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Birds that are literally half-asleep—with one brain hemisphere alert and the other sleeping—control which side of the brain remains awake, according to a new study of sleeping ducks.Earlier studies have documented half-brain sleep in a wide range of birds. The brain hemispheres take turns sinking into the sleep stage characterized by slow brain waves. The eye controlled by the sleeping hemisphere keeps shut, while the wakeful hemisphere’s eye stays open and alert. Birds also can sleep with both hemispheres resting at once.Decades of studies of bird flocks led researchers to predict extra alertness in the more vulnerable, end-of-the-row sleepers. Sure enough, the end birds tended to watch carefully on the side away from their companions. Ducks in the inner spots showed no preference for gaze direction.Also, birds dozing at the end of the line resorted to single-hemisphere sleep, rather than total relaxation, more often than inner ducks did. Rotating 16 birds through the positions in a four-duck row, the researchers found outer birds half-asleep during some 32% of dozing time versus about 12% for birds in internal spots."We believe this is the first evidence for an animal behaviorally controlling sleep and wakefulness simultaneously in different regions of the brain," the researchers say.The results provide the best evidence for a long-standing supposition that single-hemisphere sleep evolved as creatures scanned for enemies. The preference for opening an eye on the lookout side could be widespread, he predicts. He’s seen it in a pair of birds dozing side-by-side in the zoo and in a single pet bird sleeping by a mirror. The mirror-side eye closed as if the reflection were a companion and the other eye stayed open.Useful as half-sleeping might be, it’s only been found in birds and such water mammals as dolphins, whales, and seals. Perhaps keeping one side of the brain awake allows a sleeping animal to surface occasionally to avoid drowning.Studies of birds may offer unique insights into sleep. Jerome M. Siegel of the UCLA says he wonders if birds’ half-brain sleep "is just the tip of the iceberg". He speculates that more examples may turn up when we take a closer look at other species. While sleeping, some water mammals tend to keep half awake in order to ().
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M: When my brother Dan was diagnosed with brain cancer in 2001 and was told he likely had less than a year to live, my family was in complete shock. We immediately started asking questions, many of which went unanswered because there was either no relevant information available (including what causes brain cancer) or conflicting information (including how to treat it). In the middle of our horrific family crisis, we didn’t know who to believe or what we could do. It was this firsthand experience, along with the everyday health issues that all families face, that made me realize that even though the US has some of the best doctors in the world, our nation’s health care system is broken and desperately needs to be fixed. Indeed, even calling it "health care" is somewhat misleading. Given that an estimated 98% of spending goes toward treating illness and only about 2% toward prevention and wellness, it would be more accurate to refer to it as the "sick care" system.From my own personal experience, I’ve discovered that the complex maze of paperwork, uncertainty and confusion that marks today’s health care system are merely symptoms of a much larger illness that affects millions of consumers. The fundamental issue is that, at least in America, the nation’s current health care model does not engage consumers to better manage their own health.One way to cure this is people to make efforts to stay healthy. In the "staying healthy" industry, consumers today spend billions of dollars a year on gym memberships, fitness gear, fruits and vegetables, massages, acupuncture and personal trainers. This broad and diverse industry allows consumers to pick and choose from a variety of providers who are competing for their business. These businesses have to offer clear transparency, competitive prices and superior quality.But something happens when you get a cold, or worse, and are plunged into the black hole of co-payments, insurance claims, preset doctor lists, HMOs, PPOs--and utter dysfunction.The problem is that when most consumers get sick, employers and insurance companies usually pick up the tab. Meanwhile, the consumer is caught in the middle while these two competing forces try to minimize their expenditures. Most of the time, consumers have no idea how much their procedures cost, nor do they care--they’re focused more on their own modest co-pay.Though the challenges of the health care system seem daunting, I see two key trends that will cause major changes to the industry.The first is the shifting financial burden for health coverage to employees. Consumers are now paying more for their health coverage, which means they are demanding more in return. It’s simple economics that if people are paying extra, they will want a bigger role in the decisions about their health care.The second trend is the increasing number of consumers who are concerned about living healthier lives. This is proved by their increased spending in the "staying healthy" industry. Not only are they buying, but consumers are also looking for more information about how to improve their health, fitness and wellness.These trends and my own personal experiences with the health care industry motivated me to create Revolution Health with the hope that we could help produce a shift to a new system driven by consumers, shaped by market forces and powered by technology.Some say health care will never change because consumers tend to be passive about their health. But I truly believe people will be more responsible for improving their health--they just need to be empowered and given tools to make better choices. Uncertainty is the fundamental problem of American health care system.
