the first black holes came into existence not long after the
big bang. Newly created clouds of gases slowly coalesced into the first stars. As
these early stars collapsed, they gave rise to the first black holes. A number of
theories proposed that the first black holes were essentially “seeds,” which then
gravitationally attracted and consumed enormous quantities of matter found in
adjacent gas clouds and dust. This allowed them to grow into the super-massive
black holes that now sit in the centers of galaxies. However, a new computer
simulation proposes that such growth was minimal. When the simulated star
collapsed and formed a black hole, there was very little matter anywhere near the
black hole’s event horizon. Being in essence “starved,” it grew by less than 1 percent
over the course of its first hundred million years. The new simulations do
not definitively invalidate the seed theory, but they make it far less likely. On
the other hand, it is known that black holes a billion times more massive than
our sun did exist in the early universe. Researchers have yet to discover how
these super-massive black holes were formed in such a short time, and the origin
of these giants poses one of the most fundamental questions in astrophysics.
It has become practically a hallmark of the research on black holes that with
each new study, more is known, more theories are generated, and yet more
questions are raised than answered.
Questions 28—34
Complete each sentence with the correct ending, A—N, below.
Write the correct letter, A—N, on lines 28—34 on your answer sheet.
A by observing the matter around them.
B suggested the presence of black holes in outer space.
C when a single star collapses.
D difficult to study.
E barely visible light.
F an inescapable gravitational pull.
G did not apply to most astronomical bodies.
H by direct observation.
I could not explain Mercury’s path around the sun.
J caused doubt about the existence of black holes.
K lose visibility.
L become very hot.
M with large event horizons.
N at the center of each black hole.
28 Newton’s law of gravitation __28__
29 Einstein’s theory of relativity __29__
30 We define black holes as areas that have __30__
31 Scientists study black holes __31__
32 Gases that are pulled into a black hole __32__
33 Event horizons are __33__
34 Compact black holes occur __34__
Questions 35 and 3 6
Choose the correct letter, A, B, or C, in boxes 35 and 3 6 on your answer sheet.
35 Black holes can be found
A only in the Milky Way.
B in most galaxies.
C close to the sun.
__35__
36 Sagittarius A* is
A a black hole located 26,000 light years from Earth.
B one of thousands of black holes orbiting Earth.
C a well-known compact black hole.
__36__
Questions 37-40
Do the following statements agree with the information given it
lines 37—40 on your answer sheet, write:
TRUE if the statement agrees with the information
FALSE if the statement contradicts with the information
NOT GIVEN if there is no information on this
37 It is not certain when the big bang occurred. __37__
38 According to the “seed” theory, the first black holes eventually became supermassive
black holes. __38__
39 The “seed” theory has been proven true by computer simulation. __39__
40 The black holes that existed in the early universe were all compact black holes. __40__
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