A
(2021·北京模拟)
Alzheimer’s AI
An estimated 5. 7 million people in the U. S. have Alzheimer’s disease—the most common type of dementia(痴呆)-and that number is expected to more than double by 2050. Early diagnosis is crucial for patients to benefit from the few therapies available. But no scans can deliver a conclusive diagnosis while a person is alive; instead doctors have to conduct numerous and complicated clinical and neuropsychological tests. So there is growing interest in developing artificial intelligence to identify Alzheimer’s based on brain imaging.
Researchers at the University of California, San Francisco, have now successfully trained an AI algorithm(算法)to recognize one of the early signs of Alzheimer’s—a reduction in the brain’s glucose(葡萄糖)consumption—in positron emission tomography (PET) imaging.
The algorithm accurately predicted an eventual Alzheimer’s diagnosis in nearly all the test cases, according to the study. In PET imaging, a very small amount of a radioactive compound is injected into the body, producing three-dimensional images of metabolism(新陈代谢), circulation and other cellular activities. PET is well suited for an AI diagnostic tool because Alzheimer’s leads to subtle changes in the brain’s metabolism that begin years before neural(神经的) tissue starts to go downhill, says study co-author Jae Ho Sohn, a radiologist at UCSF. These changes are “very hard for radiologists to pick up, ”he notes.
The algorithm was trained and tested on 2, 100 PET brain images from about 1, 000 people 55 years and older. The images came from a 12-year study that tracked people who would ultimately be diagnosed with Alzheimer’s, as well as those with mild memory declines and healthy control participants. The algorithm was trained on 90 percent of the data and tested on the remaining 10 percent. It was then retested on a second, independent data set from 40 patients monitored for 10 years. The algorithm was highly sensitive and was able to recognize 81 percent of the patients in the first test group and 100 percent in the second who would be diagnosed with Alzheimer’s six years later, on average. The findings were published in February in Radiology.
The algorithm is based on deep learning, a machine-learning technique that uses artificial neural networks programmed to learn from examples. “This is one of the first promising, preliminary(初步的) applications of deep learning to the diagnosis of Alzheimer’s, ” says Christian Salvatore, a physicist at Italy’s National Research Council, who was not involved in the study. “The model performs very well when identifying patients with mild or late diagnoses”, he says, “but catching it in the earliest stages remains one of the most critical open issues in this field. ”
【文章大意】本文主要介绍了利用人工智能诊断老年痴呆症能够较早确诊。
1. People are increasingly interested in using AI to identify Alzheimer’s because .
A. the number of people suffering from dementia is more than doubling
B. diagnostic methods that are both reliable and convenient are in need
C. there are only a limited number of effective therapies for the patients
D. diagnosing Alzheimer’s disease through AI is still an unexplored area
【解析】选B。推理判断题。根据第一段可知, 早期诊断对于患者是至关重要的, 但是, 在一个人还活着的时候, 医生必须进行大量复杂的临床和神经心理学测试。因此, 人们需要既可靠又方便的诊断方法, 所以越来越有兴趣开发人工智能来识别基于大脑成像的老年痴呆症。故选B。
2. What can we learn about PET imaging?
A. It recognizes the worsening of the neural tissue.
B. It reduces the glucose consumption in the brain.
C. It changes the pattern of the brain’s metabolism.
D. It photographs various kinds of cellular activities.
【解析】选D。细节理解题。根据第三段的“In PET imaging, a very small amount of a radioactive compound are injected into the body, producing three-dimensional images of metabolism(新陈代谢), circulation and other cellular activities可知, PET影像拍摄各种细胞活动。故选D。
3. According to Paragraph 4, .
A. 90% of the people in the study were trained on the algorithm
B. the participants in the study consist of people both young and old
C. 81% of the people in the first test group were diagnosed with Alzheimer’s
D. the algorithm managed to recognize all the patients in the second test group
【解析】选D。细节理解题。根据第四段The algorithm was highly sensitive and was able to recognize 81 percent of the patients in the first test group and 100 percent in the second who would be diagnosed with Alzheimer’s six years later可知, 该算法成功地识别了第二试验组的所有患者。故选D。
4. What can be inferred from Paragraph 5?
A. The algorithm serves as a promising treatment of Alzheimer’s.
B. Deep learning has been widely applied in diagnosing Alzheimer’s.
C. To detect Alzheimer’s in its earliest stages calls for more exploration.
D. Whether to use the model to detect Alzheimer’s remains a critical issue.
【解析】选C。推理判断题。根据第五段but catching it in the earliest stages remains one of the most critical open issues in this field. 可知, 要在最早的阶段发现老年痴呆症, 需要更多的探索。故选C。
【知识拓展】长难句分析
The algorithm was highly sensitive and was able to recognize 81 percent of the patients in the first test group and 100 percent in the second who would be diagnosed with Alzheimer’s six years later, on average.
