On Monday, the Centers for Disease Control and Prevention predicted that 42% of Americans could be overweight by 2030. Our expanding waistlines lead to not only a medical problem, but according to a recent article In The New York Times, it could also endanger personal safety in some situations—in an airplane crash, for example.

    The New York Times' Christen Negroni reports that engineers and scientists are questioning whether airplane seats are adequately constructed to protect overweight travelers. Government standards for airplane seat strength（强度）— first set moe than 60 years ago — require that the seats be made for a passenger weighing 170 pounds (77kg). Today, the average American man weighs nearly 194 pounds (88kg) and the average woman 165 pounds (75kg). Negroni reports:

    “If a heavier person completely fills seat, the seat is not likely to behave as intended during a crash,” said Robert Salazar, the leading scientist at the Center for Applied Biomechanics at the University of Virginia. “The energy absorption that is built into the aircraft seat is likely to be overpowered and the passengers will not be protected properly.”

    “Nor would the injury be limited to that passenger only,” Dr. Salzar said. “If a seat or a seat belt fails,” he said, “those people who are seated nearby could be endangered from 'the uncontrolled movements of the passenger'.”

    Most complaints about airplane seats focus on their lack of comfort and high ticket price, and whether overweight passengers should be made to buy two seats. But The New York Times' article brings up another reason to feel anxious about flying. Investigators of the issue got in touch with the airplane seat and seat belt makers, but they refused to comment on the problem. Experts agreed that crash testing should be done with overweight dummies （人体模型）. Both airplane seats and seat belts should be tested, they said.

    Fortunately, however, according to Nora Marshall, a senior adviser at the National Transportation Safety Board, the board's investigators have never seen an accident involving a commercial plane in which the weight of a passenger was a problem.

根据短文内容，选择最佳答案，并将选定答案的字母标号填在题前括号内。

    Researchers continue to show the power behind our sense of smell. Recent studies have found, among other things, that the smell of foods like pizza can cause uncontrollable anger in drivers on roads.

    The review explains that smell is unique in its effects on the brain. According to Conrad King, the researcher who carried out the review, “more than any other senses, the sense of smell goes through the logical part of the brain and acts on the systems concerned with feelings. This is why the smell of baking bread can destroy the best intentions of a dieter.”

    Smell, which dictates(决定) the unbelievable complexity of food tastes, has always been the least understood of our senses. Our noses are able to detect up to 10,000 distinct smells. Our ability to smell and taste this extremely large range of smells is controlled by something like 1,000 genes (基因), which make up an amazing 3% of the human genome. Researchers Richard Axel and Linda Buck were together awarded a Nobel Prize in 2004 for their ground-breaking research on the nature of this extraordinary sense. These two scientists were the first to describe the family of 1,000 olfactory (嗅觉) genes and to explain how our olfactory system works.

    According to one study in the research review, smelling fresh pizza or even the packaging of fast foods can be enough to make drivers feel impatient with other road users. They are then more likely to speed and experience uncontrollable anger on roads. The most reasonable explanation is that these can all make drivers feel hungry, and therefore desperate to satisfy their appetites.

    In contrast, the smells of peppermint and cinnamon were shown to improve concentration levels as well as reduce drivers' impatience. Similarly, the smells of lemon and coffee appeared to promote clear thinking and mental focus.

    However, the way genes regulate smell differs from person to person. A study by researchers in Israel has identified at least 50 olfactory genes which are switched on in some people and not in others. They believe this may explain why some of us love some smells and tastes while others hate them. The Israel researchers say their study shows that nearly every human being shows a different pattern of active and inactive smell-detecting receptors.

    Red leaves are a symbol of autumn. Enjoying red leaves in the clear, refreshing autumn weather is indeed a good choice.

    Now let's have a look at the best red leaves around China and the beauty of autumn.

    Destination 1

    With different red colors, the Red Leaf Valley extends (延伸) more than 50 kilometers from Jiefang village in Qingling town to Yanjiang village in Songjiang town, Jilin province, Northeast China. Leaves are like different red pigments (颜料), including Chinese red, orange red, ruby red and bright red.

    Best time: October

    Destination 2

    Tachuan or Tashang village is in Huangshan city, Anhui province, East China. The beautiful autumn scenery there is known as one of the four best in China. The red leaves and clear spring add beauty to traditional houses, offering material for photography lovers.

    Best time: early to late November

    Destination 3

    As a result of low temperatures, maple leaves in areas south of the Yangtze River are like shy girls, gradually showing their beauty, turning from green to gold, gold to orange and finally to red. And as it changes slowly, different colors can be seen on the same trees called "colorful maple trees". Viewing at the mountainside is the best choice.

    Best time: October to November

    Destination 4

    For Guangdong province in South China, autumn always comes a little late and lasts longer. Through the end of January, you can see the red leaves any time you want. If you feel pity at saying good-bye to red leaves in North China, you can head to South China to view the beautiful scenery again.

