You
should spend about 20 minutes on Questions 1-12, which are based on Reading Passage 1 below.
The potential to sniff
out disease
The fact diseases have a
smell comes as no surprise - but finding someone or something that can detect
them at an early stage could hold huge potential for medicine.
Breath,
bodily odours and urine are all amazingly revealing about general health. Even
the humble cold can give off an odour, thanks to the thick bacteria-ridden
mucus that ends up in the back of the throat. The signs are not apparent to
everyone - but some super-smellers are very sensitive to the odours. Joy Milne,
for example, noticed her husband's smell had changed shortly before he was
diagnosed with Parkinson's disease.
Humans
can detect nearly 10,000 different smells. Formed by chemicals in the air, they
are absorbed by little hairs, made of extremely sensitive nerve fibres, hanging
from the nose's olfactory receptors. And the human sense of smell is 10,000
times more sensitive than the sense of taste. But dogs, as the old joke might
have had it, smell even better.
Their
ability to detect four times as many odours as humans makes them a potential
early warning system for a range of diseases. Research suggesting dogs' could
sniff out cancers, for example, was first published about 10 years ago. And
there have been many tales of dogs repeatedly sniffing an area of their owner's
body, only for it to turn out to be hiding a tumour.
What
they are smelling are the "volatile molecules" given off by cells
when they become cancerous. Some studies suggest dogs can be 93% accurate.
Others suggest they can detect very small tumours before clinical tests can.
And yet more studies have produced mixed results.
Does cancer smell?
At
Milton Keynes University Hospital, a small team has recently begun to collect
human urine samples to test dogs' ability to detect the smell of prostate
cancer. The patients had symptoms such as difficulty urinating or a change in
flow, which could turn out to be prostate, bladder or liver cancer.
Rowena
Fletcher, head of research and development at the hospital, says the role of
the dogs - which have been trained by Medical Detection Dogs - is to pick out
samples that smell of cancer. Further down the line, a clinical test will show
if the dogs' diagnosis is correct. She says the potential for using dogs in
this way is far-reaching - even if it is not practical to have a dog in every
surgery.
"We
hope one day that there could be an electronic machine on every GP's desk which
could test a urine sample for diseases by smelling it," she says.
"But first we need to pick up the pattern of what the dogs are
smelling."
And
that's the key. Dogs can't tell us what their noses are detecting, but
scientists believe that different cancers could produce different smells,
although some might also be very similar.
Electronic noses
Lab
tests to understand what these highly-trained dogs are smelling could then
inform the development of 'electronic noses' to detect the same molecules.
These might then give rise to better diagnostic tests in the future. The
potential for using smell to test for a wide range of diseases is huge, Ms
Fletcher says.
Bacteria,
cancers and chronic diseases could all have their own odour - which may be
imperceptible to only the most sensitive humans, but obvious to dogs. It may be
possible in the future to use disease odours as the basis for a national
screening programme or to test everybody at risk of a certain cancer in a
particular age group.
However,
there are fewer than 20 dogs in the UK trained to detect cancer at present.
Training more will take more funding and time. On the positive side, all dogs
are eligible to be trained provided they are keen on searching and hunting.
Whatever their breed or size, it's our four-legged friend's astounding sense of
smell which could unlock a whole new way of detecting human diseases.
Questions 1-5
Do the following
statements agree with the information in the IELTS reading text?
In boxes 1-5 on your answer sheet, write
TRUE
if the statement agrees with the information
FALSE
if the statement contradicts the information
NOT GIVEN
if there is no information on this
1. You can have a
specific smell even due to simple cold.
2. Human sense of
taste is 10,000 less sensetive than human sense of smell.
3. Dogs and cats can sniff
out different diseases.
4. Doctors believe that different
cancers might have the same specific smell.
5. There are more
than 20 dogs in the UK trained to detect cancer.
Questions 6-9
Choose the correct
letter, A, B, C or D.
