Next time you make yourself a hot cup of tea or coffee, you might want to let it cool down a bit before drinking.

    Researchers say letting your hot drinks cool off could help you avoid some kinds of cancer. Researchers at the International Agency for Research on Cancer (IARC) found evidence that drinks at temperatures above 65℃, when swallowed, can cause cancer of the esophagus (食道). The researchers examined findings from other studies where tea and coffee were often served at 70℃ or above. Those studies were completed in Iran, China and South America.

    In developed countries, health experts have linked esophageal cancer to smoking and alcoholic（酒精）drinks. However, this form of cancer is more common in areas where people drink beverages（饮料；酒水）at very high temperatures.

    In Europe and the United States, many people drink coffee and tea at temperatures around 60℃.And they often add milk which lowers the temperature greatly. However, tea-drinkers in Iran and mate-drinkers in South America often enjoy their beverages at closer to 70℃.

    The researchers find that South Americans not only drink their mate very hot, they also drink it through a metal straw(吸管). This sends the scalding liquid directly into the throat.

    The findings, however, are good news for coffee drinkers. In 1991, the World Health Organization listed coffee as possibly carcinogenic (致癌的).” The WHO officials have since changed their position on that listing. They now suggest that the temperature of your hot drink is a greater risk factor than the actual drink itself.

    The results suggest that drinking very hot beverages is one probable cause of esophageal cancer and that it is the temperature, rather than the drinks themselves, that appears to be responsible.

    Mandara seemed to know something big was about to happen. So she let out a yell, caught hold of her 2-year-old daughter Kibibi and climbed up into a tree. She lives at the National Zoo in Washington D. C.

    And on Tuesday, August 23rd, witnesses said she seemed to sense the big earthquake that shook much of the East Coast before any humans knew what was going on. And she's not the only one. In the moments before the quake, an orangutan（猩猩）let out a loud call and then climbed to the top of her shelter.

    “It's very different from their normal call,” said Brandie Smith, the zookeeper. “The lemurs（monkeylike animals of Madagascar）will sound an alarm if they see or hear something highly unusual.”

    But you can't see or hear an earthquake 15 minutes before it happens, can you? Maybe you can—if you're an animal. “Animals can hear above and below our range of hearing,” said Brandie Smith. “That's part of their special abilities. They're more sensitive to the environment, which is how they survive.”

    Primates weren't the only animals that seemed to sense the quake before it happened. One of the elephants made a warning sound. And a huge lizard（蜥蜴）ran quickly for cover. The flamingoes（a kind of birds）gathered before the quake and stayed together until the shaking stopped.

    So what kind of vibrations（震动）were the animals picking up in the moments before the quake? Scientist Susan Hough said earthquakes produce two types of waves—a weak “P” wave and then a much stronger “S” wave. The “P” stands for “primary”. And the “S” stands for “secondary”. She thinks the “P” wave might be what sets the animals off.

    Not all the animals behaved unusually before the quake. For example, Smith said the zoo's giant pandas didn't jump up until the shaking actually began. But many of the other animals seemed to know something was coming before it happened. “I'm not surprised at all,” Smith said.

    Modern lifestyles are generally quite different from those of our hunter-gatherer ancestors, a fact that some claim as the cause of the current rise in global obesity, but new results published July 25 in the open access journal PLOS ONE find that there is no difference between the energy expenditure(耗费) of modern hunter-gatherers and Westerners, casting doubt on this theory.

    The research team behind the study, led by Herman Pontzer of Hunter College in New York City, along with David Raichlen of the University of Arizona and Brian M. Wood of Stanford measured daily energy expenditure among the Hadza, a population of traditional hunter-gatherers living in the open Savannah of northern Tanzania. Despite spending their days hiking long distances to seek for wild plants and game, the Hadza burned no more calories each day than adults in the U.S. and Europe. The team ran several analyses accounting for the effects of body weight, body fat percentage, age, and gender. In all analyses, daily energy expenditure among the Hadza hunter-gatherers was indistinguishable(难以区分的) from that of Westerners. The study was the first to measure energy expenditure in hunter-gatherers directly; previous studies had relied entirely on estimates.

    These findings overturn the long-held assumption that our hunter-gatherer ancestors expended more energy than modern populations, and challenge the view that obesity in Western populations results from decreased energy expenditure. Instead, the similarity in daily energy expenditure across a broad range of lifestyles suggests that habitual metabolic(新陈代谢的) rates are relatively constant among human populations. This in turn supports the view that the current rise in obesity is due to increased food consumption, not decreased energy expenditure. It means we have more to learn about human physiology(生理学) and health, particularly in non-Western settings.

