READING PRACTICE 94

PASSAGE 1

Crisis! freshwater
A. As in New Delhi and Phoenix, policymakers worldwide wield great power over how water resources and
managed. Wise use of such power will become increasingly important as the years go by because the world’s
demand for freshwater is currently overtaking its ready supply in many places, and this situation shows no sign
of abating.
B. That the problem is well-known makes it no less disturbing: today one out of six people, more than a billion,
suffer inadequate access to safe freshwater. By 2025, according to data released by the United Nations, the
freshwater resources of more than half the countries across the globe will undergo either stress- for example,
when people increasingly demand more water than is available or safe for use-or outright shortages. By mid-
century, as much as three-quarters of the earth’s population could face scarcities of freshwater.
C. Scientists expect water scarcity to become more common in large part because the world’s population is
rising and many people are getting richer (thus expanding demand) and because global climate change is
exacerbating aridity and reducing supply in many regions. What is more, many water sources are threatened
by faulty waste disposal, releases of industrial pollutants, fertilizer runoff, and coastal influxes of saltwater into
aquifers as groundwater is depleted.
D. Because lack of access to water can lead to starvation, disease, political instability, and even armed conflict,
failure to take action can have broad and grave consequences. Fortunately, to a great extent, the technologies
and policy tools required to conserve existing freshwater and to secure more of it are known among which
several seem particularly effective. What is needed now is action. Governments and authorities at every level
have to formulate and execute plans for implementing the political, economic, and technological measures that
can ensure water security now and in the coming decades.
E. The world’s water problems require, as a start, an understanding of how much freshwater each person
requires, along with knowledge of the factors that impede supply and increase demand in different parts of the
world. Main Falkenmark of the Stockholm International Water Institute and other experts estimate that, on
average, each person on the earth needs a minimum of 1000 cubic meters (m3) of water. The minimum water
each person requires for drinking, hygiene, and growing food. The volume is equivalent to two-fifths of an
Olympic-size swimming pool.
F. Much of the Americas and northern Eurasia enjoy abundant water supplies. But several regions are beset
by greater or lesser degrees of “physical” scarcity-whereby demand exceeds local availability. Other areas,
among them Central Africa, parts of the Indian subcontinent, and Southeast Asia contend with “economic”
water scarcity limit access even though sufficient supplies are available.
G. More than half of the precipitation that falls on land is never available for capture or storage because it
evaporates from the ground or transpires from plants; this fraction is called blue-water sources-rivers, lakes,
wetlands, and aquifers-that people can tap directly. Farm irrigation from these free-flowing bodies is the
biggest single human use of freshwater resources, but the intense local demand they create often drains the
surroundings of ready supplies.
H. Lots of water, but not always where it is needed one hundred and ten thousand cubic kilometers of
precipitation, nearly 10 times the volume of Lake Superior, falls from the sky onto the earth’s land surface
every year. This huge quantity would easily fulfill the requirements of everyone on the planet if the water
arrived where and when people needed it. But much of it cannot be captured (top), and the rest is disturbed
unevenly (bottom). Green water (61.1% of total precipitation): absorbed by soil and plants, then released back
into the air: unavailable for withdrawal. Bluewater (38.8% of total precipitation): collected in rivers, lakes,
wetlands, and groundwater: available for withdrawal before it evaporates or reaches the ocean. These figures
may not add up to 100% because of rounding. Only 1.5% is directly used by people.
I. Waters run away in tremendous wildfires in recent years. The economic actors had all taken their share
reasonably enough: they just did not consider the needs of the natural environment, which suffered greatly
when its inadequate supply was reduced to critical levels by drought. The members of the Murray-Darling
Basin Commission are now frantically trying to extricate themselves from the disastrous results of their
misallocation of the total water resource. Given the difficulties of sensibly apportioning the water supply within
a single nation, imagine the complexities of doing so for international river basins such as that of the Jordan
River, which borders on Lebanon, Syria, Israel, the Palestinian areas, and Jordan, all of which have claims to
the shared, but limited, supply in an extremely parched region. The struggle for freshwater has contributed to
civil and military disputes in the area. Only continuing negotiations and compromises have kept this tense
situation under control.
Questions 1-5: Do the following statements agree with the information in Passage 1? Write:
TRUE – FALSE - NOT GIVEN
1. The prospect for the need for freshwater worldwide is obscure.
2. To some extent, the challenge for freshwater is alleviated by common recognition.
3. Researchers arrive at the specific conclusion about the water crisis based on persuasive consideration of
several factors.
