Quicker and faster 3-D printers have allowed not just amazing objects to be created, but have started to affect how doctors treat patients.

    We've put together a list of some of the most amazingmedical break throughs made possible with 3-D printing.

Life-Saving Airway

    In 2013, doctors created a new airway for kaiba Gionfriddo, aboy born with an airway that kept collapsing (萎陷). To save his life doctors printed tiny tubes to join together in different shapes and sizes until one finally worked for Kaiba. It was placed in Kaiba's bronchus (支气管) so that it no longer collapsed. Even more remarkably, once the plant was placed it couldstay there. It's designed to eventually be absorbed into the body.

New “Bionic” Hands

    One of the most remarkable ways 3-D printing is now being used is as a way to create prosthetics (假肢). A boy born without an arm named Alex was able to get a new“bionic”hand thanks to it. Last year a college student spent 8 weeks coming up with a special prosthetic design that only cost a few hundred dollars in materials. He said he wanted to create a prosthetic far cheaper than other choices that can run tens of thousands of dollars.

A practice Heart

    In Seattle, doctors have been able to use 3-D printing technology to“practice”risky operations so that they will face fewer surprises in the operating room. Kami Sutton was born with her heart“in the wrong place”. For a recent operation her doctor was able to take many scans of Sutton's heart and print out a model. “Kami's heart is truly one-of-a-kind,”Dr. Stephan Seslar, a heart disease specialist said. “Operating on her without understanding the structure of her heart better could be very dangerous.”

A New Skull

    A U.K. man was able to have part of his skull rebuilt thanks toa 3-D printer. Stephen Power broke his cheek bones in a crash. To help Powerh is doctors instead created 3-D bones all carefully printed in the shape of his face. “This is really the first time we've taken it to this stage, where everything has been planned and modeled in advance — and worked sweetly,”said Adrian Sugar, a doctor.

    Your kids are amazing especially compared with everybody else's (who seem to cry all the time). How do you show your love for your kids this holiday season? With toys that are smooth and colorful, interactive and exciting. And with ones that have educational value because you are the boss.

1). FLAX ART HOSPITAL PUZZLE AND PLAY SET

    Here is a toy that doesn't need power and the kids have to put it together themselves. This 50-piece puzzle set that can make your children active is made of soft-edged hardwood and make a complete hospital, with an X ray room. It also includes eight patients, a car and a driver. $ 135; flaxart.com.

2). TINY LOVE ACTIVITY BALL

    Sure, it's cool, but this colorful baby toy also develops problem solving and motor skills. It has a head and legs, a magnetic(磁性的) hand and a tail. Suitable for little ones from 6 to 36 months. $19.95; tinylove.com.

3). ROBOSAPIEN

    This small, remote control robot is really powerful. It performs 67 preprogrammed functions(功能), including throwing, kicking, picking up and dancing. You can even program your own function ——which, sadly, does not include doing windows. $99;  robosapienonline.com.

4). MINI PEDAL（脚踏板的）CAR

    Want a Mini Cooper but can't fit the family inside? Get one for the kids. They can jump into this Mini car, which comes in hot orange with a single adjustable(可调的) seat, and ride away. For ages 3 to 5. $189; miniusa.com (click on "gear up," then "Mini motoring gear").

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    Australian cities can keep their native wildlife — but only if they can kick their habit of urban sprawl (扩展). That's the finding of a new study by leading Australian environmental researchers Jessica Sushinsky, Professor Hugh Possingham and Dr. Richard Fuller of The University of Queensland.

    “While urban development usually reduces the number of birds in a city, building more compact (紧凑的) cities and avoiding urban sprawl can slow these reductions greatly,” says lead author Jessica Sushinsky. “Compact housing development leaves birds' homes untouched, leading to fewer losses of birds.”

    The researchers surveyed native and wild birds in Brisbane's urban areas, including living and industrial areas, public parks and gardens, major roadways and airports. They then used statistical modeling to find out what will happen to the birds as the city grows. The first setting was compact growth — where multiple homes are built on land that previously had only one house. The second setting was sprawling growth — a familiar pattern where homes are built here and there beyond the city's current boundaries.

    The team's forecasts showed that a much greater diversity of species was lost over 20 years in the sprawling setting compared to the more compact setting. “Urban sprawl resulted in the disappearance of many urban-sensitive birds — birds that only live in areas where there is native vegetation (植被), such as parklands and woodlands,” Ms. Sushinsky says.

    “On the other hand, we found the city with the compact development attracted more birds because it kept more of its parks and green areas.”

    Now the Queensland Government has adopted the more compact urban growth strategy, which, Dr. Richard Fuller says, is good news for Australia's native birds. These birds are environmental specialists — they need a particular environment to do well. “While compact development means smaller backyards, it can also make our entire cities more biodiverse,” according to Dr. Fuller. “The study shows that we should hold on to our green spaces instead of clearing them for sprawling development.”

