15000 bài tập tách từ đề thi thử môn Tiếng Anh có đáp án (Phần 19)

The pain of a migraine headache can virtually disable a person who suffers from it. Millions and millions of people suffer from migraines, although many of them do not even recognize that a migraine is different from a regular headache. A migraine is not at all the same as a normal headache, and it seems to have a very physical cause.

 One symptom of a migraine is a precursor, which is a visual aura before an attack. Yet only about a third of patients actually experience that, and it is therefore not a requirement in the diagnosis. Other symptoms include increased pain when a person moves, nausea, and sensitivity to light and sound. Scientists now believe that migraines are caused, not by abnormal blood vessels as previously believed, but instead by a unique electrical disorder of brain cells. Physicians used to treat migraines with medicine to constrict blood vessels because of the belief that dilated blood vessels were the cause.

 The new research has been enhanced by imaging devices that allow scientists to watch patients' brains during an attack. The results show that sufferers have abnormally excitable neurons, or brain nerve cells. Prior to the attack, the neurons suddenly fire off electrical pulses at the back of the brain, which ripple like waves on a lake after a stone hits the water. They ripple across the top and then the back of the brain, ultimately affecting the brain stem where the pain centers are located. The pain then generates possibly from the brain stem itself or from blood vessels inflamed by the rapidly changing blood flow, or perhaps from both.

 Scientists have experimented by applying a powerful magnet to stimulate the neurons and discovered that some people's brains react differently than others'. When stimulation was applied to the brains of people who had suffered migraines, they saw the initial aura, and some actually suffered migraines. When the same stimulation was applied to the brains of people who had never suffered migraines, they realized no effect and the neurons showed no change.

 Scientists and doctors continue to work on the research in an attempt to find the perfect treatment. It is considered important to treat migraines because it is believed that prolonged untreated attacks could cause physical changes in the brain leading to chronic pain.

 Line Europeans who arrived in the Americas, the first American Indians were immigrants. Because Indians were nomadic hunters and gatherers, they probably arrived in search of new hunting grounds from Asia when they crossed the ice-covered Bering Strait to Alaska. Anthropologists estimate that the entire Indian population north of Mexico was slightly greater than 1,020,000 when the first settlers arrived from Europe. Although Native Americans belonged to one geographic race, their cultures and languages were only marginally similar, and by and large, they had different ways of life. Nomadic migrations required Indians to construct shelters that did not need to be transported, but could be easily erected from the materials found in their new location.

 Eastern Woodland Indian tribes lived in bark-covered wigwams that were shaped like cones or domes. The frame for the hut was made of young trees firmly driven into the ground, and then bent overhead to tie together with bark fibers or strings of animal hides. Sheets and slabs of bark were attached to the frame to construct the roof and walls, leaving an opening to serve as a door and to allow smoke to escape. The Iroquois in north eastern regions built longhouses that were more spacious than wigwams because five to a dozen families lived under one roof. During the winter, they plastered clay to the poles of the frame to protect the inhabitants from wind and rain.

 Pueblo Indians who lived in the southwest portion of the United States in northern Arizona and New Mexico constructed elaborate housing with several stories and many rooms. Each family unit had only one room, and their ancestors dug shelters in the walls of cliffs and canyons. The ground story of a Pueblo dwelling had no doors or windows in order to prevent enemies from entering. The next level was set back the width of one room, and the row of rooms above it was set back once again, giving their houses the appearance of a terrace Pueblos used ladders to climb to the upper levels and pulled them in when all family members returned for the night.

 Indians living in deserts used sandstone and clay as construction materials. Those who lived in the valleys of rivers even made bricks of clay with wood chips to add strength and to prevent the clay from cracking. To make roofs, Pueblos tied logs together to make rafters and laid them across the two outside walls. On top of the rafters, layers of tree branches, sticks, grass, and brush created a solid roof to preclude the water from leaking inside. Pueblo dwellings were dark because windows were often not large enough to allow much light.

The problem of cardiac arrest has become a major problem these days. A lot of patients have acute pain after suffering from a stroke. There are plenty of medicines, surgical methods developed in the field of medicine to treat such cardiac problems. These solutions are time consuming and costly. In the process of rehabilitation, the medicines also have a lot of side effects on the human body and take time to give relief. Therefore, a lot of people go for alternative therapies that help in rehabilitation of patients who suffer from cardiac stroke. The alternative therapies help in relieving pain, stress and make the body healthy and fit through exercise, yoga as well as meditation.