Write the correct letter
in boxes 6-9 on your answer sheet.
6. All the studies suggest
that dogs:
- Can be 93% accurate
- Can detect very
small tumours
- Can't detect
tumours at all
- Different studies
have shown different results
7. What scientists give
dogs to detect cancer?
- Urine samples
- Bacterias
- Different odours
- Nothing
8. What's an electronic
nose?
- A specific tool for dogs
- A gadget to diagnose
diseases
- A recovery tool for ill
patients
- An artificial nose
9. The main objective of
this passage is to:
- Bring awareness to the
cancer problem
- Show us how good
dogs are at detecting cancer
- Show us how important it
can be to be able to diagnose a disease by an odour
- Tell us about new
technologies
Questions 10-12
Complete the sentences
below.
Write NO MORE THAN TWO WORDS from the passage for each answer.
Write your answers in
boxes 10-12 on your answer
sheet.
10. Scientists
hope that one day an will be on every desk.
11. Electronic
nose would help to detect the .
12. Dogs can a
new way of diagnosing diseases.
You
should spend about 20 minutes on Questions 13-26, which are based on Reading Passage 2 below.
Trash Talk
Sorting through a
mountain of pottery to track the Roman oil trade
(A) In the middle of Rome’s trendiest neighborhood, surrounded by
sushi restaurants and nightclubs with names like Rodeo Steakhouse and Love
Story, sits the ancient world’s biggest garbage dump—a 150-foot-tall mountain
of discarded Roman amphoras, the shipping drums of the ancient world. It takes
about 20 minutes to walk around Monte Testaccio, from the Latin testa and
Italian cocci, both meaning “potsherd.” But despite its size—almost a mile in
circumference—it’s easy to walk by and not really notice unless you are headed
for some excellent pizza at Velavevodetto, a restaurant literally stuck into
the mountain’s side. Most local residents don’t know what’s underneath the
grass, dust, and scattering of trees. Monte Testaccio looks like a big hill,
and in Rome people are accustomed to hills.
(B) Although a garbage dump may lack the attraction of the Forum or
Colosseum, I have come to Rome to meet the team excavating Monte Testaccio and
to learn how scholars are using its evidence to understand the ancient Roman
economy. As the modern global economy depends on light sweet crude, so too the
ancient Romans depended on oil—olive oil. And for more than 250 years, from at
least the first century A.D., an enormous number of amphoras filled with olive
oil came by ship from the Roman provinces into the city itself, where they were
unloaded, emptied, and then taken to Monte Testaccio and thrown away. In the
absence of written records or literature on the subject, studying these
amphoras is the best way to answer some of the most vexing questions concerning
the Roman economy—How did it operate? How much control did the emperor exert
over it? Which sectors were supported by the state and which operated in a free
market environment or in the private sector?
(C) Monte Testaccio stands near the Tiber River in what was ancient
Rome’s commercial district. Many types of imported foodstuffs, including oil,
were brought into the city and then stored for later distribution in the large
warehouses that lined the river. So, professor, just how many amphoras are
there?” I ask José Remesal of the University of Barcelona, co-director of the
Monte Testaccio excavations. It’s the same question that must occur to everyone
who visits the site when they realize that the crunching sounds their footfalls
make are not from walking on fallen leaves, but on pieces of amphoras. (Don’t
worry, even the small pieces are very sturdy.) Remesal replies in his deep
baritone, “Something like 25 million complete ones. Of course, it’s difficult
to be exact,” he adds with a typical Mediterranean shrug. I, for one, find it
hard to believe that the whole mountain is made of amphoras without any soil or
rubble. Seeing the incredulous look on my face as I peer down into a
10-foot-deep trench, Remesal says, “Yes, it’s really only amphoras.” I can’t
imagine another site in the world where archaeologists find so much—about a ton
of pottery every day. On most Mediterranean excavations, pottery washing is an
activity reserved for blisteringly hot afternoons when digging is impossible.
