“Jewel wings fly around like little helicopters until they see preys (猎物), usually smaller flying insects,” said Bellido, a biologist at the University of Minnesota. “Then they dash at their meals in a burst of speed.”
You might mistake jewel wings for their cousins, dragonflies. New research shows that these two insects share something more significant than their appearance, however. In a paper published in Current Biology, Dr. Bellido and the dragonfly colleagues reveal that the neural (神经的) systems behind jewel wings’ vision are shared with dragonflies, with whom they have a common ancestor that lived before dinosaurs. But over the centuries, this brain wiring has adapted itself in different ways in each creature, enabling sharply different hunting strategies.
Jewel wings’ behavior involves attacking what’s directly in front of them, the team found. But recordings made in the lab by Dr. Gonzalez and her colleagues confirmed that dragonflies rise up in a straight line to seize unsuspecting insects from below. Researchers are particularly interested in the neurons (神经元) that send visual information to the wings.
To look closer at the neurons linking vision and flight, the researchers equipped jewel wings with sensors and showed them a video of a moving dot, comparing it with earlier dragonfly research. When a neuron fired, a popping sound filled the researchers’ ears, allowing them to tell exactly which movements-left, right, up, down or some combination-each neuron responded to. Jewel wings best see what’s right in front of them, they found, while dragonflies’ clearest vision is just above them.
The team was interested to find that while jewel wings’ neurons didn’t always respond like those in dragonflies, the number of neurons and organization were similar. That suggests that the system that conveys this information from the eyes to the wing muscles did not evolve recently, but has roots that are millions of years older than the oldest dinosaurs. And that ancient common ancestor likely had already developed remarkable speed in both vision and flight. Then, in the following years, the system has evolved to suit individual insect species.
This shared neural system may be more than 250 million years old, but it is also flexible enough to transform itself to meet the needs of a variety of creatures in different eras and environments, the findings suggest.
1.Jewel wings usually catch their meals ________ them.
A.on the right of B.on the left of
C.straight ahead of D.at the back of
2.What is Paragraph 4 mainly about?
A.What actions jewel wings take to catch preys.
B.How jewel wings ‘neurons respond to vision.
C.When jewel wings start to hunt for their preys.
D.Where researchers did the research into jewel wings.
3.What can we learn about dragonflies and jewel wings from the passage?
A.The two insects possess similar neural systems.
B.Jewel wings’ vision is sharper than dragonflies’.
C.Dragonflies ‘brain wiring is the same with jewel wings’.
D.The oldest dinosaurs react as rapidly as the two insects.
4.What is the main purpose of the passage?
A.To analyse the habits of two similar insects.
B.To tell the difference between dragonflies and jewel wings.
C.To assess the effects of different insects ‘hunting strategies.
D.To present the result of a study on two insects neural systems.
Infectious diseases and associated deaths have reduced, but they remain a significant threat throughout the world. Infectious diseases outbreaks and the fear and panic that accompany them present various economic risks.
First, there are costs to the health system, both public and private, of medical treatment of the infected and of outbreak control. Concern over the spread of a relatively contained outbreak can lead to decreased trade. Travel and tourism to regions affected by outbreaks are also likely to decline. Some long-running outbreaks, such as HIV, prevent foreign direct investment.
The economic risks are large. It is estimated that the expected yearly cost of infectious diseases is at roughly $500 billion. Even when the health impact of an outbreak is relatively limited, its economic consequences can quickly become expanded. Liberia, for example, saw GDP growth decline 8 percentages from 2013 to 2014 during the Ebola outbreak in Africa.
The risk is complex, but policymakers have tools in response.
Investing in improved health care, supply of clean water, and better health systems can reduce the frequency of human contact with viruses. Investment in reliable disease monitoring in both human and animal populations is also critical. Within formal global watch systems, instead of discouraging reporting possible outbreaks, it may be beneficial to develop incentives for reporting suspected cases, as countries may reasonably fear the effects of such reporting on trade, tourism, and other economic outcomes. Informal monitoring systems, social media for example, which collect information from official reports, media reports, online discussions, and eyewitness observations, can also help national health systems and international responders get ahead of the outbreak news during the early stages. Cooperations for monitoring infectious diseases readiness at the national level provide information national governments can use to react timely to their outbreaks.
There is a significant market failure when it comes to vaccines (疫苗) against individual low-probability viruses that collectively are likely to cause panic. Given the low probability that any single vaccine of this type will be needed, high Research and Development (R&D) costs, and delayed returns, medical companies hesitate to invest in their development. However, responsible international corporations such as CFPI can overcome this market failure. Its goals include advancing candidate vaccines against specific low-probability, high-severity viruses through proof of concept to enable rapid clinical testing in the event of outbreaks. It also aims to fund development of institutional and technical platforms to speed R&D in response to outbreaks for which there are no vaccines.
