From VOA Learning English, this is the Technology Report.

　　如不能正常播放，點擊此處下載聽力mp3>>

　　Researchers are now using three-dimensional, or 3D printing to create models of the human heart to help heart specialists. The heart doctors can use the models to better help patients before an operation.

　　Surgeons regularly use digital images to explore the heart in close detail. But no two human hearts are alike. This led Matthew Bramlet to create exact heart models from those images. Dr. Bramlet is a pediatric or children's heart expert at the University of Illinois College of Medicine. He says the 3-D models show information he cannot get any other way.

　　3D-printed model adds new dimension to heart surgery, allowing surgeons to see defects that might not be readily apparent in digital images. (James Carlson, Saint Francis Medical Center)
"Even when I will take the MRI and render the images, even a print heart that is sort of spinning on the screen, it's still a 2-D screen. And so what we've done with the printed models, we've pulled it out of the screen so that you can actually hold it in your hand and evaluate the anatomy for the first time in a manner that makes sense and is logical."

　　A 3-D printer uses images from a digital display to create a physical model of a human heart. Matthew Bramlet says doctors can use the model, in his words, "to understand the anatomy for the first time."

　　Pictures from medical tests like CAT scan or MRI are sent to a 3-D printer to create a heart in a plaster or clay form. The printer then constructs the heart, thin layer by thin layer. Dr. Bramlet says the model matches the real heart in every detail. "When we're done with the model and made our decision, we want to be able to go back to the source image and confirm those findings," he says.

　　Dr. Bramlet has built model hearts for different kinds of heart operations. All of the operations were successful. In his first case, digital images showed only one tiny hole in a baby's heart. But, the 3-D printed model showed several defects or problems that the baby was born with. Dr. Bramlet says those defects could not be seen easily in the images. The heart surgeon was able to change the type of surgery for the patient based on the 3-D model. He added that 3-D heart models saves time during heart operations.

　　Kathy Magliato is a cardiac surgeon at Saint John's Health Center in Los Angeles. She welcomes the new technology. She says it could help her make better decisions before she operates on the hearts of her patients.

　　"The fact that I can then take this very complicated structure, which has endless possibilities of what it could look like anatomically when I open the body, and you give it to me before the operation and I can hold it in my hand and plan an operation around what I'm seeing, touching and feeling. That to me is what can potentially change the game in an operation and save lives."

　　Matthew Bramlet continues to research the technology. He is working with the National Institutes of Health to build a 3-D library that includes heart models and images that others can use.

　　I'm Jonathan Evans.

　　2015年英語四級聽力練習：美國之音慢速VOA匯總

　　聽力技巧：英語四級十大聽力場景詞匯｜應避免的四個壞習慣｜提分五大原則

　　網校課程：為了幫助考生2015年全面的復習備考，順利通過考級，233網校開設有英語四級考試VIPVIP班、精講班、真題解析班、押題班，老師課程，針對考試不同需要，有側重點、分階段的對學員進行輔導。有效結合歷年考試特點，預測考試方向，解密新題型，講解答題思路，傳授應試技巧。

班級	課程	點擊聽課	馬上報名
VIPVIP班 零基礎提分 不過免費重學	VIP班（精講班+真題解析班+模考押題班）
精講班 零基礎精講 全面鞏固	精講班（包括聽力、寫作、閱讀、翻譯、詞匯）
真題解析班 考點難點 全面解析	英語四級真題解析班
押題班 全真模考 考題預測	英語四級模考押題班