M: When my brother Dan was diagnosed with brain cancer in 2001 and was told he likely had less than a year to live, my family was in complete shock. We immediately started asking questions, many of which went unanswered because there was either no relevant information available (including what causes brain cancer) or conflicting information (including how to treat it). In the middle of our horrific family crisis, we didn’t know who to believe or what we could do. It was this firsthand experience, along with the everyday health issues that all families face, that made me realize that even though the US has some of the best doctors in the world, our nation’s health care system is broken and desperately needs to be fixed. Indeed, even calling it "health care" is somewhat misleading. Given that an estimated 98% of spending goes toward treating illness and only about 2% toward prevention and wellness, it would be more accurate to refer to it as the "sick care" system.From my own personal experience, I’ve discovered that the complex maze of paperwork, uncertainty and confusion that marks today’s health care system are merely symptoms of a much larger illness that affects millions of consumers. The fundamental issue is that, at least in America, the nation’s current health care model does not engage consumers to better manage their own health.One way to cure this is people to make efforts to stay healthy. In the "staying healthy" industry, consumers today spend billions of dollars a year on gym memberships, fitness gear, fruits and vegetables, massages, acupuncture and personal trainers. This broad and diverse industry allows consumers to pick and choose from a variety of providers who are competing for their business. These businesses have to offer clear transparency, competitive prices and superior quality.But something happens when you get a cold, or worse, and are plunged into the black hole of co-payments, insurance claims, preset doctor lists, HMOs, PPOs--and utter dysfunction.The problem is that when most consumers get sick, employers and insurance companies usually pick up the tab. Meanwhile, the consumer is caught in the middle while these two competing forces try to minimize their expenditures. Most of the time, consumers have no idea how much their procedures cost, nor do they care--they’re focused more on their own modest co-pay.Though the challenges of the health care system seem daunting, I see two key trends that will cause major changes to the industry.The first is the shifting financial burden for health coverage to employees. Consumers are now paying more for their health coverage, which means they are demanding more in return. It’s simple economics that if people are paying extra, they will want a bigger role in the decisions about their health care.The second trend is the increasing number of consumers who are concerned about living healthier lives. This is proved by their increased spending in the "staying healthy" industry. Not only are they buying, but consumers are also looking for more information about how to improve their health, fitness and wellness.These trends and my own personal experiences with the health care industry motivated me to create Revolution Health with the hope that we could help produce a shift to a new system driven by consumers, shaped by market forces and powered by technology.Some say health care will never change because consumers tend to be passive about their health. But I truly believe people will be more responsible for improving their health--they just need to be empowered and given tools to make better choices. The speaker thinks that people should pay less for health out of their own pockets.