Undoubtedly, humans and infectious viruses will coexist. However, we can take effective measures to manage the risk of the diseases. Joint action now at the local, national, and multinational levels can go a long way toward protecting our collective well-being in the future.
1.What does the underlined word ''incentives'' in Paragraph 5 probably mean?
A.Habits. B.Opinions.
C.Arguments. D.Rewards.
2.CFPI is a special company which
A.is able to predict the trend of the market
B.develops vaccines against infectious viruses
C.makes huge profits by selling general medicine
D.employs staff who graduate from famous universities
3.What does the passage imply?
A.More importance should be attached to health care systems.
B.All-level cooperations are required to handle infectious diseases.
C.It will not be long before mankind thoroughly defeats the viruses.
D.Technologies hold the key to the settlement of medical problems.
4.Which of the following would be the best title for the passage?
A.Health Risks and Research of Infectious Diseases
B.Global Cooperation and Spread of Infectious Diseases
C.Economic Impact and Solutions of Infectious Diseases
D.Medical Service and Development of Infectious Diseases
Autumn Peltier is a youth environmentalist who has inspired thousands of students to walk out of class and demand action on climate change.
When Autumn Peltier was just 8 years old, she attended a ceremony at a reservation where she saw a sign warning that the water was poisonous. Growing up on a freshwater island in Wiikwemkoong Unceded Territory in Canada, Peltier says she had never experienced poisonous water. The memory of that sign stayed with her.
Two years later, at the age of 10, Peltier is fighting for water conservation and water rights for everybody. She says she was inspired by her great aunt, Josephine Mandamin, a well-known activist who walked the shores of all five Great Lakes to raise awareness for water conservation.
When she was 12 in 2015, Peltier met Canadian Prime Minister Justin Trudeau, telling him she was unhappy with his policies on debating pipeline projects. Trudeau promised her he would preserve the water. Since 2015, 87 long-term water advisories in Canada have been lifted; 56 water advisories remain.
At middle school, Peltier joined an environmental group at her school and later co-founded the Canadian Youth Water Strike-a Canadian branch of the international movement to conserve water.
Last year, Peltier spoke at the UN about the importance of water conservation and water access, explaining the fundamental role water plays in her culture.
“Many people don’t think water is alive or has a spirit. My people believe this to be true. . . . We believe our water is precious because we are born of water.”
After the speech at the UN, Peltier is joined by a group of teenagers who share similar thoughts. Her friends include Greta Thunberg, a Swedish girl who drew the world attention through the talk at World Economic Forum at Davos, Bruno Rodriguez, an Argentinian boy who joined in the UN Climate Summit, and Mari Copeny, an American girl who is dedicated to the cause of saving water. Peltier and her friends believe that together they can make a big difference.
Undoubtedly, Peltier’s many years of hard work has paid off. She has greatly raised people’s awareness of water conservation and taught people to take specific actions to conserve water.
That’s an impressive list of accomplishments for anyone, let alone a middle schooler.
1.How did Peltier feel about the poisonous water when she was 8?
A.Shocked. B.Interested. C.Excited. D.Bored.
2.Who influenced Peltier to start water conservation?
A.UN officials. B.Trudeau. C.Mandamin. D.Thunberg.
3.What does Peltier expect to do in the future?
A.To make more friends. B.To protect more water.
C.To attend more summits. D.To organize more strikes.
4.What can we learn from Autumn Peltier’s story?
A.World leaders can contribute to success.
B.Environment is Canadians’major concern.
C.Fame comes from attending great summits.
D.Achievements result from continuous effort.
Who can be volunteering?
A Ugandan NGO (Non-Governmental Organization) was formed by members of a rural community in South-west Uganda in 2007. They developed a local school for children aging from 3 to 15 from poor families, and started community based projects that will equip the young villagers with the skills and knowledge to face a safer and brighter future.
The project itself is well integrated into the community and those undertaking volunteering work are always given a warm welcome, especially by the local children who love spending time with volunteers from all ages and backgrounds.
Volunteering at Uganda Lodge is suitable for families, gap year teenagers, seniors etc.
For medical students we can offer you official medical elective course scores with no additional fees charged. Staying at Uganda Lodge could also count for the residential section of the Gold Award and Queens Scout Awards.
What can I do?
You need to speak English. Even if you are not a Teaching English as a Foreign Language (TEFL) teacher (although useful!), you can go into the classrooms and make a meaningful difference. Experienced teachers can take over a whole class if they wish, after consulting with the teacher on content.
