美国国家公共电台 NPR How A Cheap Magnet Might Help Detect Malaria

 

AUDIE CORNISH, HOST:

Each year, malaria¹ kills about half a million people around the world. Health officials say a fast, cheap, accurate way to test for malarial² infection would be extremely helpful in combating the disease. As NPR science correspondent Joe Palca reports, some engineers in California say they have invented a device they hope will do just that.

JOE PALCA, BYLINE³: A few years ago, Andrea Armani heard a lecture from officials at the World Health Organization about the need for better tools for detecting the malaria parasite⁴ in people's blood. Armani is a professor of engineering and material science at the University of Southern California. She says the lecture resulted in a kind of epiphany.

ANDREA ARMANI: I lead a research group with a lot of really smart students. And if I directed all their energy in a concerted effort, we could actually change the world.

PALCA: So that's what she decided⁵ to do. Even though she had no experience with malaria, she decided to build a parasite detector⁶. Her graduate student Samantha McBirney was completely on board with a project aimed at changing the world.

SAMANTHA MCBIRNEY: I've never really envisioned myself being the type of engineer who works on developing the iPhone 23 or works on creating new face filters for Snapchat.

PALCA: So McBirney and Armani started working on their detector. McBirney says they had one overarching goal for their device.

MCBIRNEY: Keeping it as stripped and inexpensive and easy to use as possible.

PALCA: The device is basically a box about the size of a toaster oven. Inside are a laser and a magnet. Andrea Armani says it's not a fancy laser.

ARMANI: It has about the same amount of power as a laser pointer.

PALCA: The magnet is small and cheap, too. But the magnet is key because it turns out that the malaria parasite produces tiny magnetic crystals inside the red blood cells it infects. Normal red blood cells don't have these crystals. So Armani says if you shine a laser light through a sample of uninfected blood and then put a magnet next to the sample, nothing happens.

ARMANI: In contrast, if you have a sample of blood that is infected with the malaria parasite and you put a magnet next to it, the amount of light that can go through that sample will change.

PALCA: The magnet pulls the crystals out of the way so more light can shine through. That change tells you whether the parasite is present. She says the device should be able to detect infections even before someone is showing symptoms. A description of the invention appears in the journal ACS Sensors⁷. There is still a lot of work to be done. Armani is testing her device on animals infected with malaria. Then she'll try it out on infected people. That will take a while. But if you want to change the world, you have to start somewhere. Joe Palca, NPR News.

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1 malaria   

n.疟疾

参考例句：

• He had frequent attacks of malaria.他常患疟疾。
• Malaria is a kind of serious malady.疟疾是一种严重的疾病。

2 malarial   

患疟疾的，毒气的

参考例句：

• Malarial poison had sallowed his skin. 疟疾病毒使他皮肤成灰黄色。
• Standing water like this gives malarial mosquitoes the perfect place to breed. 像这样的死水给了传染疟疾的蚊子绝佳的繁殖地点。

3 byline   

n.署名；v.署名

参考例句：

• His byline was absent as well.他的署名也不见了。
• We wish to thank the author of this article which carries no byline.我们要感谢这篇文章的那位没有署名的作者。

4 parasite   

n.寄生虫；寄生菌；食客

参考例句：

• The lazy man was a parasite on his family.那懒汉是家里的寄生虫。
• I don't want to be a parasite.I must earn my own way in life.我不想做寄生虫，我要自己养活自己。

5 decided   

adj.决定了的，坚决的；明显的，明确的

参考例句：

• This gave them a decided advantage over their opponents.这使他们比对手具有明显的优势。
• There is a decided difference between British and Chinese way of greeting.英国人和中国人打招呼的方式有很明显的区别。

6 detector   

n.发觉者，探测器

参考例句：

• The detector is housed in a streamlined cylindrical container.探测器安装在流线型圆柱形容器内。
• Please walk through the metal detector.请走过金属检测器。

7 sensors   

n.传感器，灵敏元件( sensor的名词复数 )

参考例句：

• There were more than 2000 sensors here. 这里装有两千多个灵敏元件。 来自《简明英汉词典》
• Significant changes have been noted where sensors were exposed to trichloride. 当传感器暴露在三氯化物中时，有很大变化。 来自辞典例句