In patients with metabolic(新陈代谢的) diseases, elevated(升高的) fat levels in the blood create stress in muscle cells-a reaction to changes outside the cells that could damage their structure and function. Researchers have discovered that these stressed-out cells could give off a kind of signal.
The signals, known as ceramides(神经酰胺), may have a protective benefit in the short term because they are part of a mechanism(机制) designed to reduce stress in the cells. But in metabolic diseases, which are long-term conditions, the signals can kill the cells, make symptoms severer, and worsen the illness.
Increased fat in the blood has long been known to damage tissues and organs, contributing to the development of cardiovascular(心血管的) and metabolic diseases, including type 2 diabetes(糖尿病). The condition can be caused by obesity(肥胖), rates of which have increased greatly worldwide since 1975. In 2016, there were more than 650 million adults aged 18 and above with obesity.
Rescarch supervisor Lee Roberts said, “Our discovery may form the basis of new approaches to preventing the development of cardiovascular and metabolic diseases, such as diabetes in overweight people with elevated blood fat.”
In the lab, the team copied the blood fat levels observed in humans with metabolic diseases by exposing certain muscle cells to a fatty acid. The cells began to pass on the ceramide signal. When these cells were mixed with others that had not been previously exposed to fat, the researchers found that they communicated with each other, transporting the signal in packages called extracellular vesicles. The experiment was reproduced in human volunteers with metabolic diseases and got comparable results.
Professor Roberts said, “The research gives us a novel perspective on how stress develops in the cells of individuals with obesity, and provides new ways to consider when we’re trying to develop new treatments for metabolic diseases. With obesity becoming an increasingly widespread disease, the burden of associated chronic(慢性的) diseases, such as type 2 diabetes, necessitates new treatments. We hope the results of our research open a new avenue for research to help address this growing concern.”
1. What is special about ceramides?| A．They are released by healthy cells. |
| B．They are harmful to cells in the long term. |
| C．They are designed to reduce the fat levels in the blood. |
| D．They are beneficial to the treatment of metabolic diseases. |
| A．The difficulty of dealing with obesity. |
| B．The consequence of chronic diseases. |
| C．The general health condition of young people. |
| D．The increasing rates of obesity around the world. |
| A．It aimed to find the cause of metabolic diseases. |
| B．It identified a new cell in volunteers with obesity. |
| C．It proved stressed-out cells could affect healthy cells. |
| D．It indicated cells’ communication patterns for the first time. |
| A．How cells respond to the stress from high blood fat. |
| B．How our body distinguishes stressed-out cells from others. |
| C．How muscle cells communicate with each other effectively. |
| D．How our body starts the self-protection system to repair cells. |
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【推荐1】Tansel Ali used to curse his terrible memory. He struggled to remember phone numbers. But now he has won the Australian Memory Championships four times and has represented Australia at the World Memory Championships, where he was able to memorise 80 words in 15 minutes and 41 names and faces in five minutes.
So how did Tansel's memory improve so much? The key, he says, is in encoding information into an image. Tansel also creates images when remembering numbers. That involves a lot of "pre-work", he explains. “I've got images already pre-memorised from 0 to 99. So, for example, 17 is a dog and 71 is a cat, so if I get the number 1771, I'm going to picture a dog chasing a cat.” And it works.
“If you want to strengthen your own recall skills, Tansel suggests reading something incredibly dry and boring, such as a “terms and conditions” page. While doing so, create a story in your mind. If you can make a story out of what you're trying to remember, you car essentially memorise anything.”
Psychologist Sharon Draper says there are other ways to boost your memory, including doing brain challenges such as puzzles, crosswords and Sudoku at least once a day. "Being physically active, avoiding smoking, reducing alcohol intake and aiming for a solid night's sleep can also help protect your memory from going through the sieve", Draper adds. And dietitian Kathryn Hawkins notes that sticking to a well-balanced diet—with plenty of fresh fruit, vegetables and fish high in omega-3 fatty acids—will promote brain health and thus memory.
There's no denying that Tansel now has a great memory. But it's not the only thing to improve since he started training his brain: his confidence and self-esteem have skyrocketed, and his stress levels have fallen dramatically as a result. “The better you become at sharpening your memory”, Tansel has learnt, “the easier life becomes.”
1. Which of the following was adopted by Tansel to improve his memory?| A．Eating a balanced diet. | B．Doing brain challenges. |
| C．Creating a story in his mind | D．Guaranteeing a good night's sleep. |
| A．To share more techniques of living an easy life. |
| B．To introduce more benefits of training our brain. |
| C．To illustrate the importance of having a good memory. |
| D．To show the relationship between confidence and self-esteem. |
| A．The Legend of Tansel | B．The Secret of Tansel |
| C．The Power of Memory. | D．The Improvement of Memory |
【推荐2】A butterfly's wings can have many jobs besides keeping the insect in the air. They may be called on to attract mates, to warn potential enemies to stay away, to do other animals or even to provide disguise（伪装）.