4. The fact is that people do not actually cherish the usage of water scarcity.
5. Controversy can’t be avoided for adjacent nations over the water resource.
Questions 6-10: The readings Passage has eleven paragraphs A-I. Which paragraph contains the
following information? NB You may use any letter more than once.
6. The uneven distribution of water around the world.
7. other factors regarding nature bothering people who make the policies.
8. Joint efforts needed to carry out the detailed solutions combined with various aspects.
9. No always-in-time match available between the requirements and the actual rainfall.
10. The lower limit of the amount of fresh water for a person to survive.
Questions 11-13: Complete the following summary, using NO MORE THAN THREE words from the
Passage for each answer.
Many severe problems like starvation and military actions etc result from the storage of water which
sometimes for some areas seems 11 ……………………………… because of unavailability but other regions
suffer another kind of scarcity for insufficient support. 12………………………….…….of the rainfall can’t be
achieved because of evaporation. Some other parts form the 13 ……………………………
PASSAGE 2
How war debris could cause cancer
A - Could the mystery over how depleted uranium might cause genetic damage be closer to being solved? It
may be, if a controversial claim by two researchers is right. They say that minute quantities of the material
lodged in the body may kick out energetic electrons that mimic the effect of beta radiation. This, they argue,
could explain how residues of depleted uranium scattered across former war zones could be increasing the
risk of cancers and other problems among soldiers and local people.
B - Depleted uranium is highly valued by the military, who use it in the tips of armourpiercing weapons. The
material’s high density and self-sharpening properties help it to penetrate the armour of enemy tanks and
bunkers. Its use in conflicts has risen sharply in recent years. The UN Environment Program (UNEP) estimates
that shells containing 1700 tonnes of the material were fired during the 2003 Iraq war. Some researchers and
campaigners are convinced that depleted uranium left in the people exposed to it. Governments and the
military disagree, and point out that there is no conclusive epidemiological evidence for this. And while they
acknowledge that the material is weakly radioactive, they say this effect is too small to explain the genetic
damage at the levels seen in war veterans and civilians.
C - Organizations such as the UK’s Royal Society, the US Department of Veterans Affairs and UNEP have
called for more comprehensive epidemiological studies to clarify the link between depleted uranium and any ill
effects. Meanwhile, various test-tube and animal studies have suggested that depleted uranium may increase
the risk of cancer, according to a review of the scientific literature published in May 2008 by the US National
Research Council. The authors of the NRC report argue that more long-term and quantitative research is
needed on the effects of uranium’s chemical toxicity. They say the science seems to support the theory that
genetic damage might be occurring because uranium’s chemical toxicity and weak radioactivity could
somehow reinforce each other, though no one knows what the mechanism for this might be.
D - Now two researchers, Chris Busby and Ewald Schnug, have a new theory that they say explains how
depleted uranium could cause genetic damage. Their theory invokes a well-known process called the
photoelectric effect. This is the main mechanism by which gamma photons with energies of about 100
kiloelectronvolts (keV) or less are blocked by matter: the photon transfers its energy to an electron in the
atom’s electron cloud, which is ejected into the surroundings.
An atom’s ability to stop photons by this mechanism depends on the fourth power of its atomic number - the
number of protons in its nucleus - so heavy elements are far better at intercepting gamma radiation and X-rays
than light elements. This means that uranium could be especially effective at capturing photons and kicking out
damaging photoelectrons: with an atomic number of 92, uranium blocks low-energy gamma photons over 450
times as effectively as the lighter element calcium, for instance.
E - Busby and Schnug say that previous risk models have ignored this well-established physical effect. They
claim that depleted uranium could be kicking out photoelectrons in the body’s most vulnerable spots. Various
studies have shown that dissolved uranium - ingested in food or water, for example - is liable to attach to DNA
strands within cells, because uranium binds strongly to DNA phosphate. “Photoelectrons from uranium are
therefore likely to be emitted precisely where they will cause most damage to genetic material,” says Busby.
Busby and Schnug base their claim on calculations of the photoelectrons that would be produced by the
interation between normal background levels of gamma radiation and uranium in the body. “Our detailed
calculations indicate that the phantom photoelectrons are the predominant effect by far for uranium genome
toxicity, and that uranium could be 1500 times as powerful as an emitter of photoelectrons than as an alpha
emitter.” Their computer modelling results are described in a peer-reviewed paper to be published in this
month by the IPNSS in a book called Loads and Fate of Fertiliser Derived Uranium.
