Delivering life-saving drugs directly to the brain in a safe and effective way is a challenge for medical providers. One key reason: the blood-brain barrier, which protects the brain from tissue-specific drug delivery. Methods such as an injection or a pill aren’t as precise or immediate as doctors might prefer, and ensuring delivery right to the brain often requires invasive, risky techniques.
A team of engineers from Washington University in St. Louis has developed a new nano-particle generation-delivery method that could someday vastly improve drug delivery to the brain, making it as simple as a sniff.
“This would be a nano-particle nasal spray, and the delivery system could allow medicine to reach the brain within 30 minutes to one hour,” said Ramesh Raliya, research scientist at the School of Engineering & Applied Science.
“The blood-brain barrier protects the brain from foreign substances in the blood that may injure the brain,” Raliya said. “ But when we need to deliver something there, getting through that barrier is difficult and invasive. Our non-invasive technique can deliver drugs via nano-particles, so there’s less risk and better response times.”
The novel approach is based on aerosol science and engineering principles that allow the generation of mono-disperse nano-particles, which can deposit on upper regions of the nasal cavity via spread. The nano-particles were tagged with markers, allowing the researchers to track their movement.
Next, researchers exposed locusts’ antenna to the aerosol, and observed the nano-particles travel from the antennas up through the olfactory nerve, which is used to sense the smell. Due to their tiny size, the nano-particles passed through the brain-blood barrier, reaching the brain and spreading all over it in a matter of minutes.
The team tested the concept in locusts because the blood-brain barriers in the insects and humans have similarities. “The shortest and possibly the easiest path to the brain is through your nose,” said Barani Raman, associate professor of biomedical engineering. “Your nose, the olfactory bulb and then olfactory cortex: two steps and you’ve reached the cortex.”
To determine whether or not the foreign nano-particles disrupted normal brain function, Saha examined the physiology response of olfactory neurons in the locusts before and after the nano-particle delivery and found no noticeable change in the electro-physiological responses was detected.
This is only a beginning of a set of studies that can be performed to make nano-particle-based drug delivery approaches more principled, Raman said. The next phase of research involves fusing the gold nano-particles with various medicines, and using ultrasound to target a more precise dose to specific areas of the brain, which would be especially beneficial in brain-tumor cases.
1. What is the passage mainly about?| A．A novel method of drug delivery. | B．A challenge facing medical staff. |
| C．A new medicine treating brain disease. | D．A technique to improve doctor’s ability. |
| A．Doctors prefer using methods like an injection to treat diseases. |
| B．Locusts were tagged with markers to track their movement. |
| C．The blood-brain barrier lowers the effectiveness of a pill. |
| D．The medicine could reach the brain within half an hour. |
| A．human and locusts have similar structures that protect brain from foreign substances |
| B．the delivery process consists of the olfactory bulb and the olfactory cortex |
| C．locusts have changeable electrophysiological responses to nanoparticles |
| D．the shortest and possibly the safest path to the brain is through human’s noses |
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【推荐1】Telemedicine is the name for when doctors give advice to patients by telephone or the Internet, or when health care providers in rural areas connect with specialists in big cities.
Telemedicine has existed for a long time, but the rise of smart phones, tablets and webcam-equipped computers is raising telemedicine to new levels. Some health care systems in the United States now offer Virtual Urgent Care, patients see a doctor by video chat without having to leave home.
Diana Rae is a nurse educator in the western state of Washington. She recently showed how Virtual Urgent Care works. She used an iPad tablet and skype — the video chat service.
Doctor Green has the patient describe her symptoms, then the doctor performs a physical exam by demonstrating what he wants her to do. Doctor Green decides that the problem is a silence infection. For medicine, he prescribes an antibiotic. He says about 3 out of 4 patients have health problems that can be treated like this —through Virtual Urgent Care, that means a video chat could replace a visit to the doctor's office.
The Franciscan Health System is based in Tacoma, Washington. Franciscan charges $35 for this kind of virtual house call, that is much less than the cost of going to an emergency room, a doctor's office or an urgent care clinic.