All of these roles, though, depend on their colouration—which is unchanging. This plays into the idea that butterfly wings are dead tissue, like a bird's feathers or a mammal's hair. In fact, that is not true. For example, in some species males' wings harbour special cells that release chemicals which attract females.
Nanfang Yu, a physicist at Columbia University, in New York, has been looking into the matter. One of his interests is the optical（光学的）properties of biological materials. That has led him to study butterfly wings in more detail. And, in cooperation with Naomi Pierce, a butterfly specialist at Harvard University, he has now shown, in a paper published this week in Nature Communications, that butterfly wings are, indeed, very much alive.
Initially, Dr Yu and Dr Pierce wanted to know how the insects keep their body temperatures up without their wings overheating.
Unlike birds and mammals, butterflies do not produce enough internal heat to metabolize（新陈代谢）. Instead, they rely on outside heat sources—usually the sun—to bring their bodies up to speed. But their wings, being thin protein membranes（膜）, have a limited thermal capacity. Those wings can therefore overheat quickly if the insects are exposed to the sunlight too long, or, oppositely, can cool down too rapidly if they are flying through cold air.
In their experiments, the two researchers used a laser（激光）to heat up spots on the wings of dozens of butterfly species. When the temperature of the area under the laser reached 40℃ or so, the insects responded within seconds by doing things that stopped their wings heating up further. These actions included a butterfly turning around to minimize its exposure to the laser, beating its wings or simply walking away.
1. What's Dr Yu's discovery about butterfly wings?| A．They contain dead tissue. |
| B．They are too thin to store heat. |
| C．They have different functions. |
| D．They react quickly to high heat. |
| A．Butterflies metabolize completely with its internal heat. |
| B．Chemicals from butterfly wings help drive away threats. |
| C．The color of butterfly's wings keeps fixed. |
| D．The researchers achieved big in optical properties. |
| A．By providing heat itself. |
| B．By flying through cold air. |
| C．By removing the source of heat. |
| D．By adjusting their heating surface. |
| A．A Research into Butterfly Wings |
| B．The Jobs of Butterfly Wings |
| C．Butterfly Wings: Dead or Alive |
| D．Butterfly Wings Temperature Changes |
【推荐3】Enhance Your Wellbeing in Nature
Nature reduces our anger, fear, and depression and increases our positive mood and psychological wellbeing. Time in nature also brings us out of ourselves and our narrow concerns and connects us to a larger world where we find beauty and interest.
It is clear that it is important to get outside!
We all know the long list of physical, mental, and emotional benefits of exercise. Exercise improves attention in the young and cognitive functioning in the old. It reduces stress and acts as an antidepressant.
| A．If you can get to the country, or a lake, that’s wonderful. |
| B．Exercise is also the key if we want to avoid gaining weight. |
| C．So find somewhere with trees or bushes to go for a walk. |
| D．The beauty of natural surroundings can keep us motivated. |
| E．Thus the environment is connected to our overall wellbeing. |
| F．You should find more energy for your afternoon mental tasks. |
| G．Moreover, exercising outdoors reduces stress even more than exercise indoors. |
【推荐1】What killed King Tut? Historians and scientists have long believed that ancient Egypt’s most famous king was probably murdered. But a recent scientific study claims to have found a different answer to this more than 3,300-year-old mystery. A team of researchers now say that King Tut, the boy ruler, died of complications (并发症) from a broken leg.
Tut’s full name was Tutankhamun. He was just 9 years old when he became the ruler of Egypt. His treasure-filled tomb was discovered almost a century ago. It was filled with royal riches, including a solid-gold coffin, a gold mask, and piles of jewelry.
Unfortunately Tut died at the age of 19. Many experts have thought that Tut was killed by one of his advisers, named Ay, who wanted to be king. But thanks to a major modern science project, it seems Ay is innocent.
Researchers set out to solve the mystery of King Tut’s death by using the tools of science, including DNA tests and electronic scans of his mummy (木乃伊). Scientist Carsten Pusch conducted the tests on Tut for the new study. He thinks a broken leg contributed to the young king’s death.
More than 100 walking sticks were found in King Tut’s tomb. This supports the team’s findings. But how could a person die from a simple broken leg?
Pusch also found DNA evidence in Tut’s body that indicates he had malaria (疟疾), a disease carried by mosquitoes. Malaria severely weakens the immune system.
Pusch and his fellow researchers believe the malaria and the bone disease together caused the king’s fracture (骨折) to become deadly. Finally, the young king was just too weak to recover. So effects of the disease combined with the bad luck of a broken bone — not a jealous adviser — are likely the real causes of King Tut’s death.
