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"Salty" Rice Plant Boosts HarvestsBritish scientists are breeding a new generation of rice plants that will be able to grow in soil containing salt water. Their work may enable abandoned farms to become productive once more.Tim Flowers and Tony Yeo, from Sussex University"s School of Biological Sciences, have spent several years researching how crops, such as rice, could he made to grow in water that has become salty.The pair has recently begun a three-year programme, funded by the Biotechnology and Biological Sciences Research Council, to establish which genes enable some plants to survive salty conditions. The aim is to breed this capability into crops, starting with rice.It is estimated that each year more than 10 million hectares (公顷) of agricultural land are lost because salt gets into the soil and stunts (妨碍生长) plants. The problem is caused by several factors. In the tropics, mangroves (红树林) that create swamps (沼泽) and traditionally formed barriers to sea water have been cut down. In the Mediterranean, a series of droughts have caused the water table to drop, allowing sea water to seep (渗透) in. In Latin America, irrigation often causes problems when water is evaporated (蒸发) by the heat, leaving salt deposits behind.Excess salt then enters the plants and prevents them functioning normally. Heavy concentrations of minerals in the plants stop them drawing up the water they need to survive.To overcome these problems, Flowers and Yeo decided to breed rice plants that take in very little salt and store what they do absorb in cells that do notaffectthe plants" growth. They have started to breed these characteristics into a new rice crop, but it will take about eight harvests before the resulting seeds are ready to be considered for commercial use.Once the characteristics for surviving salty soil are known, Flowers and Yeo will try to breed the appropriate genes into all manners of drops and plants. Land that has been abandoned to nature will then be able to bloom again, providing much needed food in the poorer countries of the world. Which of the following statements about Flowers and Yeo is true
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Global warming would have a devastating impact on low, lying island.
Houses in 18th Century North AmericaSeventeenth-century houses in colonial North America were simple structures that were primarily functional, carrying over traditional designs that went back to the Middle Ages. During the first half of the eighteenth century, however, houses began to show a new elegance. As wealth increased, more and more colonists built fine houses.Since architecture was not yet a specialized profession in the colonies, the design of buildings was left to carpenters who undertook to interpret architectural manuals imported from England. There are an astonishing number of these handbooks for builders in colonial libraries, and the houses erected during the eighteenth century show their influence. Most domestic architecture of the first three-quarters of the eighteenth century displayed a wide range of taste and freedom of application of the rules laid down in these books.Increasing wealth throughout the colonies resulted in houses of improved design, whether the material was wood, stone or brick. New England still favored wood, though brick houses became common in Boston and other towns, where the danger of fire forced people to use more durable material. A few houses in New England were built of stone, but only in Pennsylvania and its neighboring areas was stone widely used in dwellings. An increased use of bricks is noticeable in Virginia and Maryland, but wood remained the most popular material even in houses built by wealthy landowners. In the Carolinas, even in the crowded town of Charleston, wooden houses were much more common than brick houses.Eighteenth-century houses showed great interior improvements over their predecessors. Windows were made larger and shutters (百叶窗) removed. Large, clear panes (玻璃窗) replaced the gray glass of the seventeenth century. Doorways were larger and more decorative. Fireplaces became decorative features of rooms. Walls were sometimes elaborately decorated. White paint began to take the place of blue, yellow, green and gray colors, which had been popular for walls in the earlier years. After about 1730, advertisements for wallpaper styles in scenic patterns began to appear in colonial newspapers. What does the passage mainly discuss
I had nothing to say regarding this matter.
Cheating deserves our harshest condemnation.
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