After trying the video conference, Diana Rae says, “I would've paid twice that for the convenience of getting taken care of without having to sit in a waiting room, wait, and get exposed to everyone else's germs.”
Franciscan has a deal with a company called Carena to add virtual urgent care by Skype or phone. Carena is one of several companies doing this kind of work around the country. But a company official says state rules have not kept progress with developments in telemedicine. The workers who provide virtual urgent care must be separately licensed in each state where the company does business. For now, that means Carena doctors can treat patients in Washington state and California for example, but not in neighboring Oregon or Idaho.
1. The second paragraph is mainly used to show ________.| A．why telemedicine becomes popular | B．the advantages of telemedicine |
| C．what telemedicine is | D．many factors contribute to telemedicine |
| A．through his observation of the patient | B．through a careful examination |
| C．by prescribing an antibiotic | D．by knowing what he wants her to do |
| A．are tough to deal with | B．can be treated through a video chat |
| C．should result from work pressure | D．nearly cost little to recover |
| A．he finds it convenient to see a doctor by using a video chat |
| B．he sings high praise for this kind of treatment form |
| C．he must be tired of waiting too long in the hospital |
| D．it should be very unhealthy while staying in hospital |
【推荐2】According to a recent poll by the Kaiser Family Foundation’s Vaccine Monitor, nearly a quarter of parents surveyed in the US would not allow their teenagers to be vaccinated.
To help her peers get rid of the embarrassing situation, Kelly Danielpour, 18, from the US, runs VaxTeen, a website that aims to answer questions from teenagers seeking advice about vaccines and what rights they have to make decisions about their health.
With her father as a doctor, Danielpour started volunteering in hospitals in middle school and learned a lot about medicines. Such experiences have made her realize that vaccinations are a good way to keep teenagers from developing health issues they may not be able to get care for later on.
But as she read her peers’ posts on Reddit, a social media platform, she was shocked to find that many of her peers are disapproved to get vaccines. This trend has been more obvious during the pandemic (大流行).
“I found hundreds of posts on Reddit,” the 18-year-old told NBC News. “Every few days, I could still find at least one new post.”
To help them, the first step, she said, is providing the teenagers with information and resources about vaccines so they could get rid of parents’ misinformation. But if that didn’t work, she would get the teenagers information about their healthcare rights.
But that was not easy. Danielpour told Time magazine that every state has different laws on the choices minors can make regarding their own healthcare.
She studied state laws and bookmarked countless pages from the US Centers for Disease Control and Prevention, Healthline website reported. “I did not put anything on the website that I didn’t think would hold up,” Danielpour explained.
The effort paid off. With the help of VaxTeen, more young Americans have been vaccinated.
In fact, she plans to continue encouraging teenagers to place their own medical choices in their hands for years to come. And she advocates for a medical system that provides equal access to healthcare for all.
“This is what I’m passionate about. This is what I do,” she told Healthline.
1. What is the purpose of VaxTeen?| A．To offer legal support to teenagers. |
| B．To persuade teenagers to get vaccinated. |
| C．To give teenagers advice about communicating with parents. |
| D．To provide teenagers with accurate information regarding vaccines. |
| A．Health issues teenagers cannot get care for. |
| B．Her peers’ lack of knowledge about medicine. |
| C．People’s complaints about vaccines on social media. |
| D．The number of teenagers not allowed to get vaccinated. |
| A．It’s hard to collect reliable information about it. |
| B．It’s illegal to post information on laws on unofficial websites. |
| C．Laws on minors’ healthcare decision rights vary in each state. |
| D．Some states have no regulations about minors’ healthcare choices. |
| A．Brave and independent. | B．Thoughtful and cautious. |
| C．Warm-hearted and devoted. | D．Optimistic and knowledgeable. |
【推荐3】Late last year, a French company called Carmat received approval in Europe for its total artificial heart. It’s exactly what it sounds like; a heart made of synthetic and biological materials intended for implantation into people who need heart transplants. Now, just half a year later, the first US patient has received one of the Carmat artificial hearts (CAH).