1. It has long been believed by historians and scientists that _____.| A．King Tut was the youngest ruler in the world history |
| B．King Tut was the richest ruler in the history of Egypt |
| C．King Tut was murdered by one of his advisers |
| D．King Tut was poisoned by one of his servants |
| A．the king had been dead for 3,300 years |
| B．the king was buried grandly |
| C．the king was born with a bad immune system |
| D．the king’s body was well kept in the tomb |
| A．testing the king’s immune system |
| B．studying the walking sticks found in the tomb |
| C．performing experiments on mosquitoes |
| D．applying DNA tests and electronic scan technology |
| A．a different answer to King Tut’s death |
| B．a famous boy king in ancient Egypt |
| C．a treasure-filled tomb discovered in Egypt |
| D．a team of researchers studying ancient tombs |
【推荐2】What’s brown, slimy(黏滑的) and can move through narrow passages inside the body? It’s probably not what you’re thinking!
Scientists at the Chinese University of Hong Kong have created a magnetic (有磁性的) slime robot! It can carry out tasks like fixing broken circuits (电路) and picking up objects. They also think one day it could be put inside the human body to do things like help find items that have been swallowed by accident.
Li Zhang and his workmates mixed a range of substances together to make the slime which can be controlled by an outside magnetic field. They also added a substance that coats the magnetic parts to make them non-toxic (无毒的) for use in the human body.
The team then tested how well the soft-bodied robot functions in a range of situations, including finding and surrounding a lost battery in a model stomach and moving along while holding onto a piece of wire and also getting through tiny gaps.
There are robots in existence which can successfully find and hold onto objects and others that can go through tight spaces, however there aren’t many that can do both. The robot can also heal (治愈) itself after being cut into pieces.
“You can first pull it to a great extent so it looks like a liquid. Then afterwards, you can roll it like an octopus’ arm to carry something,” Li Zhang said.
“However, before they can use the robot inside a real person’s body, the scientists will first need to come up with a way of knowing where the robot is and how it’s performing,” Pietro Valdastri from the University of Leeds said. It would also need to be tested to make sure the magnetic parts which are toxic on their own aren’t able to separate from the slime. “They need to ensure its safety through future trials, but it’s definitely a sound approach,” Valdastri added.
1. What can be learned about the slime robot?| A．It performs tasks by itself. |
| B．It can repair circuit boards. |
| C．It is harmful to the human body. |
| D．It can find mistakenly-swallowed objects. |
| A．They used it to fix a broken battery. |
| B．They put it into a real medical setting. |
| C．They checked how it recognised toxic substances. |
| D．They let it search for objects in a stomach model. |
| A．It is small and hard. |
| B．It can hold onto objects gently. |
| C．It is able to access hard-to-reach places. |
| D．It can pick up items and move through tight spaces. |
| A．It will need to be tracked. |
| B．It can behave like a liquid. |
| C．It should avoid non-toxic magnetic parts. |
| D．It can heal itself after being broken into pieces. |
【推荐3】2500 years ago, Socrates (苏格拉底) complained that writing would harm students.
Today a different heated debate is ongoing about the dangers of another technology —computers — and the typing people do on them. As primary-school pupils and PhD hopefuls return for a new school year in the northern hemisphere, many will do so with a greater-than-ever reliance on computers to take notes and write papers. Some parents of younger students are frustrated that their children are not just encouraged but required to carry laptops to class. Lot s of teachers complain of uncontrolled distraction in classrooms, with students reading and messaging instead of listening to lectures.
A line of research shows the benefits of an “innovation” prior to computers: hand-writing. Studies have found that writing on paper can improve everything from recalling a random series of words to facilitating a better conceptual grasp of complicated ideas. For learning material by rote, from the shapes of letters to the quirks of English spelling, the benefits of using a pen or pencil lie in how the motor and sensory memory of putting words on paper reinforces that material. The arrangement of squiggles (不规则的曲线) on a page feeds into visual memory: people might remember a word they wrote down in French class as being at the bottom-left on a page, for example.
Another one of the best-demonstrated advantages of writing by hand seems to be in superior note-taking. In a study from 2014 by Pam Mueller and Danny Oppenheimer, students typing wrote down almost twice as many words and more passages word for word from lectures, suggesting they were not understanding so much as rapidly copying the material. Hand-writing, which takes longer for nearly all university-level students, forces note-takers to synthesize ideas into their own words. This aids conceptual understanding at the moment of writing. Besides, those taking notes by hand also perform better on tests when students are later able to study from their notes.
Socrates may or may not have had a point about the downsides of writing. But no one would remember, or much less care, if his student Plato had not noted his teachings down for the benefit of later generations.
1. Why do teachers complain?| A．Because students carry laptops to class. |
| B．Because students cause distraction in class. |
| C．Because students are not focused in class. |
| D．Because students are suffering from sight loss. |
| A．It makes students understand concepts better. |
| B．It helps students develop better imagination. |
| C．It improves students’ writing ability. |
| D．It saves students’ note-taking time. |
| A．Supportive. | B．Disapproving. | C．Neutral. | D．Indifferent. |
| A．In an age of typing handwriting still matters |
| B．Handwriting helps students |
| C．Handwriting has big advantages over typing |
| D．Making the handwriting |
