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[阅读小分队] 【每日阅读训练第四期——速度越障19系列】【19-14】科技

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发表于 2013-5-29 08:08:01 | 显示全部楼层 |阅读模式
大家好,不好意思,今天早上才发!今天的速度文章主要是生物类的,越障的有点不同,预示着未来的一个发展方向~
Part I: Speed
[Time 1]
Article 1
The Dog or the Wolf?
WASHINGTON, D.C.—Since they split from wolves, domestic dogs have changed in many ways. Unlike their wild ancestors, they're comfortable around humans, pay close attention to us, and follow orders—at least sometimes. That social intelligence is critical to making a dog man's best friend. But research presented here last week at the annual meeting of the Association for Psychological Science shows that dogs may have also lost some of their social smarts in the process.

One of the classic experiments that shows the cognitive difference between wolves and dogs is the pointing task: Whereas a dog—even a 3-month-old puppy—will readily follow the direction a person points in, wolves just don't get it. That contrast has been cited as evidence that dogs may have gained social intelligence not present in wolves. "But that story is too simple," says Friederike Range, a behavioral biologist at the University of Veterinary Medicine Vienna.

To dig deeper, Range and her colleague Zsófia Virányi studied a captive population of wolves and dogs raised together at the Wolf Science Center outside Vienna. For one thing, they found that wolves work together better than dogs do. For example, in one set of experiments that have not been published, Range and Virányi observed the behaviors of groups of wolves or dogs sharing a common food source provided by researchers. Although there was more aggression among wolves—from muzzle-nipping to growling—every wolf, even the lowest ranked, was able to negotiate a share of food. Dogs are less aggressive with one another, but the food-sharing is far from collaborative. "The alpha dog monopolizes the food source and lower ranked dogs just stay away," Range says. Those differences made Range and Virányi wonder: Perhaps scientists who compare the social intelligence of wolves and dogs have been barking up the wrong tree. Dogs may be better at learning from humans, but what about from other dogs?

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[Time 2]

To test how well dogs and wolves could learn from one another, the researchers created a problem that wolves and dogs were equally motivated to solve: a food treat locked inside a box. The only way to open the box was with a lever. They trained one dog to operate the lever with its mouth, and another dog to use its paw. (The wolves were raised with the dogs and treated them as members of the same pack, Range says.) Then they let wolves and dogs see the box opened by one of those two methods. If dogs have better social intelligence across the board, they should do better than the wolves at learning by example and getting at the treat.

But the dogs did poorly, Range reported at the meeting. Only four out of 15 managed to open the box at all, and none used the method (mouth or paw) that they had been shown. Meanwhile, all 12 of the wolves got the treat, and nine of them did so by copying the method they had been shown. "The mainstream theory is that wolves became dogs when they started treating humans as their pack members," Range says. Rather than gaining new cognitive abilities that wolves never had, such as so-called "theory of mind" required to learn complex tasks by watching others perform, dogs may have undergone an evolutionary tradeoff: losing some of the ability to learn from their own kind, but gaining the ability to learn from humans.

The jury is still out on whether dogs have lost a mental ability. "What we need to see next is the same experiment but with humans teaching the dogs and wolves," says Timothy Bates, a psychologist at the University of Edinburgh in the United Kingdom. It may be that dogs have grown worse at learning, but "it could be that dogs just pay attention only to humans now." Range says that she has done the experiment to test that difference and is analyzing the data now.

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[Time 3]
Article 2
Immunotherapy’s cancer remit widens
Combination therapies hold great promise, but at what cost?
Drugs that unleash the power of the immune system on cancers are generating considerable optimism in industry, but still Andrew Baum thinks analysts are selling them short. In a 22 May report, Baum, the London-based head of global health-care research at the investment bank Citi, forecasts that in ten years the drugs will be treating 60% of cancers and earning US$35 billion a year.

Three elements contribute to his bullishness: the drugs are showing signs of wider effectiveness; many patients will take them for years; and the prices are stratospheric.