The transplant took place last week in a 39-year-old man at Duke University Hospital in North Carolina. The man didn’t go to the hospital expecting to have a heart transplant, but it ended up saving his life.
After experiencing unexpected heart failure, he was diagnosed with advanced coronary artery disease and went in for bypass surgery.
When his condition quickly worsened, his medical team realized bypass surgery wasn’t going to do it, but by that point a traditional heart transplant had become too risky. The patient was in the right place, because not just any transplant center could have implanted an artificial heart.
The device weighs 900 grams, or just under 2 pounds (about three times the weight of the average human heart). The external setup is a bit heavier; recipients will have to carry about nine pounds of equipment, including a controller, a bag of actuator fluid, and two battery packs. In the case of the Duke patient, his artificial heart will stay remotely connected to the hospital’s system so that his doctors can monitor it and be sure it’s functioning as it should.
Just days after the US transplant, a similar transplant took place in Naples, Italy, marking Carmat’s first commercial sale of the heart (the difference being that this patient’s transplant was planned, not done as part of a trial).
1. What did the 39-year-old patient go to hospital expecting to have?| A．A heart failure. | B．A heart transplant. | C．A physical exam. | D．A bypass surgery. |
| A．Because that hospital had something to save his life. |
| B．Because there were the best doctors in that hospital. |
| C．Because he knew his medical team well enough. |
| D．Because he wanted an artificial heart. |
| A．Doctors. | B．Patients. | C．Researchers. | D．Nurses. |
| A．CAH Transplanted into First US Patient | B．Carmat Received Approval in Europe |
| C．First Commercial Sale of CAH | D．Man Saved by CAH |
【推荐1】Three paralysed (瘫痪的) men, who were told they would spend the rest of their lives in a wheelchair, are able to walk again, thanks to an electrical device, which was placed around the men’s spines (脊柱) and boosted signals from their brains to their legs.
The first patient to be treated was 30-year-old Swiss man David M’zee, who suffered a severe spinal injury several years ago in a sporting accident. David’s doctor said he would never walk again. However, thanks to the electrical device developed by a team at a public research university in Lausanne, Switzerland, he agreed to take part in a trial led by Dr. Courtine at the university.
“I came with my daughter, Charlotte, who was one month old at the time. As we approached David, he looked her in the eye and said, ‘I will walk before you,’” Dr Courtine recalls. “When Charlotte took her first step she was 14 months old, by which time David was walking by Lake Geneva. He said to her, ‘I have beaten you.’”
David can now walk up to eight paces when the device is switched off and this is the first time that this has been recorded in a chronic (慢性的) spinal injury. However, out of the lab, in the real world, it is hard for David to walk more than a few paces. The signals from the device soon become uncomfortable and so can’t be used all the time. The system is also expensive and not reliable enough to be used out of the laboratory for day-to-day use, so it’s far from a cure.
David is the first of three patients who have benefited from the first wave of the treatment. Two other men have also managed to walk again, to various degrees.
The researchers plan to begin larger trials in Europe and the US in the next few years. If these go well, the researchers are confident the system could become more widely available.
1. How does the electrical device help the paralysed walk again?| A．By straightening the spines. | B．By making the brains recover. |
| C．By signaling the legs to move. | D．By making use of a wheelchair. |
| A．To point out David’s weakness. | B．To explain David’s failure to walk. |
| C．To show the speed of David’s recovery. | D．To prove his daughter’s athletic ability. |
| A．It is hard for typical patients to operate. | B．It is unreliable when used out of the lab. |
| C．It always makes patients uncomfortable. | D．It sometimes sends wrong signals to legs. |
| A．The device can cure paralysis. | B．The device has been widely used. |
| C．The device will be tested globally. | D．The device has a potential market. |
【推荐2】Ren Yamin, an entrepreneur who has been deaf since birth, is using technology to make communication for the hearing impaired easier than ever before through the smart glasses — using artificial intelligence and cloud technology to translate voice into text and project it onto lenses.
