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[阅读小分队] 【每日阅读训练第四期——速度越障2系列】【2-12】经管

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发表于 2012-6-1 21:25:57 | 显示全部楼层 |阅读模式
各位亲耐滴的大朋友们,六一快乐哟~~~
大家继续加油哇!!马力十足地加油!!!

【速度】
Will we ever… clone a mammoth?

【计时1】

Bringing the prehistoric animal back to life will require dexterity with DNA, a slice of luck and an intimate knowledge of an elephant’s reproductive system.

Tens of thousands of years ago, woolly mammoths roamed the northern hemisphere. These giant beasts may now be extinct, but some of their bodies still remain in the frozen Arctic wilderness. Several dozen such carcasses have now been found, and some are in extremely good condition. Scientists have used these remains to discover much about how the mammoth lived and died, and even to sequence most of its genome. But can they also bring the animal back from the dead? Will the woolly mammoth walk again?

Akira Iritani certainly seems to think so. The 84-year-old reproductive biologist has been trying to clone a mammoth for at least a decade, with a team of Japanese and Russian scientists. They have tried to use tissues from several frozen Siberian specimens including, most recently, a well-preserved thighbone. Last year, Iritani told reporters, "I think we have a reasonable chance of success and a healthy mammoth could be born in four or five years.”

A few months ago, a second team led by Korean scientist Hwang Woo Suk also expressed interest in cloning a mammoth. While Iritani comes with impressive credentials, Hwang’s resume is less reassuring. He is perhaps best known for faking experiments in which he claimed to have cloned the first human embryo and produced stem cells from it. The fact that he has confessed to buying mammoth samples from the Russian mafia does not help to instil confidence.

【262 words】

【计时2】

Regardless of their pedigree, both teams have their work cut out. Any attempt to resurrect the mammoth faces an elephantine gauntlet of challenges, including the DNA-shattering effects of frost and time, and the rather unhelpful reproductive tract of the eventual surrogate parent—the elephant.

Gene challenge

Siberian ice might preserve the bodies of mammoths, but it is not kind to them. Ice crystals puncture cells, spilling out their contents. Even if the DNA inside the cell is not exposed, it tends to break down over time. Stephan Schuster from Penn State University, who led the mammoth sequencing project, says, “Even the genomes from much younger organisms rapidly decay. It’s like smashing a mirror on the floor.” Schuster’s team compared the heavily fragmented DNA of a mammoth against the genome of an elephant. That approach allowed them to read the genome, but it cannot be used to reconstruct it.

Synthesising an animal genome from scratch is a massive challenge by today’s technological standards. It would require: a far more accurate draft than the one we have; knowledge of the number of chromosomes a mammoth had; the ability to stitch together such large stretches of DNA; ways of packaging that DNA into a nucleus; and hoping that all the DNA will still be in good working order.

There is another option. Rather than producing mammoth DNA from scratch, you could tweak DNA from an African elephant. The genomes of the two species differ by just 0.6 percent, half the difference between us and chimpanzees. By identifying and swapping the different sequences, you could potentially rewrite an elephant genome so that it reads like a mammoth one.

【274 words】

【计时3】

Palaeontologist Jack Horner is trying something similar by rolling back a chicken’s genes into a state more like its extinct dinosaur ancestors, and scientists like Harvard University’s George Church are developing techniques that can rewrite vast swathes of DNA at once. But even if the technology catches up with the ambition, Schuster says: “That’s not making a mammoth. It’s ‘mammothifying’ an elephant.” The resulting creature may be a more mammoth-like version of today’s pachyderms, but it won’t be the real deal.

These problems might be avoided if we could find intact nuclei from frozen mammoths, at least if experiments in other animals are anything to go by. In 2008, Sayaka Wakayama and colleagues from RIKEN, Japan cloned healthy mice from individuals that had been frozen for 16 years. They found intact nuclei in the chilled bodies, and fused them with empty eggs. By all accounts, Iritani is trying to do the same thing with frozen mammoth remains (he did not respond to a request for an interview). But Schuster does not mince words about the odds of finding intact mammoth nuclei. “It’s entirely impossible,” he says. Sixteen years in the freezer is one thing; 16,000 years is quite another.