Here, it is the only activity for most of Remesal’s team, an international group
of specialists and students from Spain and the United States. During each
year’s two-week field season, they wash and sort thousands of amphoras handles,
bodies, shoulders, necks, and tops, counting and cataloguing, and always
looking for stamped names, painted names, and numbers that tell each amphora’s
story.
(D) Although scholars worked at Monte Testaccio beginning in the
late 19th century, it’s only within the past 30 years that they have embraced
the role amphoras can play in understanding the nature of the Roman imperial
economy. According to Remesal, the main challenge archaeologists and economic
historians face is the lack of “serial documentation,” that is, documents for
consecutive years that reflect a true chronology. This is what makes Monte Testaccio
a unique record of Roman commerce and provides a vast amount of datable
evidence in a clear and unambiguous sequence. “There’s no other place where you
can study economic history, food production and distribution, and how the state
controlled the transport of a product,” Remesal says. “It’s really remarkable.”
Questions 13-16
Reading Passage 2 has
four paragraphs A-D. Which paragraph
contains what information? Write the correct letter, A-D, in boxes 13-16 on your answer sheet.
13. Questions about the Roman economy
14. A unique feature
15. Description
of the dump
16. Dialogue
with a professor
Questions 17–21
Do the following
statements agree with the information given in Reading Passage 2?
In boxes 17–21 on your answer sheet, write
TRUE
if the statement agrees with the information
FALSE
if the statement contradicts the information
NOT GIVEN
if there is no information on this
17. World’s
biggest garbage dump is surrounded by restaurants and nightclubs.
18. The
garbage dump is as popular as the Colosseum in Rome.
19. Ancient
Roman economy depended on oil.
20. There
is no information on how many amphoras are there.
21. Remesal
says that Monte Testaccio is a great place to study economics.
Questions 22–26
Complete the sentences
below.
Write NO MORE THAN THREE WORDS from the passage for each answer.
Write your answers in
boxes 22–26 on your answer sheet.
22. It
is unknown for what’s underneath the grass, dust,
and scattering of trees.
23. Monte
Testaccio stands near the ancient Rome’s .
24. Remesal
doesn't believe that the whole mountain is made of without
any soil or rubble.
25. Remesal’s
team washes and sorts thousands of amphoras each year’s two-week .
26. started
working at Monte Testaccio in the late 19th century.
You
should spend about 20 minutes on Questions 27-40, which are based on Reading Passage 3 below.
Mysterious Dark Matter
May Not Always Have Been Dark
Dark matter particles may have interacted
extensively with normal matter long ago, when the universe was very hot, a new
study suggests. The nature of dark matter is currently one of the
greatest mysteries in science. The invisible substance — which is detectable
via its gravitational influence on "normal" matter - is thought to
make up five-sixths of all matter in the universe.
Astronomers
began suspecting the existence of dark matter when they noticed the cosmos
seemed to possess more mass than stars could account for. For example, stars
circle the center of the Milky Way so fast that they should overcome the
gravitational pull of the galaxy's core and zoom into the intergalactic void.
Most scientists think dark matter provides the gravity that helps hold these
stars back. Astronomers know more about what dark matter is not than what it
actually is.
Scientists
have mostly ruled out all known ordinary materials as candidates for dark
matter. The consensus so far is that this missing mass is made up of new
species of particles that interact only very weakly with ordinary matter. One
potential clue about the nature of dark matter has to do with the fact that
it's five times more abundant than normal matter, researchers said.
"This
may seem a lot, and it is, but if dark and ordinary matter were generated in a
completely independent way, then this number is puzzling," said study
co-author Pavlos Vranas, a particle physicist at Lawrence Livermore National
Laboratory in Livermore, California. "Instead of five, it could have been
a million or a billion. Why five?" The researchers suggest a possible
solution to this puzzle: Dark matter particles once interacted often with
normal matter, even though they barely do so now. "This may have happened
in the early universe, when the temperature was very high — so high that
both ordinary and dark matter were 'melted' in a plasma state made up of their
ingredients".