One of the first such drugs to be approved, Yervoy (ipilimumab), costs about $40,000 per month in the United States, and £15,000 ($23,000) in the United Kingdom, where health-care officials negotiated a lower price. So far, expensive immunotherapies have been approved only for treating melanoma and prostate cancer. But this weekend, at the annual meeting of the American Society of Clinical Oncology in Chicago, Illinois, investigators will present promising results from trials that indicate that immunotherapies could soon have a role in treating cancers of the lung, kidney and stomach.

A new strategy will add to the costs: regimens that combine the drugs with radiation therapy, genetically targeted drugs and other immunotherapies. The hope is that these other treatments will enhance the ability of the immune system to recognize the tumour, either by further stimulating the immune system, or by damaging the tumour so as to release antigens that the immune system recognizes.

Yervoy, made by Bristol-Myers Squibb, headquartered in New York, is remarkable because a three-month course can send cancer into remission for years (see go.nature.com/k1e3m2). However, only about one-quarter of patients with advanced melanoma responds to the drug, which spurs tumour-killing T cells into action by blocking an inhibitory signal. “When Yervoy was first approved in 2011, we all recognized that it was an important moment for the field,” says Jedd Wolchok, an oncologist at the Memorial Sloan-Kettering Cancer Center in New York. “But it was also a call to do better.”

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[Time 4]

On 2 June, Wolchok will present data from a trial that combined Yervoy with an experimental drug called nivolumab, also made by Bristol-Myers Squibb. It releases a second brake on the immune system by stifling a different protein. The number of patients in the trial was small, but the results suggest that melanomas shrank in half of those who received the highest two doses tested.

Combination approaches could expand the number of cancers that respond to immunotherapy. But they could also accelerate the rise in the cost of cancer care. US spending on cancer drugs is rising by some 15% a year, twice as fast as heath-care costs overall. “Cancer is a very complicated and expensive disease,” says Scott Ramsey, a health-care economist at the Fred Hutchinson Cancer Research Center in Seattle, Washington. “But now it’s turning into a chronic disease, and we’re talking about years of maintenance therapy with drugs that cost $10,000 a month.” However, not all of the inflation is due to expensive new drugs, says Ira Klein, a medical director at insurance company Aetna, based in Hartford, Connecticut. The price of radiation therapy is rising by 25% per year, he notes, driven by new technologies that can cost $100,000 or more for a full course of treatment.

Drug developers attribute the high cost of the drugs to the expense of research and development, which is compounded by the industry’s high failure rate. Wolchok notes that drugs such as Yervoy have a small market, and speculates that prices may fall once their markets expand to other cancers. But Peter Bach, who studies health-care policy at Memorial Sloan-Kettering, is sceptical that industry will cut prices. “I have never seen that,” he says. “I have only seen the opposite.”

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[Time 5]
Article 3
Frozen Plants Come Back to Life After Hundreds of Years
A group of plants frozen inside Teardrop Glacier in the Canadian Arctic for more than 400 years still has the ability to grow and reproduce, scientist have discovered. In 2007, researchers were collecting long-frozen plant samples from the receding edges of the glacier when they noticed some bryophytes—plants which include mosses and mosslike liverworts—sprouting new parts (as seen in the main image). They dated a subset of the bryophytes and found that the plants ranged in age from 404 to 614 years old, confirming that were frozen during the Little Ice Age, a period of cooling lasting a few hundred years, which ended in the 19th century. In the lab, the researchers were able to regrow bryophyte samples representing four different taxa from the glacier, they report online today in the Proceedings of the National Academy of Sciences (inset). The finding suggests that bryophytes are more resilient than was previously known, the authors say, and likely play a role in the early recolonization of areas revealed by glacier melt, such as those in the Canadian and Alaskan Arctic.

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Part II: Obstacle
Article 4
3-D printed windpipe gives infant breath of life
A flexible, absorbable tube helps a baby boy breathe, and heralds a future of body parts printed on command.
Kaiba Gionfriddo was six weeks old when he suddenly stopped breathing and turned blue at a restaurant. Kaiba’s parents quickly rushed him to the hospital where they learned that his left bronchial tube had collapsed because of a previously undetected birth defect. During the next few weeks the life-threatening attacks recurred, increasing in number until they became everyday events. Physicians and researchers, however, used some of the most sophisticated bioengineering techniques available to 3-D print a synthetic tube to hold the baby's airway open. Kaiba had the surgery in January 2012 and hasn’t suffered an airway collapse since.