M: When my brother Dan was diagnosed with brain cancer in 2001 and was told he likely had less than a year to live, my family was in complete shock. We immediately started asking questions, many of which went unanswered because there was either no relevant information available (including what causes brain cancer) or conflicting information (including how to treat it). In the middle of our horrific family crisis, we didn’t know who to believe or what we could do. It was this firsthand experience, along with the everyday health issues that all families face, that made me realize that even though the US has some of the best doctors in the world, our nation’s health care system is broken and desperately needs to be fixed. Indeed, even calling it "health care" is somewhat misleading. Given that an estimated 98% of spending goes toward treating illness and only about 2% toward prevention and wellness, it would be more accurate to refer to it as the "sick care" system.From my own personal experience, I’ve discovered that the complex maze of paperwork, uncertainty and confusion that marks today’s health care system are merely symptoms of a much larger illness that affects millions of consumers. The fundamental issue is that, at least in America, the nation’s current health care model does not engage consumers to better manage their own health.One way to cure this is people to make efforts to stay healthy. In the "staying healthy" industry, consumers today spend billions of dollars a year on gym memberships, fitness gear, fruits and vegetables, massages, acupuncture and personal trainers. This broad and diverse industry allows consumers to pick and choose from a variety of providers who are competing for their business. These businesses have to offer clear transparency, competitive prices and superior quality.But something happens when you get a cold, or worse, and are plunged into the black hole of co-payments, insurance claims, preset doctor lists, HMOs, PPOs--and utter dysfunction.The problem is that when most consumers get sick, employers and insurance companies usually pick up the tab. Meanwhile, the consumer is caught in the middle while these two competing forces try to minimize their expenditures. Most of the time, consumers have no idea how much their procedures cost, nor do they care--they’re focused more on their own modest co-pay.Though the challenges of the health care system seem daunting, I see two key trends that will cause major changes to the industry.The first is the shifting financial burden for health coverage to employees. Consumers are now paying more for their health coverage, which means they are demanding more in return. It’s simple economics that if people are paying extra, they will want a bigger role in the decisions about their health care.The second trend is the increasing number of consumers who are concerned about living healthier lives. This is proved by their increased spending in the "staying healthy" industry. Not only are they buying, but consumers are also looking for more information about how to improve their health, fitness and wellness.These trends and my own personal experiences with the health care industry motivated me to create Revolution Health with the hope that we could help produce a shift to a new system driven by consumers, shaped by market forces and powered by technology.Some say health care will never change because consumers tend to be passive about their health. But I truly believe people will be more responsible for improving their health--they just need to be empowered and given tools to make better choices. Transparency and quality are something desirable in the "staying healthy" industry.
World leaders met recently at United Nations headquarters in New York City to discuss the environmental issues raised at the Rio Earth Summit in 1992. The heads of state were supposed to decide what further steps should be taken to halt the decline of Earth’s life-support systems. In fact, this meeting had much the flavour of the original Earth Summit. To wit: empty promises, hollow rhetoric, bickering between rich and poor, and irrelevant initiatives. Think U.S. Congress in slow motion. Almost obscured by this torpor is the fact that there has been some remarkable progress over the past five years--real changes in the attitude of ordinary people in the Third World toward family size and a dawning realisation that environmental degradation and their own well-being are intimately, and inversely, linked. Almost none of this, however, has anything to do with what the bureaucrats accomplished in Rio. Or it didn’t accomplish. One item on the agenda at Rio, for example, was a renewed effort to save tropical forests. (A previous UN-sponsored initiative had fallen apart when it became clear that it actually hastened deforestation)After Rio, a UN working group came up with more than 100 recommendations that have so far gone nowhere. One proposed forestry pact would do little more than immunizing wood-exporting nations against trade sanctions. An effort to draft an agreement on what to do about the climate changes caused by CO2 and other greenhouse gases has fared even worse. Blocked by the Bush Administration from setting mandatory limits, the UN in 1992 called on nations to voluntarily reduce emissions to 1990 levels. Several years later, it’s as if Rio had never happened. A new climate treaty is scheduled to be signed this December in Kyoto, Japan, but governments still cannot agree on these limits. Meanwhile, the U. S. produces 7% more CO2 than it did in 1990 ,and emissions in the developing world have risen even more sharply. No one would confuse the "Rio process" with progress. While governments have dithered at a pace that could make drifting continents impatient, people have acted. Birth-rates are dropping faster than expected, not because of Rio but because poor people are deciding on their own to reduce family size. Another positive development has been a growing environmental consciousness among the poor. From slum dwellers in Karachi, Pakistan, to colonists in Rondonia, Brazil ,urban poor and rural peasants alike seem to realize that they pay the biggest price for pollution and deforestation. There is cause for hope as well in the growing recognition among business people that it is not in their long-term interest to fight environmental reforms. John Browne, chief executive of British Petroleum, boldly asserted in a major speech in May that the threat of climate change could no longer be ignored. Which of the following best summarizes the text().
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