    This is the first time science has modeled the effects of different urban growth strategies on birds, the researchers say. “Statistical models like these are important because they help us to understand the ecological consequences of a particular decision,” says Dr Fuller.

    Generally speaking, government regulations normally ban anything from smoking in public places to parking in certain zones. But officials in the Brazilian town of Biritiba Mirim, 70km (45miles) east of Sao Paulo, have gone far beyond that. They plan to prohibit residents from dying early because the local cemetery(墓地) has reached full capacity.

    There's no more room to bury the dead, they can't be cremated(火化) and laws forbid a new cemetery. So the mayor has proposed a strange solution: outlaw death. Mayor Roberto Pereira says the bill is meant as a protest against federal regulations that prohibit new or expanded cemeteries in preservation areas. "They have not taken local demands into consideration", he claims.

    A 2003 decree(法令) by Brazil's National Environment Council forbids burial grounds in protected areas. Mr. Pereira wants to build a new cemetery, but the project has been stopped because 98% of Biritiba Mirim is considered as a preservation area.

    Biritiba Mirim, a town of 28,000 inhabitants, not only wants to prohibit residents from passing away. The bill also calls on people to take care of their health in order to avoid death. "I haven't got a job, nor am I healthy. And now they say I can't die. That's ridiculous," Amarido do Prado, an unemployed resident said.

    The city council is expected to vote on the regulation next week. "Of course the bill is laughable, illegal, and will never be approved," said Gilson Soares de Campos, an assistant of the mayor. "But can you think of a better resolution to persuade the government to change the environmental decree that is prohibiting us from building a new cemetery?" The bill states that "offenders will be held responsible for their acts." However, it does not say what the punishment will be.

Half a Day

    I walked alongside my father, holding his right hand. All my clothes were new: the black shoes, the green school uniform, and the red cap. They did not make me happy, however, as this was the day I was to be thrown into school for the first time.

    "Why school?" I asked my father. "What have I done?"

    "I'm not punishing you," he said, laughing. "School's not a punishment. It's a place that makes useful men out of boys. Don't you want to be useful like your brothers?"

    I was not convinced. I did not believe there was really any good to be had in tearing me away from my home and throwing me into the huge, high-walled building.

    When we arrived at the gate we could see the courtyard, vast and full of boys and girls. "Go in by you," said my father, "and join them. Put a smile on your face and be a good example to others."

    I hesitated and squeezed his hand firmly, but he gently pushed me from him. "Be a man", he said. "Today you truly begin life. You will find me waiting for you when it's time to leave."

    I took a few steps. Then the faces of the boys and girls came into view. I did not know a single one of them, and none of them knew me. I felt I was a stranger who had lost his way. But then some boys began to glance at me in curiosity, and one of them came over and asked, "Who brought you?"

    "My father," I whispered.

    "My father's dead," he said simply.

    I did not know what to say. The gate was now closed. Some of the children burst into tears. The bell rang. A lady came along and said, "This is your new home. There are mothers and fathers here, too. Everything that is enjoyable and beneficial is here. So dry your tears and face life joyfully."

    Well, it seemed that my misgivings had had no basis. From the first moments I made many friends. I had never imagined school would have this rich variety of experiences.

Grizzly bears,which may grow to about 2.5 m long and weigh over 400 kg,occupy a conflicted corner of the American psyche—we revere(敬畏) them even as they give us frightening dreams.Ask the tourists from around the world that flood into Yellowstone National Park what they most hope to see,and their answer is often the same:a grizzly bear.

"Grizzly bears are re-occupying large areas of their former range,"says bear biologist Chris Servheen.As grizzly bears expand their range into places where they haven't been seen in a century or more,they're increasingly being sighted by humans.

The western half of the U.S.was full of grizzlies when Europeans came,with a rough number of 50,000 or more living alongside Native Americans.By the early 1970s,after centuries of cruel and continuous hunting by settlers,600 to 800 grizzlies remained on a mere 2 percent of their former range in the Northern Rockies.In 1975,grizzlies were listed under the Endangered Species Act.

Today,there are about 2,000 or more grizzly bears in the U.S.Their recovery has been so successful that the U.S.Fish and Wildlife Service has twice attempted to de-list grizzlies,which would loosen legal protections and allow them to be hunted.Both efforts were overturned due to lawsuits from conservation groups.For now,grizzlies remain listed.

Obviously,if precautions(预防) aren't taken,grizzlies can become troublesome,sometimes killing farm animals or walking through yards in search of food.If people remove food and attractants from their yards and campsites,grizzlies will typically pass by without trouble.Putting electric fencing around chicken houses and other farm animal quarters is also highly effective at getting grizzlies away."Our hope is to have a clean,attractant-free place where bears can pass through without learning bad habits,"says James Jonkel,longtime biologist who manages bears in and around Missoula.