The trachea, or windpipe, is essentially constructed much like a vacuum cleaner hose, says Glenn Green, an ear nose and throat specialist (otolaryngologist) at the University of Michigan, who helped to develop the device. The human trachea comprises 20 rings of cartilage linked by muscle and connective tissue that extends from the Adam's apple down behind the breastbone. It then branches into two tubes called bronchi that each connect to a lung. With each inhalation, the lungs fill and expand; likewise, the strong but flexible airway tubes widen and lengthen.

In most cases after a child is born, the cartilage in the trachea keeps the airway open. But in about one out of 2,100 live births, for some reason, a portion of the airway is floppy and collapses, blocking outside air from reaching one or both lungs. Treatment for this kind of condition—called an airway malacias—includes close monitoring during colds and other respiratory infections, but some people may need a respirator to keep their airways open or surgery to insert a breathing tube until the danger has passed. Surgical treatments for persistent cases include using a structure inside the airway to prop it open—a stent—but that approach irritates the trachea, says John Bent, an associate professor at the Albert Einstein College of Medicine and director of pediatric otolaryngology at Montefiore Medical Center in New York City. Or doctors may take a piece of the patient's rib and use it around the outside of the trachea as a splint. "But that doesn't give [the airway] the right shape," he says, or the ability to expand and contract with each breath.

For unknown reasons, however, some cases are extremely severe. Those infants, including Kaiba, struggle to breathe even after treatment.
Fresh out of options, Kaiba’s doctors contacted Green and his colleagues who were working on a new device that could help. The researchers had been searching for a way to help infants with collapsing airways. They designed a tube that could wrap around the floppy portion of a trachea or bronchus and hold the airway open. Each individual's airway, however, is unique, and there is no one-size-fits-all solution. Instead Green and his colleagues would create custom-designed devices using technology called three-dimensional printing.

A 3-D printer works like an inkjet printer, but instead of laying down layers of ink it deposits a structural material. The printer head adds each layer according to a digital pattern to create a 3-D structure. 3-D printers in manufacturing have built prototypes and parts for machines. In research settings bioengineers have created artificial ears, and lab rats have received printed spinal disks and bones. Printing fully functioning organs and tissues for humans poses some challenges. A kidney, for example, needs working blood vessels and tubes to collect urine.

Problems with the trachea, however, lend themselves to 3-D printed solutions because the organ's ridged tubelike structure is simple. After testing their idea in piglets, Green and his colleagues were confident a printed device would work. Scott Hollister, a professor of biomedical engineering at Michigan was in charge of designing sleeve that would wrap around the outside of the floppy airway. The sleeve's structure allows it to expand as the airway grows and develops while simultaneously resisting spasms that pull inward, thereby collapsing the airway.

The team first used a computed tomography (CT) scan to sketch out Kaiba’s airways. From those images, they then sculpted a three-dimensional printed cast that had the same shape as Kaiba’s collapsed bronchus. Using that cast they created the sleeve or splint that would wrap around the bronchus. It took several tries but the researchers were eventually able to create a perfect fit. The next step was to sew the tissue of Kaiba’s bronchus to the inside of the sleeve. The team needed to obtain an emergency-use approval from the U.S. Food and Drug Administration before they could implant the device. "When we put the splint on, we saw his lungs move for the first time," Green says. As Kaiba grows, the device should expand with him.

The tube itself was printed in layers of a biocompatible plastic called polycaprolactone. The 3-D printer heats up a powdered form of the plastic until it melts and can be extruded in a paste. After a few years inside a body the tube will dissolve—it is made of the same material used for sutures—and by that time his bronchus should have grown strong enough to function normally.

Kaiba’s tube is the first time a 3-D printed device has been implanted in a patient to aid tissue reconstruction. The research team reported the case on May 22 in The New England Journal of Medicine.