The
protons and neutrons making up atomic nuclei are themselves each made up of a
trio of particles known as quarks. The researchers suggest dark matter is
also made of a composite "stealth" particle, which is composed of a
quartet of component particles and is difficult to detect (like a stealth
airplane). The scientists' supercomputer simulations suggest these composite
particles may have masses ranging up to more than 200 billion electron-volts,
which is about 213 times a proton's mass. Quarks each possess fractional
electrical charges of positive or negative one-third or two-thirds. In protons,
these add up to a positive charge, while in neutrons, the result is a neutral
charge. Quarks are confined within protons and neutrons by the so-called
"strong interaction."
The
researchers suggest that the component particles making up stealth dark matter
particles each have a fractional charge of positive or negative one-half, held
together by a "dark form" of the strong interaction. Stealth dark
matter particles themselves would only have a neutral charge, leading them to
interact very weakly at best with ordinary matter, light, electric fields and
magnetic fields. The researchers suggest that at the extremely high
temperatures seen in the newborn universe, the electrically charged
components of stealth dark matter particles could have interacted with ordinary
matter. However, once the universe cooled, a new, powerful and as yet unknown force
might have bound these component particles together tightly to form
electrically neutral composites. Stealth dark matter particles should be stable
— not decaying over eons, if at all, much like protons. However, the
researchers suggest the components making up stealth dark matter particles can
form different unstable composites that decay shortly after their creation.
"For example, one could have composite particles made out of just two
component particles," Vranas said.
These
unstable particles might have masses of about 100 billion electron-volts or
more, and could be created by particle accelerators such as the Large
Hadron Collider (LHC) beneath the France-Switzerland border. They could
also have an electric charge and be visible to particle detectors, Vranas said.
Experiments at the LHC, or sensors designed to spot rare instances of dark
matter colliding with ordinary matter, "may soon find evidence of, or rule
out, this new stealth dark matter theory," Vranas said in a
statement. If stealth dark matter exists, future research can investigate
whether there are any effects it might have on the cosmos.
"Are
there any signals in the sky that telescopes may find?" Vranas said.
"In order to answer these questions, our calculations will require larger
supercomputing resources. Fortunately, supercomputing development is
progressing fast towards higher computational speeds." The scientists, the
Lattice Strong Dynamics Collaboration, will detail their findings in an
upcoming issue of the journal Physical Review Letters.
Questions 27-34
Complete
the sentences below.
Write NO MORE THAN TWO WORDS from the passage for each answer.
Write
your answers in boxes 27-34 on your answer sheet.
27. One of the greatest mysteries in science is the nature of
the .
28. All known material have been mostly as
candidates for dark matter.
29. Dark matter is a lot more than
normal matter.
30. Due to high temperature, both ordinary and dark matter were
'melted' in a .
31. It is confirmed that quarks are within protons and neutrons
by .
32. It is suggested that stealth dark matter particle would only
have a .
33. Experiments at the LHC may soon find of
the new stealth dark matter theory.
34. To answer questions we require resources .
Questions 35-39
Do
the following statements agree with the information given in Reading Passage 3?
In
boxes 35–39 on your answer sheet, write
TRUE
if the statement agrees with the information
FALSE
if the statement contradicts the information
NOT GIVEN
if there is no information on this
35. The nature of dark matter is a mystery.
36. It is likely that dark matter consists of ordinary
materials.
37. Quarks have neither positive nor negative
charge.
38. Protons are not stable.
39. Dark matter has a serious impact on the cosmos.
Question 40
Choose
the correct letter, A, B, C or D.
40. Passage 3 is:
- a
scientific article
- a
sci-fi article
- a
short sketch
- an
article from a magazine
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