 Those who have the cardiac complaint have to take a good care of their diet. Also, they must look after their regular exercise in order to stay fit and make sure that they do not take undue stress. These are some of the precautions that you need to take while you are in the process of rehabilitation. The cardiac rehabilitation can be carried out at the rehabilitation centers as well as at the residence of the patients. Once the patient learns all the exercise and techniques of meditation and understands what diet he or she should include in their meals as the instructions of the doctor’s and dieticians, then it is possible to accomplish the rehabilitation process at home with little guidance and monitoring. But the best results are seen at the center, where the program is given to a group of patients together.

 The alternative therapies used for cardiac rehabilitation are stress management, physical exercises and diet. Stress management is very much essential in the rehabilitation process because it has a lot of effects on the patient’s body. A lot of relaxation techniques are taught to the patients that helps them in stress management, among them meditation is one of the main focuses.

 The various rehabilitation programs also give you information on how to have a stress free lifestyle. The patients are supported and encouraged to discuss their problems with the counselor or fellow patients. This helps them to vent their feelings and feel comforted. Breathing exercises are also of great help for the patients who are undergoing cardiac rehabilitation.

 In addition to stress management, physical exercises are also given a lot of importance in the rehabilitation program. The patients are asked to perform various forms of physical exercise which are suitable to them depending on their age and the severity of their problems. These activities include activities like walking, jogging, cycling, and some other sports like badminton, tennis etc., to maintain their health and keep their muscles, bones, and body tissues in a good state. Cardio exercise in a gymnasium is also encouraged. This helps in strengthening the muscles and managing weight.

 The diet of these patients also needs to be looked upon very carefully. Such people should stay away from alcohol and tobacco consumption in order to improve their health. Make sure that their meals include plenty of organic foodstuffs as well as fruits and juices. Do not include junk and oily foodstuffs in your diet because they are very difficult to digest. The intake of calories should also be done at required level. It is a significant fact that the patients have to understand and work accordingly.

ACADEMICS AREN’T THE PROBLEM

Studies about how students use their time might shed light on whether they face increased academic and financial pressures compared with earlier eras.

Based on data about how students are spending time, academic or financial pressures don’t seem to be greater now than a generation ago. The data show that full-time students in all types of colleges study much less now than they did a generation ago - a full 10 hours a week less. Students are also receiving significantly higher grades. So it appears that academic pressures are, in fact, considerably lower than they used to be.

The time-use data don’t suggest that students feel greater financial pressures, either. When the time savings and lower opportunity costs are factored in, college appears less expensive for most students than it was in the 1960s. And though there are now full-time students working to pay while in college, they study less even when paid work choices are held constantly.

In other words, full-time students do not appear to be studying less in order to work more. They appear to be studying less and spending the extra time on leisure activities or fun. It seems hard to imagine that students feeling increased financial pressures would respond by taking more leisure.

Based on how students are spending their time, then, it doesn’t look as though academic or financial pressures are greater now than a generation ago. The time- use data don't speak directly to social pressures, and it may well be that these have become more intense lately.

In one recent set of data, students reported spending more than 23 hours per week either socializing with friends or playing on the Computer for fun. Social activities, in person or on Computer, would seem to have become the major focus of campus life. It is hard to tell what kinds of pressures would be associated with this change.

The official residence of the president of the United States is the White House, located at 1600 Pennsylvania Avenue, in Washington, D.C. The Commissioners of the District of Columbia held a meeting in 1792 and decided to hold a contest for the best design for the Presidential House. James Hoban, an architect born in Ireland, was the winner. His bid for the construction of the mansion asked for $200,000, but the final cost of the building came to twice that amount. The work on the project began during the same year, and the grounds of approximately one and a half miles west of the Capitol Hill were chosen by Major Pierre-Charles L’Enfant, who was in charge of city planning. However, the construction continued for several more years, and George Washington had stepped down as president before the building was habitable. When John Adams, the second president of the United States and his wife Abigail moved in 1800, only six rooms had been completed.

 The grey sandstone walls of the house were painted white during construction, and the color of the paint gave the building its name. The building was burned on August 24, 1814, and James Hoban reconstructed the house for President James Monroe and his family, who moved there in 1817. The north portico was added to the building in 1829, water pipes were installed in 1833, gas lighting in 1848, and electricity in 1891. In 1948, inspectors announced that the building was so dilapidated that it was beyond repair and suggested that it was cheaper to construct a new one than repair the existing dwelling. However, the national sentiment was to keep the original form intact, and Congress appropriated $5million dollars for repairs. In 1961, Jacqueline Kennedy launched a pro.4 gram to redecorate the rooms and appointed a Fine Arts Committee to make choices of furnishing and colors.