"It's a very nice approach to using technology to treat a problem that has not a lot of good solutions," says Robert Weatherly, an associate professor of otolaryngology at the University of Kansas School of Medicine and a physician at Children's Mercy Hospital in Kansas City, Mo., who was not involved in the study. He points out that the approach is different from a typical tissue engineering approach because Kaiba’s bronchus tissue was present but not functioning; here the 3-D device reinforces underdeveloped tissue. In other cases tissue is absent and needs to be rebuilt from scratch—as in a recent case of a young girl with an absent trachea. Her doctors built a transplantable trachea of plastic incubated with the child's own stem cells. Unlike Kaiba, however, she will need a bigger windpipe when she grows.

The critical next steps to making the technology more available are clinical trials, along with tracking patients over a longer period of time to see how they fare with 3-D printed parts.

The use of 3-D printed devices and body parts is still in its infancy. Cartilage and bone will be the first solutions to reach wide use, Green says, adding there is a "gigantic potential," for the future.

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发表于 2013-5-29 08:41:46 | 显示全部楼层
铁板家族来了~~

02:02
02:07
02:36
01:25
01:10
04:04 好强大的3D印刷制品,是先天气管下垂或者堵塞儿童的福音


发表于 2013-5-29 08:42:14 | 显示全部楼层
嘿 我拿到首页了!
---------------------------------------------------
1'30''
1'30''
1'50''
1'20''
1'00''

6'02''
发表于 2013-5-29 08:49:58 | 显示全部楼层
铁板神猴 发表于 2013-5-29 08:42
嘿 我拿到首页了!

恭喜

微博广告都做到CD签名来了。。要不要我们铁板家族给你宣传一下!
发表于 2013-5-29 08:51:54 | 显示全部楼层
Day day up! 首页占座做作业。

谢谢翔翔的文章,越障题材比较偏,估计其他队友看着会有点吃力(单词)。

来来来,科普:


Time1 1'25"
Time2 1'20"
Time3 1'32"
Time4 1'27"
Time5 43"
Obstacle 4'59"
发表于 2013-5-29 09:03:33 | 显示全部楼层
占座

1:31 Finding behavior pattern’s about thedifferent between dogs and wolves. Dog’s behavior is much more effected bypeople and less effected by themselves.
1:39 Dogs have an evolutionary tradeoff: losingintelligent of studying, but gaining the ability of attention to humans.
1:22 The medical drug industry for immune system on cancers is a big business.
1:14 How to cut the high price of drugs which treatthe cancer.
0:48 Frozen plants inside glacier also can survive.
5:12 How to usenew technology about 3-D printed devices to survive infants from no breathing.

哈哈,我归队了, 谢谢神猴热情招待哈!
发表于 2013-5-29 09:18:43 | 显示全部楼层
草莓葡萄 发表于 2013-5-29 09:03
占座

咦 草莓葡萄好久不见啊 回归了
发表于 2013-5-29 09:22:29 | 显示全部楼层
2.13
Dogs and wolves, dogs' wild ancestors have chenged. Dogs gain more social intelligence, however, wolves' prepondence is working together.
2.26
Test
Dogs learn much better from human than from their kind.
Wolves is strong at learn new by watching other.
New Test
2.08
1.43 cost of cancer
1.28 plant dead in ice age regrow after hundre years later

6.57
发表于 2013-5-29 09:25:06 | 显示全部楼层
一个不小心 原来我在首页呀
发表于 2013-5-29 09:26:37 | 显示全部楼层
1 02:27 Previous & present research on social intelligence of dogs and wolves.
2 02:01 Further experiment on social intelligence: dog learns better from human than from other dogs.
3 02:14 A forecast of sale of cancer medicine and the grounds of the forecast. New strategy.
4 01:59 a new combination trial--increase the numbers of cancer patients respond to immunotherapy, but increase the cost of patients. The cost rise quickly, partly because the cost of radiation therapy. Different views of the tendence of the cost.
5 01:11 frozen plants can grow and reproduce: an example of b in 2007.

obstacle 07:19
a case of an infant who survived thanks to a new medical technology.
introduce of K's disease and the traditional and new therapy of this disease.
3-D printer's funtion during the process.
the process of the surgery.

今天的内容都比较有趣~辛苦楼主!~~
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