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3. With Genetic Gift, 2 Monkeys Are Viewing a More Colorful World Dalton and Sam are male squirrel monkeys, about a foot tall. (46) Dalton and Sam lead a more protected life in the laboratory of Jay and Maureen Neitz at the University of Washington, Seattle. Recently, the Neitzes endowed them with a new genetic gift : the ability to see the world with full color vision. Male squirrel monkeys have only two of the color pigments (色素) known as opsins (视蛋白), unlike people who have three. The Neitzes, with Katherine Mancuso and other colleagues, used the technique of gene therapy to introduce the gene for the missing red pigment into the cone cells of the monkeys’ retinas (视网膜). (47) It was somewhat surprising that the monkeys’ brains could take advantage of a third opsin. The retina, however, seems to work by recording the difference between the signals from neighboring cones, the cells that detect color. (48) New World male monkeys like Dalton and Sam are chromatically challenged because their ancestors split off from Old World primates before full color vision evolved. At the time of the split, primates had only two visual pigments, one that is particularly sensitive to blue light and another that responds best to either green or red, depending on which variant of the gene is inherited. (49) The gene for the red or green opsin was duplicated, allowing individuals to see red and green instead of just one or the other. New World monkeys never developed the duplicated gene, but many females have full color vision nevertheless. The reason is that the red/green opsin gene lies on the X chromosome, so females who inherit a different version from each parent have both red and green opsins along with the blue opsin on another chromosome (染色体). (50) A. But males, with only one X chromosome, inherit just one variant of the red/green opsin - the green in the case of Dalton and Sam.B. Several months after the therapy, Dalton and Sam were able to see a world in which red hues (颜色) were visible and oranges no longer looked like lemons, the researchers say in the current issue of Nature.C. Their ancestors lived by eating fruit and insects in the forest canopy (树荫) of Central and South America.D. After the split, which began with the opening of the Atlantic between Africa and South America some 150 million years ago, the Old World primates benefited from a genetic accident.E. So the extra opsin gene given to Dalton and Sam would have changed the signal from affected cones and hence the message forwarded from the retina to the visual cortex in the brain.F. The monkey experiment would help researchers understand the circuitry used by the primate brain to analyze color.
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In the United States, older people rarely live with their adult children. But in many other cultures children are expected to care (51) their aged parents. In some parts of Italy, the percentage of adult children who (52) with their parents reach 65 to 70 percent. In Thailand, too, children are expected to care for their elderly parents ;few Thai elderly live (53) . What explains these differences in living arrangements (54) cultures Modernization theory (55) the extended family household to low levels of economic development. In traditional societies, the elderly live with their children in large extended family units for economic reasons. But with modernization, children move to urban areas, leaving old people behind in (56) rural areas. Yet modernization theory cannot explain why extended family households were never common in the United States or England, or why families in Italy, which is fully modemized, (57) a strong tradition of intergenerational living. Clearly, economic development alone cannot explain (58) living arrangements. Another theory associated intergenerational living arrangements with inheritance patterns. In some cultures, the stem family pattem of inheritance predominates. (59) this system, parents live with a married child, usually the oldest son, who then (60) their property when they die. The stem family system was once common in Japan, but changes in inheritance laws, as well as broader social changes brought (61) by industrialization and urbanization, have (62) the tradition. In 1960about 80 percent of Japanese over 65 lived with their children; by 1990 only 60 percent did - a figure that is still high (63) U.S. standards, but which has been (64) steadily. In Korea, too, traditional living arrangements are (65) : the percentage of aged Koreans who live with a son declined from 77 percent in 1984 to 50 percent just 10 years later. Although most elderly Koreans still expect to live with a son, their adult children do not expect to live with their children when they grow old.
In the United States, older people rarely live with their adult children. But in many other cultures children are expected to care (51) their aged parents. In some parts of Italy, the percentage of adult children who (52) with their parents reach 65 to 70 percent. In Thailand, too, children are expected to care for their elderly parents ;few Thai elderly live (53) . What explains these differences in living arrangements (54) cultures Modernization theory (55) the extended family household to low levels of economic development. In traditional societies, the elderly live with their children in large extended family units for economic reasons. But with modernization, children move to urban areas, leaving old people behind in (56) rural areas. Yet modernization theory cannot explain why extended family households were never common in the United States or England, or why families in Italy, which is fully modemized, (57) a strong tradition of intergenerational living. Clearly, economic development alone cannot explain (58) living arrangements. Another theory associated intergenerational living arrangements with inheritance patterns. In some cultures, the stem family pattem of inheritance predominates. (59) this system, parents live with a married child, usually the oldest son, who then (60) their property when they die. The stem family system was once common in Japan, but changes in inheritance laws, as well as broader social changes brought (61) by industrialization and urbanization, have (62) the tradition. In 1960about 80 percent of Japanese over 65 lived with their children; by 1990 only 60 percent did - a figure that is still high (63) U.S. standards, but which has been (64) steadily. In Korea, too, traditional living arrangements are (65) : the percentage of aged Koreans who live with a son declined from 77 percent in 1984 to 50 percent just 10 years later. Although most elderly Koreans still expect to live with a son, their adult children do not expect to live with their children when they grow old.
