In its early history, Chicago had floods frequently, especially in the spring, making the streets so muddy that people, horses, and carts got stuck. An old joke that was popular at the time went something like this: A man is stuck up to his waist in a muddy Chicago street. Asked if he needs help, he replies,“No, thanks. I've got a good horse under me.”

    The city planners decided to build an underground drainage(排水) system, but there simply wasn't enough difference between the height of the ground level and the water level. The only two options were to lower the Chicago River or raise the city.

    An engineer named Ellis Chesbrough convinced the city that it had no choice but to build the pipes above ground and then cover them with dirt. This raised the level of the city's streets by as much as 12 feet.

    This of course created a new problem: dirt practically buried the first floors of every building in Chicago. Building owners were faced with a choice: either change the first floors of their buildings into basements, and the second stories into main floors, or hoist the entire bulidings to meet the new street level. Small wood-frame buildings could be lifted fairly easily. But what about large, heavy structures like the Tremont Hotel, which was a six-story brick building?

    That's where George Pullman came in. He had developed some house-moving skills successfully. To lift a big structure like Tremont Hotel, Pullman would place thousands of jackscrews(螺旋千斤顶) beneath the building's foundation. One man was assigned to operate each section of roughly 10 jackscrews. At Pullman's signal each man turned his jackscrew the same amount at the same time, thereby raising the building slowly and evenly. Astonishingly, the Tremont Hotel stayed open during the entire operation, and many of its guests didn't even notice anything was happening.

    Some people like to say that every problem has a solution. But in Chicago's early history, every engineering solution seemed to create a new problem. Now that Chicago's waste water was draining efficiently into the Chicago River, the city's next step was to clean the polluted river.

    Not many years ago, a wealthy and rather strange old man named Johnson lived alone in a village in the south of England. He had made a lot of money in trading with foreign countries. When he was seventy-five, he gave £ 12,000 to the village school to buy land and equipment for a children's playground.

    As a result of his kindness, many people came to visit him. Among them was a newspaperman. During their talk, Johnson said that he was seventy-five and expected to live to be a hundred. The newspaperman asked him how he managed to be healthy at seventy-five. Johnson had a sense of humor. He liked whisky and drank some each day. "I have an injection (注射) in my neck each evening." He told the newspaperman, thinking of evening glass of whisky.

    The newspaperman did not understand what Johnson meant. In his newspaper he reported that Johnson was seventy-five and has a daily injection in his neck. Within a week Johnson received thousands of letters from all over Britain, asking him for the secret of his daily injection.

    The cost of living in countries like the U.S., Britain, Australia or France has skyrocketed (飞涨) in recent years. However, if you are willing to leave your country and explore life in other areas, there are many countries boasting an extremely cheap and low cost of living. Check out the following countries when planning your next move.

    Ecuador

    Ecuador is similar to the United States in many ways, and as a result has become a popular American getaway. They even use the U.S. dollar for their currency. In this country, it is cheaper to eat out every day than cook for yourself on a budget in the U.S. You can even buy a property for around $50,000 and hire someone to tend to it while you are away.

    Mexico

    Although the country is known for its poverty-ridden streets, there are many wealthier areas that provide every facility you might need. You can live off a mere $700 to $800 a month in Mexico, and this includes rent for a nice place, facilities, food, and any sightseeing.

    Argentina

    Argentina has been a popular tourist destination for many years. It has great restaurants, a rich history, and many places to explore. Not to mention, it is not very expensive to live there. A decent sized home can cost around $139,000, which is relatively cheap in relation to homes in the United States.

    Vietnam

    Vietnam has also become a popular tourist destination in recent years. There are many million dollar luxury homes by the beach, but you can find a modest flat or small home for around $25,000 to $50,000 if you search in the right areas.

    The impression you make at the beginning of an interview is very important. Employers often decide to hire someone in the first three minutes of the interview. They judge you by your appearance, attitude and manners.

    A friendly smile when you walk into the room is important. A smile shows a confident and positive attitude. When you introduce yourself, make eye contact with the interviewer. Some interviewers offer a handshake. Others don't.