Pregnant pause

Assuming that Iritani’s team gets an intact nucleus, they would still have to insert it inside an elephant egg. Collecting such an egg means navigating a reproductive tract that spans three metres from the uterus to the outside world. “It’s extremely challenging,” says Thomas Hildebrandt from the Leibniz Institute for Zoo and Wildlife Research, who knows the reproductive tract of elephants like the length of his arm.

【268 words】

【计时4】

A female elephant only ovulates once every five years, releasing one or two eggs at any time to ensure that she never becomes pregnant with several gargantuan foetuses. Each egg is a 2-centimetre-wide ball rattling around an enormous cavern. Once it is released, the female almost immediately has sex. “There are almost no wild elephants that are fertile without already being pregnant,” says Hildebrandt. So, collecting an oocyte from an elephant is like groping in a haystack for a needle that probably does not exist. If getting one egg sounds hard enough, would-be mammoth-makers need hundreds or thousands of eggs to ensure one successful clone.

There is a possible cheat. They could take ovarian tissue from a culled elephant, transplant it into a rat or a mouse, and tweak the rodent’s hormonal cycles to ensure that the eggs mature properly. This has been tried, but no one knows if the resulting eggs were actually viable. It’s a long shot, and “you still have the problem of transplanting the embryo,” says Hildebrandt.

Notwithstanding the distance into the uterus, the path is blocked by the hymen. This is essential to the elephant; it grows back after every birth and it cannot be broken without compromising the pregnancy. It has an opening just 2 to 4 millimetres wide that allows passage to sperm – that’s what an embryo-carrying tube would have to navigate through. “It’s not impossible but it would need quite a lot of technological development,” says Hildebrandt. “Most people don’t expect that. They think they biggest challenge is creating the embryo.”

Even if a baby mammoth comes to term, it may not last for long. In 2009, European scientists used preserved skin cells to clone the Pyrenean ibex, a type of goat that had been extinct since 2000. The glorious resurrection lasted all of seven minutes, before the newborn kid died of lung failure. Many (but far from all) cloned animals have suffered from similar health problems. If the woolly mammoth does the same, its resurrectors could end up with the world’s most expensive carcass.

【343 words】

【计时5】

Conservation boost

Despite these many hurdles, Schuster does not dismiss the possibility of cloning a mammoth, especially with improvements in genetic techniques. “Every time a journalist asks me about this, one of those hurdles has been taken out,” he says. “I think it’s a little irresponsible to stand there and say it’ll never happen, but that doesn’t mean we should spend money on it. Maybe it would be better spent on preserving endangered species today.”

Can we really justify trying to bring the mammoth back from extinction when all three species of living elephant are in danger of joining it? “If you’d interviewed me two or three years, ago, I would have been much more aggressive against it,” says Hildebrandt. He has changed his mind after struggling with efforts to conserve other large animals like the Sumatran rhino. Only a few hundred remain, and many are so old that no amount of assisted reproduction will help them to breed. “Our only option is to clone them,” he says.

Mammoth-cloning projects might act as an attractive funding magnet in a way that conservation projects of little-known rhinos cannot. “The mammoth may be able indirectly help future conservation projects, by developing cloning technologies that could help modern species,” says Hildebrandt. It’s a sobering thought: as impossible as cloning an extinct animal might sound, the one good reason to try is that it might prevent a number of species from suffering the same fate.

【241 words】

【越障】

Robot ethics
Morals and the machine

As robots grow more autonomous, society needs to develop rules to manage them

IN THE classic science-fiction film “2001”, the ship’s computer, HAL, faces a dilemma. His instructions require him both to fulfil the ship’s mission (investigating an artefact near Jupiter) and to keep the mission’s true purpose secret from the ship’s crew. To resolve the contradiction, he tries to kill the crew.
As robots become more autonomous, the notion of computer-controlled machines facing ethical decisions is moving out of the realm of science fiction and into the real world. Society needs to find ways to ensure that they are better equipped to make moral judgments than HAL was.

A bestiary of robots

Military technology, unsurprisingly, is at the forefront of the march towards self-determining machines. Its evolution is producing an extraordinary variety of species. The Sand Flea can leap through a window or onto a roof, filming all the while. It then rolls along on wheels until it needs to jump again. RiSE, a six-legged robo-cockroach, can climb walls. LS3, a dog-like robot, trots behind a human over rough terrain, carrying up to 180kg of supplies. SUGV, a briefcase-sized robot, can identify a man in a crowd and follow him. There is a flying surveillance drone the weight of a wedding ring, and one that carries 2.7 tonnes of bombs.