Marriage Linked With Better Sleep Marriage may improve your sleep, and better sleep may improve your marriage, two new studies suggest. Women who are married or who have stable partners appear to sleep better than women who have never married or lost a panner, according to research from an eight - year study presented at the Associated Professional Sleep Societies annual meeting. They also found that marital (婚姻的)happiness lowers the risk of sleep problems, while marital conflict heightens the risk. Although married women overall slept more soundly than unmarried women, the researchers, from the University of Pittsburgh School of Medicine, did identify a "newlywed" effect. Women who were single at the start of the study but gained a partner had more restless sleep than women who were akeady married. The researchers speculated that newly married women were less adjusted to sleeping with their partner than those who had been married longer. The study included 360 middle - aged African--American, Caucasian and Chinese. American women who had taken part in the Study of Women’ s Health Across the Nation. Researchers used in--home sleep studies, activity monitors to track sleep--wake patterns and relationship histories to look at the effect stable marriages, unstable marriages and marital transitions, such as a divorce, had on sleep. Another small study of 29 couples found that on a daily basis, the quality of a couple’ s relationship and the quality of their sleep are closely linked. In that study, from the University of Arizona, 29 heterosexual (异性的) couples who shared a bed and did not have children completed sleep and relationship diaries for a week. The results showed that when men get better sleep, they are more likely to feel positive about their relationship the next day. And for women, problems in the relationship were Strongly associated with poor sleep for both themselves and their partner. "When we look at the data on a day - by - day basis, there seems to be a vicious cycle in which sleep affects next day relationship functioning, and relationship functioning affects the subsequent night’s sleep," said principal investigator Brant Hasler, a clinical psychology doctoral candidate at the University of Arizona, in a press release. "In this cycle, conflict with one’ s partner during the day leads to worse sleep that night, which leads to more conflict the following day. " The data from both studies suggest that sleep and relationship happiness are closely linked. The lesson for couples, especially those who are struggling with problems, is that paying attention to sleep habits may help solve other issues in the relationship. Which of the following is true of the 29 couples in a small study from the University of Arizona
The Anti- Alcohol Campaign Tries in Russia Last week Russian President Dmitry Medvedev kicked off a new anti - alcohol campaign aimed at cutting the nation’s per capita consumption of alcohol by nearly a quarter by 2012. Russians currently drink about 18 liters (19 quarts) a year, more than double the 8 liters (8.4 quarts) deemed safe by the World Health Organization (WHO). With each additional liter, adds the WHO, men can subtract 11 months from their average life expectancy. The latest move consists of three parts: a media campaign, restrictions on beer consumption, and strict penalties for selling to minors. Russian officials plan to set up more than 500 health centers by the end of the year, complete with Soviet - era tactics like drawings of cimlosis (肝硬化) - stricken livers on their walls. Even with such aggressive measures, it’ s hardly the most ambitious campaign Russians has ever launched against drinking. Former leader Mikhail Gorbachev got alcohol sales to decline by 60 percent. Three years ago, a group of young Russians organized a sort of Vigilante (治安维持会成员)vice squad to single out and shame merchants who sold alcohol to minors. Supported by the Moscow city administration, the Solar Circle movement, as they called themselves, held rallies, and slapped leaflets on the shop doors of guilty establishments. They piqued (激起，激发) media interest at first, but the momentum soon fizzled (渐停，夭折). Some critics say that, while admirable: it hardly addresses the biggest culprit of all: vodka. "The main problem is the availability of hard liquor," says Aleksandr Nemtsov, a top Russian expert on alcohol policy. Some 70 percent of alcohol consumption in Russia is of the hard stuff, primarily vodka. One attempt, tried in the mid - 1990s, substituted beer as a less intoxicating non - liquor alternative. Instead, "beer has become a gateway opening the way to alcoholism for teenagers," says Oleg Zykov, a member of the Public Chamber. The earlier people start down that route, the more likely they are to end up grappling with (尽力解决) alcoholism problems later. Still, for now, Russians seem to support the government’ s new approach. As the National Center for the Study of Public Opinion reported last week, 65 percent of the population say they are in favor of the new measures - especially those that restrict alcohol sales to those under 21. (Right now, the drinking age is 18. ) Which one of the following measures is not mentioned in the third paragraph
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