G - Hans-Georg Menzel, who chairs the International Commission on Radiological Protection’s committee on
radiation doses, acknowledges that the theory should be considered, but he doubts that it will prove significant.
He suspects that under normal background radiation the effect is too weak to inflict many of the “double hits” of
energy that are known to be most damaging to cells. “It is very unlikely that individual cells would be subject to
two or more closely spaced photoelectron impacts under normal background gamma irradiation,” he says.
Despite his doubts, Menzel raised the issue last week with his committee in St Petersburg, Russia, and says
that several colleagues “intended to collect relevant data and perform calculations to check whether there was
any possibility of a real effect in living tissues”. Organisations in the UK, including the Ministry of Defence and
the Health Protection Agency, say they have no plans to investigate Busby’s hypothesis.
H - Radiation biophysicist Mark Hill of the University of Oxford would like to see a fuller investigation, though he
suggests this might show that the photoelectric effect is not as powerful as Busby claims. “We really need
more detailed calculations and dose estimates for realistic situations with and without uranium present,” he
says. Hill’s doubts centre on an effect called Compton scattering, which he believes needs to be factored into
any calculations. With Compton scattering, uranium is only 4.5 times as effective as calcium at stopping
gamma photons, so Hill says that taking it into account would reduce the relative importance of uranium as an
emitter of secondary electrons. If he is right, this would dilute the mechanism proposed by Busby and Schnug.
I - The arguments over depleted uranium are likely to continue, whatever the outcome of these experiments.
Whether Busby’s theory holds up or not remains to be seen, but investigating it can only help to clear up some
of the doubts about this mysterious substance.
Questions 14-18: The reading Passage has nine paragraphs A-I. Which paragraph contains the
following information? NB you may use any letter more than once
14. a famous process is given relating to the new theory.
15. a person who acknowledges but suspects the theory.
16. the explanation of damage to DNA.
17. a debatable and short explanation of the way creating the problems of soldiers.
18. Busby’s hypothesis is not in the investigation plans of organizations.
Questions 19-22: Do the following statements agree with the information in Passage 2? Write:
YES – NO - NOT GIVEN
19. All people believe that depleted uranium is harmful to people’s health.
20. Heavier elements can perform better at preventing X-rays and gamma radiation.
21. By particular calculations, it is known that the main effect of uranium genome toxicity is phantom
photoelectrons.
22. Most scientists support Mark Hill’s opinion.

Questions 23-26: Complete the following summary of Passage 2, using NO MORE THAN TWO WORDS
from the Passage for each answer.
23 ……………………………..attaches importance to depleted uranium due to its 24………………………. and
25
…………………………….features, which are helpful in the war. However, it has ill effects in people, and then
causes organizations’ appeal to do more relative studies. According to some scientists, we should do research
about the impact of uranium’s 26…………………………… which may be enhanced with weak radioactivity.
PASSAGE 3
Relish the flavor - how the brain perceives flavor
A. The terms “taste” and “flavor” are used interchangeably. Strictly speaking, however, taste refers to five basic
qualities: salty, sour, sweet, bitter and umami (a characteristic of protein-rich foods such as meat and cheese).
Smell plays an equally prominent role in flavor but is often underappreciated. Try holding your nose and
popping a strawberry- flavored sweet in your mouth. You will taste the sweetness, but not the strawberry until
you let go of your nose and the volatile chemicals from the confectionery enter the nostrils. As if that were not
complex enough, irritants—for example, carbonation or the coolness of mint—are detected not by taste or
smell, but by the trigeminal sense, a part of the touch system adapted for the mouth. The brain receives news
about what is in the mouth from receptors—proteins specialized in picking up particular molecules—located
throughout the oral and nasal cavities. Receptors for smell were identified in the early 1990s, and for sweet,
bitter and umami only in the past two years (sour and salty tastes were somewhat better understood). That,
says Gary Beauchamp, director of the Monell Chemical Senses Institute in Philadelphia, whose group
contributed to some of the findings, is more than has been learnt about taste in the past 2,000 years. A
receptor for capsaicin, the molecule that gives chili peppers their bite, was identified only in 1997.
