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Dietary studies have suggested that people who consume large amounts of vitamin A in foods, multi vitamins, or both are more likely to suffer hip fractures than are people who ingest modest amounts. New evidence bolsters these findings. Researchers have now correlated men"s blood concentrations of vitamin A with a later incidence of broken bones: a comparison that avoids the vagaries that plague diet-recall studies. Taken together, the new work and the diet studies raise knotty questions about the maximum amount of vitamin A that a person can safely ingest each day, says study coauthor Karl Michasson, an orthopedic surgeon at University Hospital in Uppsala, Sweden. He and his colleagues report the new findings in Jan. 23 New England Journal of Medicine. In the United States, the average daily intake of vitamin A through food, specially fish, eggs, and meat, is roughly 2,600 IU (international units) for men, and many multi-vitamins contain 5,000 IU. The US Institute of Medicine recommends that people get 2,300 to 3,000 IU of vitamin A each day and sets the safe upper limit around 10,000 IU. "I believe tiffs upper level should be lowered," Michasson says. When he and his colleagues gave the men dietary questionnaires, they learned that men ingesting as little as 5,000 IU of vitamin A per day were more prone to fractures than were men getting less. Manufacturers should lower the amount of vitamin A in multi-vitamin tablets and fortified foods, such as cereals, says Michasson. The new study began in the early 1970s when researchers stored blood samples from 2,047 men about 50 years old. Since then, 266 of the men have had at least one bone fracture. After dividing the men into five equal groups according to their blood vitamin A concentrations, the researchers found that men in the top group were nearly twice as likely as those in the middle group to have broken a bone. The correlation was particularly strong with fractures of the hip. "I think it"s pretty conclusive now that there"s a bad effect of vitamin A supplementation," says Margo A. Denke, an endocrinologist at the University of Texas Southwestern Medical Center in Dallas. Elderly people may be at special risk because they"re slow to clear the vitamin from their bodies. Studies of animals have established that excess vitamin A stimulates the formation of cells that dissolve bone. However, since some vitamin A is necessary to maintain good eyesight and general health, Denke and Michasson agree that fully fortified foods and supplements should remain available in countries where poor nutrition puts people at risk of a vitamin A deficiency. The passage is mainly about
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Eight months after Sep. 11, it is becoming increasingly apparent that various arms of the US government had pieces of information that, if put together, might have provided sketchy advance warning of the terrorist strikes to come. The White House now acknowledges, that the CIA told President Bush in August that suspected members of A1 Qaeda had discussed the hijacking of airplanes. At the same time, FBI agents were increasingly suspicious of some Middle Eastern men training at US flight schools. Yet the US government didn"t pay attention to this information. "There are always these little indicators that come in—of one sort or another—that don"t get enough decibels to receive attention," say former CIA Director Stansfield Turner. "The possibility of a traditional hijacking—in the pre-9.11 sense—has long been a concern of the government," White House spokesman Ari Fleischer said. But "this was a new type of attack that was not foreseen." In deed, he said the warnings did not suggest commercial airliners would be used as missiles and that the general assumption was that any attack would occur abroad, not in the US. Still, the White House says it did quietly alert several government agencies to the threat. Meanwhile, FBI agents were getting hints of the terrible plot. A classified memo drafted by the bureau reportedly warned in blunt language that Osama bin Laden might be linked to Middle Eastern men taking lessons at US flight schools. Mr. Turner sees this as a painful and avoidable mistake. The basic reason for the lack of coordination and communication is "a very large intelligence bureaucracy that is very compartmentalized," says Charles Penia, a senior defense analyst at the Cato Institute. Today, the disclosures raise a crucial question: Have recent reforms boosted Washington"s ability to pull together information from its many agencies—and thus disrupt future attacks Indeed, since Sep. 11, the government has struggled to improve coordination. One change: FBI data is now merged with CIA intelligence in the president"s daily briefing. Another: A new command center near Washington was set up by White House Homeland Security. It"s one place the CIA, the FBI, the Defense Intelligence Agency, and others are able to coordinate and share information. It"s not clear yet whether they actually will. The text is most probably selected from