    Try to be as natural as possible. But pay attention to your body language. The way you sit, walk, gesture, use your voice and show feelings on your face is all part of your body language. It makes the interviewer know how you feel about yourself and the situation you are in. Are you feeling positively about yourself？Your abilities? Your interest in the job？

    Speak clearly and loudly enough. Show interest and enthusiasm in your voice. When you speak, look at the interviewer. Also, don't say negative things about yourself, or former employer.

    Listen to questions carefully. If you don't understand a question, ask the interviewer to repeat or explain:

    "I'm sorry, but I didn't catch that."

    "Almost everyone is nervous in a job interview. Interviewers know that. They don't expect you to be totally calm and relaxed. But they expect you to try to control your nervousness. They expect you to show confidence in your ability to do the job.

    At the end of the interview, thank the interviewer for her or his time. It's a good idea to send a short thank-you letter right after the interview, or deliver it by hand.

    Phone the company if you have not heard anything after one week. Ask if they have made a decision about the job.

Good luck!

As the world deals with the rising temperatures brought by climate change, the demand for cooling solutions in hot, dry regions becomes increasingly pressing. However, traditional air conditioning systems produce massive greenhouse gases and use lots of energy.

Facing these challenges, a research team from McGill University, UCLA, and Princeton have found an inexpensive, sustainable cooling method. Their approach not only offers a solution for cooling but also promises to address the problem of heat waves during electricity blackouts.

The researchers set out to achieve a new standard in passive cooling (无动力制冷) within naturally conditioned buildings in hot climates such as Southern California. They aimed to address an important question: how can passive cooling techniques outperform traditional air conditioning units and improve indoor comfort?

The key to this breakthrough lies in harnessing the potential of radiative (辐射的) cooling materials, specifically in the context of housing design. Traditionally, such materials have been employed to prevent roofs(屋顶) from overheating and improve heat rejection from cooling systems. However, the research team recognised that there is under-explored potential in integrating these materials into building design — they can not only remove waste indoor heat but also drive regular and healthy air changes.

Lead author Remy Fortin stated, "We found we could maintain air temperatures several degrees below the surrounding temperature."Remarkably, they achieved this success without giving up a healthy airing. This was never a piece of cake, considering air exchange can unintendedly introduce heat into the building when the goal is to keep the inside cooler than the outside.

The researchers are hopeful that their findings will be used to positively impact communities suffering from climatic heating and heat waves. Salmaan Craig, the principal researcher expressed their expectations: "We hope that materials scientists, designers, and engineers will be interested in these results and that our work will inspire more broader thinking for how to integrate breakthroughs in radiative cooling materials with simple but effective solutions."

Born in 1958, in south China's Guangxi Zhuang Autonomous Region, Huang Danian had an interest in geophysics from {#blank#}1{#/blank#}early age. He devoted his life to science, making many sacrifices(牺牲) along the way and{#blank#}2{#/blank#}(final) went to the United Kingdom for further study in 1993.

In 2008,{#blank#}3{#/blank#}(drive) by the idea that he needed to contribute{#blank#}4{#/blank#}his country, he gave up a good job and a life there and returned home. Huang{#blank#}5{#/blank#}(invite) to be the chief scientist of China's {#blank#}6{#/blank#}(big)deep-Earth exploration programme at Jilin University in Changchun, in northeast China. The programme aimed to install (安装) high-tech {#blank#}7{#/blank#}(camera) on aircraft, ships and satellites, {#blank#}8{#/blank#}would enable scientists to see through the Earth's crust(地壳). His efforts soon{#blank#}9{#/blank#}(pay) off. China narrowed the gap with the developed countries in obtaining accurate data on deep-Earth exploration. Thanks to a number of devoted scientists, such as Huang. (China is now becoming a leading power in this technology.）

Huang died at the age of 58. A bright star in the world of science had fallen, {#blank#}10{#/blank#}(leave) the scientific community in grief.