The idea for the glasses first came to Ren while he was studying at the University of California, Los Angeles in 2005. However, it was not until after his studies that he could begin bringing his idea to life. While working at a tech company called Integrine, Ren learned a great deal about cloud computing and AT technology. Upon leaving the company and establishing Seeing Voice, Ren launched a cloud platform based on AI and deep learning technologies in 2018 called 40DADOW.
With money coming in from angel investors, Ren said the next stage for his company would be raw material purchase and expansion. A classmate from the University of Science and Technology of China, Zhou Hui, who works as a vice-president at a Fortune 500 company, has provided the parts to make the glasses.
At a recent event held in Toronto, Canada, all 100 of Ren’s prototype glasses sold out. “What I need is not wealth, but to help Chinese who can barely hear,” Ren said, who achieved more success after selling up his company Seeing Voice in the Shanxi Transition and Comprehensive Reform Demonstration Zone in Taiyuan, capital of the province. The company began selling the smart glasses last June, and according to its development plan, production bases covering 5. 33 hectares will be put into operation by the end of 2021.
In the next five years, Seeing-Voice will provide 500 jobs and is projected to generate $ 2. 86 million in tax revenue after 2023, local media reported.
1. What can we learn about Ren from the passage?| A．A sudden accident resulted in Ren’s deafness. |
| B．Ren put his idea into use: when he was at university. |
| C．Ren got down to developing the glasses the moment he resigned. |
| D．Ren had a good command of AI knowledge when studying at university. |
| A．Only at the end of 2021 can the smart glasses be purchased on the market. |
| B．Ren makes the smart glasses totally on his own. |
| C．The purpose of the entrepreneur is to achieve more success by making profit. |
| D．The future application of the smart glasses is promising. |
| A．Ren Yamin — an entrepreneur developed Seeing Voice. |
| B．Smart glasses — Ren’s remarkable invention making voices “heard”. |
| C．40 DADOW — a cloud platform based on AI. |
| D．Seeing Voice — a successful company earned lots of money. |
| A．A culture column. | B．A fictional story. |
| C．A news report. | D．A fashion magazine. |
【推荐3】Sophia Joffe is a Toronto-area high school student at Country Day School who created eLearn. fyi ： an online database compiled （编译）of more than 300 online learning tools. Students are able to access her website to create an online learning profile where they can manage their studies in an approach.
The Grade 12 student used her own experience shifting from a classroom setting to an online platform as inspiration for her program.
“It was really difficult and it was really stressful knowing that right after the outbreak of the COVID-19 we jumped into a totally new online learning system --- it was quite different from an in-class instruction," said Joffe in an interview with CTV's Your Morning on Friday.
She expected that there would be added resources to help students cope as they shifted to an online learning environment9 but her expectations fell short. Not only were there few available, but resources lacked quality, she said.
Like many students, Joffe is concerned the COVID-19 pandemic has caused learning loss for many students. Her goal isn't only to reduce the stress the pandemic has put on students, but remove learning loss altogether.
As was first reported in the New York Times, Joffe invested $ 19 — the cost of hosting a website -- and created eLearn. fyi. By October, Joffe's online traffic had 500 unique visitors from more than 40 countries. The program categorizes grades from Kindergarten to Grade 12, and then breaks subjects down, making it easier for students to digest classroom material in a simple way. Joffe's website clearly organizes students' classes and takes them to simple apps and websites that help guide them through any given subject.
Joffe hopes the Canadian government will one day work in partnership with tech companies to modernize the learning experience and the platforms like Netflix could pose an opportunity where students can stream classes at their own pace while having their entire education at their fingertips.