B. The discovery of taste receptors opens the way to mimicking, enhancing or blocking them for various
desired effects—such as increasing the salty taste of low-sodium foods, or preventing the bitterness that
characterizes many medicinal drugs, or boosting the flavors of diets for the elderly to ensure they eat properly.
But receptors are only part of the story. Nobody knows how the brain distinguishes a mouthful of milk from a
bite of bread, or chicken tikka masala in an Indian restaurant from one bought at a supermarket. Although
some scientists argue that the brain’s response to stimuli is a simple map of the receptors in the tongue and
nose, a more compelling theory suggests that the overall patterning of signals together creates a sense of
particular flavors, whose attractiveness is judged in the light of previous experience.
There are no useful algorithms to measure brain inputs and outputs against subjective reports of flavor
sensations. That is good news for neurophysiologists looking for work. But for flavor and fragrance companies
—with global sales of flavors accounting for more than a third of the $35 billion-a-year food ingredients market
—acceptable tastes bear directly on the bottom line. There is no question that flavor is the most important
criterion for consumer acceptance of foods. And being able to predict what customers will like is the industry's
greatest single ambition.
C. Throughout history, flavors have been coveted for their ability to increase the palatability of food and to
enliven cuisine. In 408, Alaric the Visigoth's price for raising siege of Rome allegedly included more than 1,000
kilograms of pepper. Industrial production of perfumes began in France in the 18th century to take the smell
out of leather gloves. The flavor industry was a logical consequence of such developments. Extracts and
essential oils such as citrus were being produced in America by the late 1700s. In 1874, Haarmann and
Reimer in Germany became the first company to make synthetic vanillin (from the sap of conifers) on an
industrial scale. At first, isolating and identifying gustatory ingredients proved extremely hard. Not only were
analytical methods rudimentary, but the substances responsible for taste are present in minuscule amounts
even in concentrated foods such as crushed raspberries. After 1950, new analytical techniques made it
possible to detect trace ingredients, and companies accumulated chemical libraries that today contain
thousands of compounds.
D. Depending on what a customer wants, flavors can be used off the shelf, modified or created a new,
following a principle called GRAS (generally recognized as safe). It is a constant challenge to be unique, says
Bob Eilerman, leader of flavor research and development for Givaudan, a Swiss company whose scientists
float over tropical rainforests in hot-air balloons to find new tastes and ingredients, capture their aromas on
site, and then analyze and re-create them in the laboratory. The most potent flavored chemicals are created
by cooking, says Anthony Blake, vice-president of food science and technology at Firmenich in Geneva.
Firmenich, Givaudan and International Flavors and Fragrances, the industry leader in America, comprise the
big three of flavour and fragrance companies world-wide. Small wonder that Firmenich employs techno-chefs,
or that Givaudan dispatches analysts to ethnic restaurants hither and yon.
E. Like colorists grinding and mixing pigments, professional flavourists assemble the 50-100 components that
are typical for a flavor into the finished product. Acceptability is measured using panels of expert and
consumer (ie, naive) taste-testers in a process called sensory analysis. Trained testers might be asked to rate
the taste of vanilla ice-cream according to standards for sweetness and vanilla flavor, whereas consumer
testers simply register whether they like it. The process is an iterative one, with several rounds of refinement
between testers and flavourists, until the product is deemed to have an acceptable taste.
Unfortunately, says Alex Haussler, director of flavor excellence at Givaudan, while humans provide the most
sensitive testing instrument, they are not the most reliable. People are born with different sets of taste
receptors and different ways of interpreting them. Think of the last time you watched somebody pour spoonfuls
of sugar into a cup of coffee. Texture is a particular conundrum. It contributes substantially to the pleasure of
eating, yet very little is known about it. Why is rubbery squid enjoyable and rubbery toast not? What does
“succulent” mean? Since the 1960s, the food industry has devised a battery of instrument tests for desired
textural properties, including poking peas with pins and bending biscuits. But theory has been lacking, and
giving a carrot a whack bears little resemblance to what happens inside the mouth, where it is traversed by a
multitude of physicochemical processes. Julian Vincent of the University of Bath, in Britain, is one of a small
band of academic researchers who are trying to relate the results of mechanical tests to perceptions such as
crispness.