Robots are spreading in the civilian world, too, from the flight deck to the operating theatre. Passenger aircraft have long been able to land themselves. Driverless trains are commonplace. Volvo’s new V40 hatchback essentially drives itself in heavy traffic. It can brake when it senses an imminent collision, as can Ford’s B-Max minivan. Fully self-driving vehicles are being tested around the world. Google’s driverless cars have clocked up more than 250,000 miles in America, and Nevada has become the first state to regulate such trials on public roads. In Barcelona a few days ago, Volvo demonstrated a platoon of autonomous cars on a motorway.

As they become smarter and more widespread, autonomous machines are bound to end up making life-or-death decisions in unpredictable situations, thus assuming—or at least appearing to assume—moral agency. Weapons systems currently have human operators “in the loop”, but as they grow more sophisticated, it will be possible to shift to “on the loop” operation, with machines carrying out orders autonomously.

As that happens, they will be presented with ethical dilemmas. Should a drone fire on a house where a target is known to be hiding, which may also be sheltering civilians? Should a driverless car swerve to avoid pedestrians if that means hitting other vehicles or endangering its occupants? Should a robot involved in disaster recovery tell people the truth about what is happening if that risks causing a panic? Such questions have led to the emergence of the field of “machine ethics”, which aims to give machines the ability to make such choices appropriately—in other words, to tell right from wrong.

One way of dealing with these difficult questions is to avoid them altogether, by banning autonomous battlefield robots and requiring cars to have the full attention of a human driver at all times. Campaign groups such as the International Committee for Robot Arms Control have been formed in opposition to the growing use of drones. But autonomous robots could do much more good than harm. Robot soldiers would not commit rape, burn down a village in anger or become erratic decision-makers amid the stress of combat. Driverless cars are very likely to be safer than ordinary vehicles, as autopilots have made planes safer. Sebastian Thrun, a pioneer in the field, reckons driverless cars could save 1m lives a year.

Instead, society needs to develop ways of dealing with the ethics of robotics—and get going fast. In America states have been scrambling to pass laws covering driverless cars, which have been operating in a legal grey area as the technology runs ahead of legislation. It is clear that rules of the road are required in this difficult area, and not just for robots with wheels.

The best-known set of guidelines for robo-ethics are the “three laws of robotics” coined by Isaac Asimov, a science-fiction writer, in 1942. The laws require robots to protect humans, obey orders and preserve themselves, in that order. Unfortunately, the laws are of little use in the real world. Battlefield robots would be required to violate the first law. And Asimov’s robot stories are fun precisely because they highlight the unexpected complications that arise when robots try to follow his apparently sensible rules. Regulating the development and use of autonomous robots will require a rather more elaborate framework. Progress is needed in three areas in particular.

Three laws for the laws of robotics

First, laws are needed to determine whether the designer, the programmer, the manufacturer or the operator is at fault if an autonomous drone strike goes wrong or a driverless car has an accident. In order to allocate responsibility, autonomous systems must keep detailed logs so that they can explain the reasoning behind their decisions when necessary. This has implications for system design: it may, for instance, rule out the use of artificial neural networks, decision-making systems that learn from example rather than obeying predefined rules.

Second, where ethical systems are embedded into robots, the judgments they make need to be ones that seem right to most people. The techniques of experimental philosophy, which studies how people respond to ethical dilemmas, should be able to help. Last, and most important, more collaboration is required between engineers, ethicists, lawyers and policymakers, all of whom would draw up very different types of rules if they were left to their own devices. Both ethicists and engineers stand to benefit from working together: ethicists may gain a greater understanding of their field by trying to teach ethics to machines, and engineers need to reassure society that they are not taking any ethical short-cuts.

Technology has driven mankind’s progress, but each new advance has posed troubling new questions. Autonomous machines are no different. The sooner the questions of moral agency they raise are answered, the easier it will be for mankind to enjoy the benefits that they will undoubtedly bring.