1. What did Sophia Joffe initially think of online learning?| A．It was less different from classroom learning. |
| B．It really made her feel more or less stressed. |
| C．It was an effective way to fight the COVID-19. |
| D．It provided a good opportunity to create eLearn. fyi. |
| A．Not getting adequate and qualified resources. |
| B．Not knowing how to obtain study materials. |
| C．Having no experience on running a website. |
| D．Finding it a tough job to host a website. |
| A．To gain some income by investing a small sum. |
| B．To get her online database far more perfect. |
| C．To collect some useful learning resources. |
| D．To give a hand to those who are learning online. |
| A．The eLearn. fyi has brought Joffe a big income. |
| B．Joffe has benefited students at home and abroad. |
| C．Joffe also sells some learning apps to students. |
| D．The eLearn. fyi creates a similar classroom environment. |
【推荐1】Although there are fillers（滤镀）which can change digital photographs to make them similar to a painting, obvious differences still exist.
A brand-new painting Al has been made public recently. Much like the pupils of the old masters, the new Al studies the work of great painters like Vermeer and Van Gogh and learns to reproduce their works.
The Al, named "paintBot", is the creation of a team of researchers from the University of Maryland, the Bytedance Al Lab and Adobe Research.
PaintBot can not only reproduce the work of different artists but create new works based on photographs in the chosen painter's characteristic style.
To train the Alto imitate（模 仿）a given artist's technique, the researchers would present it with between 3 and 10 reference paintings. With each reference painting it studies, the Al gradually learns to recognize the various characteristics of the given artist's technique, including the stroke（笔画）color, position and size—along with the order in which each brushstroke should be made.
PaintBot uses a technique known as reinforcement learning（强化学习）.During the learning process, the Al would practice reproducing reference paintings, which it would then compare with the original work to see how similar the two were and if it was improving its imitation of the artist's style. It takes around six hours for the Al to learn to imitate a given painter.
Once the Al has mastered a particular artist's technique, the researchers could present it with a new image to reproduce in the same style. The Al then uses what it has learnt to produce a new painting, putting down each brushstroke one at a time.
After being trained in a given style, PaintBot takes only around five minutes to produce each of its digital masterpieces.
The way that PaintBot's compositions are built up from thousands of individual brushstrokes makes the AI's works more realistic than those online filters.
1. What does the author say about filters used to change digital photos?| A．They do amazing work. | B．They are out of date. |
| C．They have different uses. | D．They are not good enough. |
| A．Learn the artist's techniques. |
| B．Recognize the value of the painting. |
| C．Compare the painting with other works. |
| D．Understand the artist's family background. |
| A．It follows the given style. | B．It learns from the researchers. |
| C．It just imitates the reference paintings. | D．It mixes techniques of different artists. |
| A．Popular. | B．Valuable. | C．Advanced. | D．Lifelike. |
【推荐2】The mission of the National Park Service is to preserve and protect the natural and cultural resources “for the enjoyment, education, and inspiration of this and future generations". Want to help them achieve their mission? Here’s how:
Donate: The national parks are always short on finds (资金). You can donate items to the park bookstore, support a particular program at your favorite national park, or send funds to the National Park Foundation.
Volunteer: If you can’t donate money, consider donating your time. National park service volunteers help build paths, answer visitors’ questions and maintain (维修) buildings. Check out its site to find out more ways you can volunteer in your favorite national park.
Share scientific skills: If you have a background in science, the NPS might be able to use your skills at one of its Research Learning Centers. From collecting and analyzing samples to maintaining equipment and databases, there’s plenty to do to help preserve and protect the natural and cultural resources of our national parks.
Create art: Many national parks have artist-in-residence programs that give artists an opportunity to close to their favorite inspirational settings. You can stay at a remote cabin in Denali National Park or get an in-depth look at the history at Herbert Hoover National Historic Site. The art you create can help inspire future generations to work for the national parks.
Go visit: There’s no better way to show your favorite national park some love than going there to see it. Bring a friend and take in some history and culture. It will remind you why our national parks are really “America’s Best Idea”. Oh, while you’re there, be sure to thank the park workers for all they do to support our national parks.