We now have over 500 students in the Ruhanga Development School and they are in urgent need of teachers. English conversation is needed for the older children in particular, also showing picture books etc. or simply talking to babies helps inspire their mental and physical growth.
Children at our kindergartens and primary schools do love help from our volunteers to learn new rhymes and songs, talk about pictures in books or get inspirations with craftwork and painting.
Find out more about our programme:
Website: ugandalodge.com
Email: ann@ugandalodge.com
1.What is the main purpose of the passage?
A.To praise volunteers. B.To raise money.
C.To seek help. D.To introduce a school.
2.After the programme, optional course credits can be awarded to
A.medicine-major students B.education-major students
C.IT-major students D.English-major students
3.Who is most wanted at present according to the passage?
A.An American lady who cares about international sports events.
B.A British college student who loves to communicate with kids.
C.An Australian teenager who enjoys reading English books silently.
D.A Canadian white collar manager who does well in performing art.
Last summer, Steller pulled off the freeway on her way to work in Minneapolis. She stopped at a traffic light, where a man was sitting with a sign asking for help. She ________ down her window.
“Hey!” she shouted. “I’m driving around giving ________ haircuts. If I go and grab my ________, do you want one right now?”
The man looked to be in his 60s. He was heavyset, and ________ a few teeth. He laughed, and then paused, “________, I was really hoping to get a haircut.”
“I’ll be right back,” Steller said.
She drove off, went to the salon she owns, and ________ a red chair into her car.
Quickly she ________ back. Then she cut the man’s curly graying hair. The man told her about growing up in Mississippi, about moving to Minnesota to be closer to his adult children, and how he still talks to his mom every day.
After Steller was done, the man looked in a mirror and ________, “I look good!” he said. “I’ll have to remember to put my artificial teeth in next time.”
To date, Steller has given about 30 such haircuts to people around the city. These clients are all living down and out, so she is clearly aware of the ________ of her cleanup job.
In fact, for Steller, it’s more than a haircut. It is not only a gateway to show value and ________, but also to get to know people. She wants to ________ relationships.
Steller knows that a haircut can ________ a life because one changed hers: As a teen, she suffered from a disease called ulcerative colitis, which was so ________ that her hair thinned severely. Seeing this, her mother arranged for Steller’s first professional haircut.
Sitting down and having somebody look at her made Steller feel that she was a ________ and not just an illness, which helped her feel ________ and less alone.
After that, Steller decided to have her own salon so she could help the people ________ the feeling she’d had that day. Not long after finishing hairdressing school in 2009, she began what she now calls her Red Chair Project, ________ out to people on the streets. Steller listens to people’s stories of ________, suffering, and struggle to get back on their feet. She believes even if she can’t ________ their problems, maybe she can help them feel less alone for a moment. The attention ________ works.
And it all began with a belief in simple acts of kindness, such as a free haircut.
1.A.took B.rolled C.knocked D.tore
2.A.quick B.modern C.free D.luxurious
3.A.chair B.table C.knife D.glove
4.A.growing B.showing C.pressing D.missing
5.A.Actually B.Curiously C.Occasionally D.Particularly
6.A.turned B.loaded C.fastened D.restored
7.A.ran B.walked C.cycled D.drove
8.A.recognized B.wept C.smiled D.guessed
9.A.power B.profit C.reward D.technique
10.A.wealth B.pride C.innocence D.respect
11.A.judge B.build C.break D.clarify
12.A.make B.ruin C.change D.extend
13.A.serious B.regular C.natural D.obvious
14.A.student B.pioneer C.advisor D.person
15.A.commented on B.cared about C.laughed at D.convinced of
16.A.feel B.describe C.remark D.transfer
17.A.showing B.reaching C.speaking D.pointing
18.A.anger B.envy C.loss D.shock
19.A.find B.list C.treat D.fix
20.A.rarely B.accurately C.apparently D.secretly
阅读下列短文，根据短文内容填空。在未给提示词的空白处仅填写1个适当的单词，在给出提示词的空白处用括号内所给词的正确形式填空。
As humans, we naturally tend to notice the bad events in life more than the good. It is because we need to keep an eye on the negative ones to keep us far away 1. dangers. If we are aware of threats around us, we are more able to switch on a defense. However, if we 2. (active) turn to focus on the positive, we can feel less stress and enjoy life more from an increasingly optimistic point. To enjoy the life in the present moment, we need to notice 3. is going right, and appreciate it. It doesn't mean that you have to pretend you're happy when you're not. On the contrary, it means that you tend to notice the things that lead to greater 4. (happy) when you have a choice.