分析:该句是复合句。主句中and连接并列谓语was highly sensitive和was able to recognize, 81 percent of the patients in the first test group and 100 percent in the second是并列宾语, 作recognize的宾语;who引导的是定语从句, 修饰先行词patients。
翻译:该算法非常敏感, 能够识别第一个测试组中81%的患者和第二个测试组中100%的患者, 平均6年后被诊断为“老年痴呆症”。
【加固训练】 阅读理解
If you live in Washington D. C. or Redwood, Calif. , you may have glimpsed a small, boxy robot rolling along a local sidewalk, minding its own business, but attracting the attention of many a curious onlooker.
The robots, which look like electric rice cookers with wheels, were part of a pilot program last year by Starship Technologies focused on delivering meals from local restaurants in dozens of cities around the world.
This week, the company revealed plans to broaden its delivery service beyond food to include packages, a move that made it “the world’s first robot package delivery service”. The package delivery service is only available in some cities in the US.
The wheeled robots have a top speed of 4 mph and can detect barriers from as far as 30 feet away. “The robot can operate through just about anything, ” says Nick Handrick, head of operations for Starship’s D. C. office, “If you have something in the way, it’s able to climb it. ” By giving customers control of when deliveries occur, Starship Technologies is promoting its service as a way to combat package theft.
To sign up for the service, which costs a little more than $10 per month, customers need to download the company’s app. Customers then create a “Starship Delivery Address”, a unique address inside a Starship facility, instead of a home address, where they can have packages sent from places such as Amazon. com.
Once a package is delivered to the Starship address, customers receive a text notice that allows them to schedule a home delivery via robots. The robots are opened by customers with a mobile phone code (代码).
【文章大意】本文为说明文。文章主要讲了在美国的一些城市, 包裹可以由机器人运送了。
1. What do we know about Starship Technologies company?
A. Packages are delivered by its robots all round America.
B. Its robots have taken on package delivery for a long time.
C. It is the first to provide robot package delivery service.
D. Its delivery service is the best of all in the world.
【解析】选C。细节理解题。根据第三段This week, the company revealed plans to broaden its delivery service beyond food to include packages, a move that made it “the world’s first robot package delivery service”. (本周, 该公司公布了将送货服务从食品扩展到包裹的计划, 此举使其成为“世界上第一家送货机器人”。)由此可知星际飞船技术公司是第一家提供机器人包裹递送服务的公司, 故选C。
2. What does the underlined word “combat” in Paragraph 4 probably mean?
A. Delay. B. Prevent.
C. Report. D. Discover.
【解析】选B。词义猜测题。由第四段By giving customers control of when deliveries occur(通过让客户控制何时发货), 可以推断出下文Starship Technologies is promoting its service as a way to combat package theft. 意思是星际飞船技术公司正在提升其服务, 作为一种防止包裹盗窃的方式。combat意思是“防止”。故选B。
3. What can we learn about robot package delivery service?
A. Customers can’t open the robots without a mobile phone code.
B. Starship Delivery Address is the customer’s home address.
C. Customers have to pay a little more than $10 each time.
D. Robots themselves have control over when to deliver packages.
【解析】选A。推理判断题。根据最后一段The robots are opened by customers with a mobile phone code (这些机器人由顾客用手机代码打开), 可知没有手机代码, 顾客无法打开机器人, 故选A。
4. What may be the best title for the passage?
A. Robot Delivery Service Is Taking Off
B. Humans Are Being Replaced by Robots
C. Everything Can Be Done by Robots
D. Packages Can Be Delivered by Robots
【解析】选D。主旨大意题。第三段This week, the company revealed plans to broaden its delivery service beyond food to include packages, a move that made it “the world’s first robot package delivery service”. 是全文的主题句, 结合全文内容, 可知这篇文章主要讲了在美国的一些城市, 包裹可以由机器人运送了。故选D。
【知识拓展】长难句分析
By giving customers control of when deliveries occur, Starship Technologies is promoting its service as a way to combat package theft.
分析:本句为简单句, By giving customers control of when deliveries occur是介词短语作状语, 其中when引导的句子作介词of的宾语从句;to combat package theft作a way的定语。
翻译:通过让顾客控制什么时候投送快递, 星际飞船技术公司正在提升其服务, 作为一种打击包裹盗窃的方式。