    "These results highlight the complexity of energy expenditure. It's not simply a function of physical activity," says Pontzer.” Our metabolic rates may be more a reflection of our shared evolutionary past than our diverse modern lifestyles."

    It was many years ago. I was a young dad sitting on the couch reading a fairy tale to my little girl. She sat next to me with her head on my arm as I told the tale. When it came to the end I finished with those famous words: "And they lived happily ever after." As I looked over to her with her wavy(鬈曲的), brown hair and big, innocent eyes I could see the smile on her face and I never wanted it to end. Then it dawned on me that the ending of the book was what I wanted for her. I wanted her to "live happily ever after".

    Still, deep in my heart I knew that this couldn't always be so. I knew that there would be times when her heart was broken. I knew there would be times when she cried in grief and I couldn't comfort her. I knew there would be times when all she felt was fear, sadness, sorrow, and despair. As I stroked her hair and smiled at her I hoped that those times would be brief and that she would have joy in her life more often than not. Living happily ever after, though, seemed out of the question.

    It takes me a lot of years to realize that it is possible to live happily ever after. You just have to do it "one day at a time". Happiness you see isn't some reward that you get at the end of your journey. Happiness isn't something that depends on what life you own. Happiness is something you create in your life choice by choice and day by day.

    The truth is happiness comes when you love. Love is a gift from God. It is love that mends broken hearts. It is love that heals grief. It is love that gives us joy. Choose to "live happily ever after, one day at a time".

    The Hong Kong-Zhuhai-Macau Bridge, the world's longest sea-based project, comprises four parts: a 22.9-kilometer steel bridge, two artificial islands, a submerged sea tunnel extending for 6.7 kilometers, as well as leading bridges that connect the bridge to the cities.

    For a bridge project, designers prefer to build all the structure on the ground, and only choose the tunnel when there is no alternative. However, for the HZMB, the most practical design is to integrate bridge, island and tunnel to form a complete cross-sea channel.

    "The Pearl River Estuary （河口）holds a world-level shipping channel. Smooth traffic should be guaranteed. And the location is near the Hong Kong International Airport. With about 2,000 flights taking off and landing at the airport, the bridge cannot be built too high for safety reasons, said Meng Fanchao, chief designer of the project. ^"But you cannot have a submerged sea tunnel without any support. That forced us to build the artificial islands."

    Chinese engineers declared a trail in installing deep-immersed tunnel tubes. There is no model for us to refer to as all the cases are shallow-buried tubes, said Meng.

    "For lack of experience, the installation of the first tube lasted for 96 hours," said Yin Haiqing, deputy manager of the Project Management Department. "Everyone was exhausted when we made it."

    The 6.7-kilometer tunnel is the world's longest submerged sea tunnel.

    Two artificial islands, covering an area of 200,000 square meters, help create a smooth transition between bridge sections and tunnels. Different from traditional island, the engineers put 120 steel cylinders （圆柱）with a 22-meter diameter （直径）into the seabed, make out the shape of an island, and fill the island with soil. It is an innovative way they adopted to build the artificial island, making it firmer, more efficient and friendly to the marine ecology.

    The HZMB provides a fixed link between the two Chinese economic centres Hong Kong and Macau and the mainland of China at Zhuhai.

    "What kind of rubbish are you?" This question might normally cause anger, but in Shanghai it has aroused complaints over the past week. On July 1st the city introduced strict rubbish-sorting regulations as a model for the country. Residents must divide their waste into four separate categories and throw it into specific public bins. They must do so at scheduled times, when monitors are present to ask the nature of one's rubbish, otherwise, they will face fines or worse.

    Shanghai authorities are responding to an obvious environmental problem. It generates 9 million tonnes of garbage a year, more than London's annual output and rises quickly. But like other cities in China, it lacks a recycling system. Individuals who fail to recycle could be fined up to 200 yuan (＄29). For repeat, the city can add black marks to their credit records, making it harder for them to obtain bank loans or even buy train tickets.

    Some object to this. Peng Feng of the Shanghai Academy of Social Sciences warns that the use of the credit system is overkill, raising a risk that officials will abuse their power. But others say a tough campaign is necessary. "Slowly people will get used to it," says Li Changjun of Fudan University.

    Many residents support recycling but are frustrated by the details. Rubbish must be divided according to whether it is food, recyclable, dry or harmful, the distinctions among which can be confusing, though there are apps to help work it out. Some have complained about the rules surrounding food waste. They must put it straight in the requisite public bin, forcing them to tear open plastic bags and toss (撕开) it by hand. Most upsetting are the short windows for throwing rubbish, typically a couple of hours, morning and evening. Along with the monitors at the bins, this means that people go at around the same time and can keep an eye on what is being thrown out; no one wants to look bad.