 The house of the president accords its residents a great deal of space. The living quarters contain 107 rooms, 40 corridors, and 19 baths. The White House contains a doctor’s suite, a dentist’s office, a large solarium, a broadcasting room, and a two-floor basement for storage and service rooms. The office in which the president works is not located in the White House, but in a separate building called the West Wing. The White House stands on 16 acres of park like land and overlooks a broad lawn, flower gardens, and wood groves.

In the course of history, human inventions have dramatically increased the average amount of energy available for use per person. Primitive people in cold regions burned wood and animal dung to heat their caves, cook food, and drive off animals by fire. The first step toward the developing of more efficient fuels was taken when people discovered that they could use vegetable oils and animal fats in lieu of gathered or cut wood. Charcoal gave off a more intensive heat than wood and was more easily obtainable than organic fats. The Greeks first began to use coal for metal smelting in the 4th century, but it did not come into extensive use until the Industrial Revolution.

 In the 1700s, at the beginning of the Industrial Revolution, most energy used in the United States and other nations undergoing industrialization was obtained from perpetual and renewable sources, such as wood, water streams, domesticated animal labor, and wind. These were predominantly locally available supplies. By mid-1800s, 91 percent of all commercial energy consumed in the United States and European countries was obtained from wood. However, at the beginning of the 20th century, coal became a major energy source and replaced wood in industrializing countries. Although in most regions and climate zones wood was more readily accessible than coal, the latter represents a more concentrated source of energy. In 1910, natural gas and oil firmly replaced coal as the main source of fuel because they are lighter and, therefore, cheaper to transport. They burned more cleanly than coal and polluted less. Unlike coal, oil could be refined to manufacture liquid fuels for vehicles, a very important consideration in the early 1900s, when the automobile arrived on the scene.

 By 1984, nonrenewable fossil fuels, such as oil, coal, and natural gas, provided over 82 percent of the commercial and industrial energy used in the world. Small amounts of energy were derived from nuclear fission, and the remaining 16 percent came from burning direct perpetual and renewable fuels, such as biomass. Between 1700 and 1986, a large number of countries shifted from the use of energy from local sources to a centralized generation of hydropower and solar energy converted to electricity. The energy derived from nonrenewable fossil fuels has been increasingly produced in one location and transported to another, as is the case with most automobile fuels. In countries with private, rather than public transportation, the age of nonrenewable fuels has created a dependency on a finite resource that will have to be replaced.

Puerto Rico, a Caribbean island rich in history and remarkable natural beauty, has a cuisine all its own. Immigration to the island has helped to shape its cuisine, with people from all over the world making various contributions to it. However, before the arrival of these immigrants, the island of Puerto Rico was already known as Borikén and was inhabited by the Taíno people. Taíno cuisine included such foods as rodents with sweet chili peppers, fresh shellfish, yams, and fish fried in corn oil.

(1) Many aspects of Taíno cuisine continue today in Puerto Rican cooking, but it has been heavily influenced by the Spanish, who invaded Puerto Rico in 1508, and Africans, who were initially brought to Puerto Rico to work as slaves. (2)Taíno cooking styles were mixed with ideas brought by the Spanish and Africans to create new dishes. (3) Africans also added to the island’s food culture by introducing powerful, contrasting tastes in dishes like piñon–plantains layered in ground beef. In fact, much of the food Puerto Rico is now famous for—plantains, coffee, sugarcane, coconuts, and oranges—was actually imported by foreigners to the island. (4)

A common assumption many people make about Puerto Rican food is that it is very spicy. It’s true that chili peppers are popular; ajícaballero in particular is a very hot chili pepper that Puerto Ricans enjoy. However, milder tastes are popular too, such as sofrito. The 25 base of many Puerto Rican dishes, sofrito is a sauce made from chopped onions, garlic, green bell peppers, sweet chili peppers, oregano, cilantro, and a handful of other spices. It is fried in oil and then added to other dishes.

(Adapted from: Reaing Explorer 2, by Paul MacIntyre, 2009, Heinle, Cengage Learning)

Where one stage of child development has been left out, or not sufficiently experienced, the child may have to go back and capture the experience of it. A good home makes this possible - for example, by providing the opportunity for the child to play with a clockwork car or toy railway train up to any age if he still needs to do so. This principle, in fact, underlies all psychological treatment of children in difficulties with their development, and is the basic of work in child clinics.