    Best time: end of November to end of January

    Growing up, I was an extremely reserved(腼腆的) boy. I didn't have many friends in primary and middle school and rarely opened up to anyone. I didn't even ask my teacher questions in class. I was scared of the world and the people around.

    As a child, I was scared to do anything without my parents mainly because I was afraid that I would do it badly. I was getting good grades and was well-behaved, but I wasn't happy. It was my belief that I was, for some reason, unable to do the things the others kids could do. I felt inadequate.

    While in my second semester of college, I ran into some information on the Internet about something called social anxiety. I didn't really know much of the disorder. Thus I began to read about some of the symptoms and realized that social anxiety was the thing that hurt me so much.

    It is common knowledge that people with social anxiety experience nervousness in social situations. What a lot of people don't know is that one of the main causes of social anxiety is negative thinking. People having a negative idea of themselves often think that they are ugly or stupid.

    I realized what I was truly afraid of: not being good enough. I was afraid that people would look at me and would not like what they saw; I was scared of rejection. To help deal with these problems, I began to practice meditation(沉思) and other mindfulness exercises. My mind slowly began to change.

    I realized that everyone, from star athletes to noble prize winners, experiences fear in their lives. Whether people are afraid of heights, planes, spiders, or talking to girls, we all experience anxiety and fear. There is no reason for anyone to feel excluded(排除在外的) because something scares them. People with anxiety disorders might have "problems", but there is nothing wrong with them as people. They are just as humans as everyone else.

    Rich countries are racing to dematerialise payments. They need to do more to prepare for the side-effects.

    For the past 3,000 years, when people thought of money they thought of cash. Over the past decade, however, digital payments have taken off— tapping your plastic on a terminal or swiping a smartphone has become normal. Now this revolution is about to turn cash into an endangered species in some rich economies. That will make the economy more efficient—but it also causes new problems that could hold back the transition(转型).

    Countries are removing cash at varying speeds. In Sweden the number of retail cash transaction per person has fallen by 80% in the past ten years. America is perhaps a decade behind. Outside the rich world, cash is still king. But even there its leading role is being challenged. In China digital payments rose from 4% of all payments in 2012 to 34% in 2017.

    Cash is dying out because of two forces. One is demand— younger consumers want payment systems that plug easily into their digital lives. But equally important is that suppliers such as banks and tech firms (in developed markets) and telecoms companies (in emerging ones) are developing fast, easy-to-use payment technologies from which they can pull data and pocket fees. There is a high cost to running the infrastructure behind the cash economy—ATMs, vans carrying notes, tellers who accept coins. Most financial firms are keen to abandon it, or discourage old-fashioned customers with heavy fees.

    In the main, the prospect of a cashless economy is excellent news. Cash is inefficient. When payments dematerialise, people and shops are less open to theft. It also creates a credit history, helping consumers borrow.

    Yet set against these benefits are a couple of worries. Electronic payment systems may risk technical failures, power failure and cyber-attacks. In a cashless economy the poor, the elderly and country folk may be left behind. And a digital system could let governments watch over people's shopping habits and private multinationals exploit their personal data.

Researchers at MT created a high-tech pill that starts to vibrate(震动) once it makes contact with liquid in the user's stomach and make him or her feel full. The pill was reportedly thought up by Shriya Srinivasan, currently an assistant professor of bioengineering at Harvard University.

VIBES, short for Vibrating Ingestible BioElectronic Stimulator，was only recently made public in a study published in the Science Journal, but it is already being announced by the media as the future of weight loss. Although it has yet to be tested on humans, trials on pigs have achieved very hopeful results. After about 30 minutes of VIBES activity, pigs consumed on average almost 40 percent less food in the next half hour than they did without the smart pill. Apparently, the revolutionary device works by activating stretch receptors in the stomach, modeling the presence of food. This in turn signals the hypothalamus(下丘脑) to increase the levels of hormones that make us feel full. The vibrating stimulator, which is about the size of a vitamin pill, is powered by an encased battery and activated either by the gastric fluid(胃液) breaking down a coat around the pill, or by an incorporated timer. After producing the desired effect, the pill exits the body with other solid waste.

The good news is that it is expected to have a cost in the cents to one dollar range, and researchers say that it may eventually be possible to implant the stimulator and thus remove the need for people to constantly swallow it.

"Our study demonstrates the effectiveness of a low-cost, non-operative intervention to reduce food intake and calorie consumption. The device functions effectively in the stomach and leading to fullness," said Giovanni Traverso, co-author of the study. "The device has the potential to revolutionize options for weight loss treatment. However, future studies will need to explore the physiological effects of the device before it's available for patients."

Researchers are now exploring ways to scale up the producing of VIBES capsules which could enable clinical trials in humans.