1. What can volunteers do to help the NPS achieve their mission?| A．Ask visitors some questions. |
| B．Set up a particular program. |
| C．Advertise their works of art. |
| D．Look after park constructions. |
| A．Good scientific skills. |
| B．Great appreciation of the arts. |
| C．A good educational background. |
| D．Much knowledge of history and culture. |
| A．To have a good time. |
| B．To make more friends. |
| C．To help the park workers. |
| D．To show your care for them. |
Here are four of the eight most amazing Chinese food cities I’ve come across so far. The list is in no particular order.
1. Chengdu, Sichuan Province
Crowned as Asia’s first UNESCO City of Gastronomy(美食学) in 2010, Chengdu is best-known for its fiery hot pot and spicy dishes, which are characterized by the use of Sichuan pepper and are usually layered with salty, sour and sweet flavors. There are also dishes that aren’t spicy at all, such as beer-braised duck.
Hot pot is as ubiquitous in the city as the smell of chili. At Zigong Delicious Hotpot, the house specialty(招牌菜) tiaoshui wa is a cauldron(大锅) of fiery chili(辣椒) to which vegetables, noodles or other meats can be added.
For a real taste of Sichuan’s signature（招牌）pepper, hua jiao, spend a morning at the Chengdu Spice Market where the locals sell and buy it by the sack.
2. Lanzhou, Gansu Province
Synonymous in the minds of food-lovers with hand-pulled beef noodles, Lanzhou also has one of the liveliest street food night markets in China.
Just west of the city center, the buzzing Zhengning Road bazaar（集市）houses more than 100 street food stalls. Available is a broad selection of hot and cold dishes with emphasis on local Hui cuisine.
No trip to Lanzhou is complete without feasting on noodles at Wumule Penhui, the 2012 winners of Lanzhou’s annual pulled noodle competition. The halal restaurant makes noodles spicy enough to satisfy even the most hardened heat-seekers.
3. Guangzhou, Guangdong Province
The birthplace of Cantonese food, Guangzhou is thought by many as the best place to eat in China. The city of 12 million has a passionate food culture, with equal excitement reserved for the opening of a hole-in-the-wall congee joint（粥店）and a high-end restaurant.
The local cuisine is characterized by fresh clean flavors（口味）, seafood, barbecued meats and the wonderful tradition of yum cha, which is tea drinking accompanied by dumplings and small dishes.
Congee is the way locals love to start their day, and one of the most popular vendors is Ru Xuan Sha Guo Zhou. Here, one can get a bowl of signature seafood congee any hour of the day.
Roast meats are Bing Sheng’s most popular order—their roast goose is marinated（腌制）with five-spice, boiled, air-dried, then roasted by a flame oven to give a crisp skin.
For something more home style and removed from the madness of downtown, head to Ji Cun for steamed chicken and simple farmer-style dishes.
4. Shaoxing, Zhejiang Province
This ancient canal city is home to huangjiu, an amber-colored rice wine that’s important in Chinese cooking.
Open since 1894, the dining chain is known by almost every Chinese for its appearance in early 20th century novels by Chinese literati Lu Xun.
Xianheng’s delicacies（佳肴）include crispy-skinned chicken, smoked red dates in rice wine, beans flavored with fennel(茴香), and crispy bream in rice wine.
Fried fermented（发酵的）tofu is also a local specialty, which is available all over town at small street stalls including one just outside Xianheng.
1. The writer’s purpose of the passage is to ____________.
| A．express her preference for fiery hot pot |
| B．tell readers how to comment on amazing Chinese food cities |
| C．talk the readers into enjoying the signature food such as hand-pulled noodles |
| D．share her story and impression on Chinese cuisines and spicy dishes in Chengdu. |
| A．charming and attractive |
| B．common and popular |
| C．smelly and disgusting |
| D．fiery and spicy |
| A．Chengdu, Lanzhou | B．Lanzhou, Guangzhou |
| C．Guangzhou, Shaoxing | D．Shaoxing, Chengdu |