The beginnings of discipline are in the nursery. Even the youngest baby is taught by gradual stages to wait for food, to sleep and wake at regular intervals and so on. If the child feels the world around him is a warm and friendly one, he slowly accepts its rhythm and accustoms himself to conforming to its demands. Learning to wait for things, particularly for food, is a very important element in upbringing, and is achieved successfully only if too great demands are not made before the child can understand them. Every parent watches eagerly the child's acquisition of each new skill: the first spoken words, the first independent steps, or the beginning of reading and writing. It is often tempting to hurry the child beyond his natural learning rate, but this can set up dangerous feelings of failure and states of anxiety in the child. This might happen at any stage. A baby might be forced to use a toilet too early, a young child might be encouraged to learn to read before he knows the meaning of the words he reads. On the other hand, though, if a child is left alone too much, or without any learning opportunities, he loses his natural zest for life and his desire to find out new things for himself.

Learning together is a fruitful source of relationship between children and parents. By playing together, parents learn more about their children and children learn more from their parents. Toys and games which both parents and children can share are an important means of achieving this co-operation. Building-block toys, jigsaw puzzles and crosswords are good examples.

Parents vary greatly in their degree of strictness or indulgence towards their children. Some may be especially strict in money matters; others are severe over times of coming home at night, punctuality for meals or personal cleanliness. In general, the controls imposed represent the needs of the parents and the values of the community as much as the child's own happiness and well-being.

With regard to the development of moral standards in the growing child, consistency is very important in parental teaching. To forbid a thing one day and excuse it the next is no foundation for morality. Also, parents should realize that "Example is better than precept". If they are hypocritical and do not practice what they preach, their children may grow confused and emotionally insecure when they grow old enough to think for themselves, and realize they have been, to some extent, deceived. A sudden awareness of a marked difference between their parents' ethics and their morals can be a dangerous disillusion.

Sir Anthony Van Dyck, one of the world’s greatest masters of portraiture, was born in Antwerp and was the seventh of twelve children. His affluent father apprenticed him to a painter when he was just a little over ten. Having become a member of the Antwerp Guild of painters before he was nineteen, he worked in the studio of Peter Paul Rubens for several years. In Italy, Van Dyck studied the great Venetian masters and painted flattering portraits of gorgeous ladies and haughty nobles in gilded velvet robes with lace and pearls. While he was sought after by the aristocracy for his acclaimed loose brushwork, his engravings and etchings also evinced his outstanding talent. Upon his return to Antwerp in 1628, he was influenced by Rubens’s interpretation of the artistic form and produced numerous religious paintings while holding an appointment as the court painter. During his tenure, he proved that his use of color, his sensitive elegance, and his remarkable insight were unexcelled.

His fame preceded him to England, where he was invited by King Charles I. After years of faithful service, he was knighted in recognition of his achievements in painting countless portraits of the king, the queen, the royal children, and the titled nobility of England.

However, Van Dyck’s greatest piece is one of his religious works, a true masterpiece displayed in the Antwerp gallery. This group scene exhibits his artful polish in painting the folds of fabric, the delicacy of human skin, landscape, and other externals, and puts him above other accomplished contemporary masters. Although Charles paid Van Dyck a salary and granted him a pension, the painter’s extravagant life-style and penchant for luxuries led him into debt, and he died without means.

ACID DUST

“ Calcite- containing dust particles blow into the air and combine with nitric acid in polluted air from factories to form an entirely new particle – calcium nitrate , ” said Alexander Laskin, a senior research scientist at the Department of Energy’s Pacific Northwest National Laboratory in Richland, Washington .These nitrates have optical and chemical properties that are completely different from those of the originally dry dust particles . Due to this, climate models need to be updated to reflect this chemistry. Calcite dust is common in arid areas such as Israel, where scientists collected particles for analysis.

 Working from a mountaintop, the team collected dust that had blown in from the northern shores of Egypt, Sinai,and southern Israel. The particles had combined with air containing pollutants that came from Cairo.They analyzed nearly 2,00 individual particles and observed the physical and chemical changes at the W.R Wiley Environmental Sciences Laboratory.

 A key change in the properties of the newly formed nitrate particles is that they begin to absorb water and retain the moisture .These wet particles can scatter and absorb sunlight-presenting climate modelers, who need to know where the energy is going , a new wild card to deal with . Companion studies of dust samples from the Sahara and the Saudi coast and loess from China show that the higher the calcium in the mineral , the more reactive they are in with nitric acid .And once the particle is changed , it stays that way.

 “When dust storms kick up these particles and they enter polluted areas , the particles change ,” Laskin said . “To what extent this is happening globally, as more of the world becomes industrialized , we don’t know . But now we have the laboratory and field evidence that shows it is definitely happening . The story is much more complicated than anybody thought .”