【1042 words】
发表于 2012-6-1 21:28:50 | 显示全部楼层
借宝地一坐~
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1'16''
1'28''
1'30''
2'15''
1'42''

6'42''
发表于 2012-6-1 21:29:35 | 显示全部楼层
板凳。。
发表于 2012-6-1 21:39:10 | 显示全部楼层
地板

1'24 In arctic wilderness, scientists found the frozen sample of mammoth and some persons want to clone mammoth. I taken the impressive result, but H didn't bring the actual research.
1'48 clone mammoth is difficult depand on current technology. first, recgonize the gene line is not easy, and combine them also hard because mammoth' gene is similiar with Africa elephants' gene.
1'50 even now we have the skills to rewrite the DNA line, but clone mammoth is not still hard as the cloned creature may dislike the actual ones. Japan cloned the mice from frozen 16 month egg, but it's a different thing to clone mammoth existed thousand years ago.
2'09 an elephant have baby is not very easy, so hard for the clone. another difficulty is present and even if the baby mammoth could successful born, it can't live for long.
1'14 someone challenge this progrom by saying that the money should be paid to protect current endangered animals. but those researchers said their work is just to do the clone.
6'30
first author introduced a movie to show the delima between the morals and the robot.
second, the author listed may samples to show the convinience the automachine brought, and slso pointed out many disadvances the robots have. From the mailitary area, auto cars industry to the monitor purpose.
and the author also mentioned the only law of robots, saying not to apply in real world.
Finally, author suggested that three laws should be worked out to limit the three group people and provided the reason. the moral standard embedded in robots should be agreed by most people. if we could solve the problem which robot brought quickly, we would enjoy the happiness early.
发表于 2012-6-1 21:42:25 | 显示全部楼层
54'
1:09
1:08
1:21
53'

4:45
好吧,越障没怎么看进去,基本上是当作速度来做的...
Robot or anatonmous system with the ethinics
发表于 2012-6-1 22:30:42 | 显示全部楼层
速度:
1'12    1'06    1'13     1'28    1'20
越障:6'02(弱弱的问一下,现在越障是不是一定要用英文了?)
Main idea:
Robots, just the same as other high-tech appliances, have posed troubles in their devloping process.
The author presents 3 key laws to deal with the ethtics problems of robots.

Structure:
1. indicate the ethtic problem of robots by illustrating a classical science fiction film.
2. present us the details occuring in the practical use of robots.
3. put forward 3 laws that can possibly solve the problem.
   (1)whether the designer or the manufacture are at fault.
   (2)the ethtic system embeded in robots must enable them to make right judgements.
   (3)the collaboration in the manufacturing the robots must assure that the combination of ethic system will go wrong.
发表于 2012-6-1 23:12:17 | 显示全部楼层
1.18
1.43
1.39
2.28
1.34

6.56
机器人的道德困境,列了现实中几种机器人的运用,但也说了可能的一些困境,所以在很多地方都禁止机器人在交通的运用,但实际上它们带来的好处是大于坏处的,实际上可以降低伤亡率,战争中也避免了虐待等问题,所以要设定一些rules,比如1942的小说里面提到的那些规则,不过在现实里面很难运用,列举了一些矛盾的情况。然后提出建议,三个规则,一是技术上的规定,二是伦理的规定的植入,要有利于大多数人,三是更多的合作。。
发表于 2012-6-1 23:34:49 | 显示全部楼层
rena真好~占个座
——————————
有点长 但是差不多明白了
2'01
2'09
1'59
3'03
1'59
发表于 2012-6-2 01:34:20 | 显示全部楼层
2:00
Some scientists declared approaching the revival of the mammoth.
2:21
Problems of relive the mammoth, and plan to do it basing on the elephant’s DNA
1:57
The process may take advantage of the tech. of other cases. The intact nuclei maybe unavailable
3:21
The experiment will be risky and expensive
2:04
The tech can be used in conservation species from extinction

12:50
Robert related regulations are required.

越障是最新一期TE的头条啊
发表于 2012-6-2 11:06:12 | 显示全部楼层
谢谢LZ文章~~~

1'40
1'56
1'56
2'13
1'30

8'02
1. intoduction of RE in military use and commercial use, and some examples respectively.
2. three laws mentioned by a fiction-writer and the its impractical application in real world.
3. the possible ways to solve the RE problems.
3
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