F. The dynamics of flavor release—ie, the appearance and disappearance of flavor—have also resisted
measurement. Researchers at the University of Nottingham, also in Britain, have developed and
commercialized an instrument called MS-Nose that sucks in breath from a person's nose while they are
chewing gum, for instance, and analyses the aroma molecules it finds there. Firmenich has adopted the
technology in its search for better ways of delivering flavor. The approach has stimulated a good deal of
interest, even though the results tend to be unique to the person tested.
Physiological studies of flavor are conducted using animals (mostly rats and hamsters) or bacteria, which have
robust taste receptors. In humans, techniques such as functional magnetic-resonance imaging and positron-
emission tomography—currently being applied to problems as diverse as working memory and lovesickness—
can reveal patterns of electrical activity swishing around the brain in real time, says Dr Blake. The idea is to get
a person to eat something and see what parts of their brain light up. But the technologies are not yet sensitive
enough, nor are the ways of analyzing the data meaningful enough, for the methods to be useful in studies of
flavor. An alternative approach, says Monell's Dr. Beauchamp, would be to focus on specific genes in animals
and alter them to track the pathways that the brain uses in integrating signals from the receptors.
G. At present, finding the right enhancer or blocker for a given receptor means looking at thousands of
compounds, a task better suited to automated testing than the caprices of the human tongue. Senomyx, a
young biotech company in La Jolla, California, intends to use such a technology, called “high-throughput
screening”, to test legions of compounds against taste and smell receptors. Whether the technique will prove
more successful in food science than in pharmaceutical research and development, where it is widely used but
has not yet produced a blockbuster drug, remains to be seen. Another biotech firm, Linguagen of Paramus,
New Jersey, is also bringing modern science to bear in the search for flavor modifiers, particularly bitterness
blockers.
H. The mouth is the portal of entry to the gut, and taste is the final arbiter. Innate aversions to sour and bitter
substances—caffeine, nicotine, strychnine, for example—and a liking for sweet and salty ones reflect the wise
choices that humanity's ancestors made in a hostile environment. Beyond these protective and nutritional
reflexes, however, taste preferences are largely a matter of culture and learning. The taste system is
reasonably compliant, says Tom Scott, a neurophysiologist and dean of sciences at San Diego State
University in California. Cultures are kept distinct by cuisines, and cuisines are distinguished by taste.
But cuisines, like continents, have a habit of colliding. Ten years ago, few Americans cared for raw fish. Now
they eat sushi almost as avidly as the Japanese. Moreover, “acquired tastes” often involve complex
contradictions that play tricks within the brain. How else do you explain the liking for strong-smelling cheese or
the East Asian fruit called durian that is so redolent of vomit that it is banned on public transport in some
countries? Other effects resist reconciliation, like the unbearable sweetness that artichokes lend to wine.
Flavor appears to belong to a family of subtle perceptions—such as recognizing a voice or telling faces apart.
But how does the central nervous system process all the information needed to make these fine-grained
distinctions? The answer should help to develop cheaper and safer flavor compounds, as well as to perform
tricks of alchemy such as turning tofu into steak. More fundamentally, identifying algorithms in the brain that
transform taste into flavor, and comparing them with how people process complex sounds or tactile sensations,
might reveal something about how perception really works.
Questions 28 – 35: The Passage has six paragraphs A-H Which paragraph contains the following
information? NB: you may use the letter more than once
28. the process of the new food flavor is agreed on
29. the reason for some natural preferences
30. the reason why flavor has not been researched in depth in the past.
31. the explanation of lack of consistency in sensory analyzing data.
32. the wider benefits to the knowledge of researching flavors.
Questions 32-36: Do the following statements agree with the information in Passage 3? Write:
TRUE – FALSE - NOT GIVEN
32. Both taste and flavor can be experienced only in mouth.
33. Some elements in flavor involve neither taste nor smell.
34. Ice-cream manufactures are at the forefront of the research on flavor
35. It is possible to accurately match the brain activity to the experience of flavor.
36. Research is being done to the controlling of the experience of taste.
Questions 37-40: Look at the following statements and the list of researchers below. Match the person
with their opinions. NB You may use any letter more than once.
List of researchers:
A. Givaudan 37. Matching brain activity and food input
B. University of Bath 38. Use genetic modification to track flavor signals
C. University of Nottingham 39. Matching textural qualities of food and sensation
D. Firmenich 40. Identify elements in certain smells
E. Chemical senses Institute
F. Linguagen

WRITING PRACTICE
TASK 2: Some says that the most important thing about being rich is that one has the opportunity to
help others. To what extent do you agree or disagree