The growth of cell phone users in the U.S. has tapered off from the breakneck pace of 50% annually in the late 1990s to what analysts project will be a 15% to 20% rise in 2002, and no more than that in 2003. To some extent, numerous surveys have found, slower growth in demand reflects consumer disillusionment with just about every aspect of cell-phone service—its reliability, quality, and notorious customer service. The cooling off in demand threatens to cascade through the industry: The big six U.S. cell-phone carriers—Verizon Wireless, Cingular Wireless, AT＆T Wireless, Sprint PCS, Voice Stream, and Nextel Communications—are engaged in a fierce price war that imperils their timetables for becoming profitable, not to mention their efforts to whittle down their mountains of debt. As the carriers have begun to cut costs wireless equipment makers—companies such as Lucent, Nokia, and Ericsson have been left with a market that"s bound to be smaller than they had anticipated. Handset makers have been insulated so far, but they, too face a nagging uncertainty. They"ll soon introduce advanced phones to the U.S. market that will run on the new networks the carriers are starting up over the next year or two. But the question then will be: Will Americans embrace these snazzy data features and their higher costs—with the wild enthusiasm that Europeans and Asians have Long before the outcome in clear, the industry will have to adopt a new mind-set. "In the old days, it was all about connectivity." says Andrew Cole, an analyst with wireless consultancy Adventist. Build the network, and customers will come. From now on, the stakes will be higher. The new mantra: Please customers, or you may not survive. To work their way out of this box, the carriers are spending huge sums to address the problem. Much of Sprint PCS"s $3.4 billion in capital outlays this year will be for new stations. And in fact, the new high-speed, high-capacity nationwide networks due to roll out later this year should help ease the calling capacity crunch that has caused many consumer complaints. In the meantime, some companies are using better training and organization to keep customers happy. The nation"s largest rural operator, Alltel (AT), recently reorganized its call centers so that a customer"s query goes to the first operator who"s available anywhere in the country, instead of the first one available in the customer"s home area. That should cut waiting time to one minute from three to five minutes previously. According to the author, the cell-phone industry must adopt a mind-set in order to
Eight months after Sep. 11, it is becoming increasingly apparent that various arms of the US government had pieces of information that, if put together, might have provided sketchy advance warning of the terrorist strikes to come. The White House now acknowledges, that the CIA told President Bush in August that suspected members of A1 Qaeda had discussed the hijacking of airplanes. At the same time, FBI agents were increasingly suspicious of some Middle Eastern men training at US flight schools. Yet the US government didn"t pay attention to this information. "There are always these little indicators that come in—of one sort or another—that don"t get enough decibels to receive attention," say former CIA Director Stansfield Turner. "The possibility of a traditional hijacking—in the pre-9.11 sense—has long been a concern of the government," White House spokesman Ari Fleischer said. But "this was a new type of attack that was not foreseen." In deed, he said the warnings did not suggest commercial airliners would be used as missiles and that the general assumption was that any attack would occur abroad, not in the US. Still, the White House says it did quietly alert several government agencies to the threat. Meanwhile, FBI agents were getting hints of the terrible plot. A classified memo drafted by the bureau reportedly warned in blunt language that Osama bin Laden might be linked to Middle Eastern men taking lessons at US flight schools. Mr. Turner sees this as a painful and avoidable mistake. The basic reason for the lack of coordination and communication is "a very large intelligence bureaucracy that is very compartmentalized," says Charles Penia, a senior defense analyst at the Cato Institute. Today, the disclosures raise a crucial question: Have recent reforms boosted Washington"s ability to pull together information from its many agencies—and thus disrupt future attacks Indeed, since Sep. 11, the government has struggled to improve coordination. One change: FBI data is now merged with CIA intelligence in the president"s daily briefing. Another: A new command center near Washington was set up by White House Homeland Security. It"s one place the CIA, the FBI, the Defense Intelligence Agency, and others are able to coordinate and share information. It"s not clear yet whether they actually will. The government has made great effort to
Over the last twenty years, scholarly and popular writers have analyzed and celebrated the worlds of leisure and entertainment in the burgeoning cities of mid-nineteenth-century America, greatly expanding the literature on these subjects. They have found an enthusiastic readership by offering glimpses of modes of leisure, performance, and charlatanism that passed from the scene in the early 20th century, indicating how lively they were and how comparatively impoverished our own entertainment choices have become in an era dominated by corporate electronic media. Many scholars have been lured into a fascination with the extinct demimonde of dime museums, exhibition hails, saloons, and industrial exhibitions. During this period entertainment relied upon artful deception, comparable in importance to such contemporary forms of amusement as minstrelsy and melodrama. The cultural activities were forms of representational play in which spectators are caused to doubt their perceptions and judgment. Entertainments that tricked, or duped the paying public flourished in America"s cities in the 19th century. What distinguished these cohorts of entertainers, was not their ability to perpetrate fraud but that they understood the dynamics of a new urban audience that enjoyed distinguishing the genuine from the fake and the authentic from the concocted. The willing audience for artful deceptions maintained a double consciousness in which it simultaneously marveled at the qualities of the object or action displayed while enjoying the act of appraising the quality, audacity, and performance of the deception. By offering semiotic analyses of a range of Victorian performances, we learn there was more to these exhibitions than appeared at first viewing. The tricks and lures of these entertainers deserve a more than marginal position in American cultural history. We can infer that entertainment in 1845 was based on
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