Recently, online hike-sharing has become the new favorite in China. In major cities, bikes in, yellow, orange, blue, white and green, can be seen almost everywhere on the street. It seems that these bikes appeared suddenly, adding a new beautiful scenery to Chinese cities.

    Both the market and the public welcome online bike-sharing, but is it really a promising business? Well, it depends. After all, online bike-sharing platforms can never get away with huge operating cost and uncertain government policy.

    Some theorists might say that online bike-sharing platforms can earn a fortune simply through deposit. Since users will always need to rent bikes, their deposit will always be kept to online bike-sharing platforms.

    However，although online bike-sharing platforms may be able to use the deposit for other purposes at the primary stage, they will have to set up a special account, so that the deposit shall be used specially for its designated (指定的) purpose. As the market gets increasingly mature, they will have to do so whether to be responsible for users or in consideration of possible government regulations.

    Now that online hike-sharing platforms can，t make profit through deposit，how can they become profitable as fiercer market unfolds? Although Hu Weiwei, CEO of Mobike, stated in an article that she would take Mobike as charitable(慈善的) project if she failed, running a startup is absolutely different from managing a charity organization. After all , she has to pay back investors' billions of investment(投资).

    To make profit, online bike-sharing platforms might have toincrease rent fee for each trip, just as Didi did

    From this aspect, it might be a really good business. If we consider full screen ads fee, recommendation fee for business owners, etc. , its annual income might reach at least RMB 15 billion. If we consider the huge operation cost, including bike repairs，bikes' service life and labor cost, there might not be much net profit left. After all, offline operation cost has always been an unbearable burden for such internet plus mode-based startups.

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Like many Czechs (捷克人), Lukáš Berný, 38, enjoys going out to the pub with his friends for conversation and a few beers. "I don't drink every day," he says. "I think about three times a week. When I go out, I usually have five to six beers at a time, about the same as my friends." The beers are half-liters, or 500ml each.

    If a half-liter of four-percent beer contains 16g of pure alcohol（酒精）, Berný and his friends are drinking 80 to 96 grams of pure alcohol on each outing. The Czech Republic's National Institute of Public Health, however, suggests that men take in fewer than 24g of pure alcohol per day; women, fewer than 16g.

Medical experts in over 40 countries around the world have agreed that drinking "too much" can cause harm. What they can't seem to agree upon is just how much is "too much." National safety levels are quite different, from a limit of 10g a day in the Netherlands to Denmark's 60g.

There are a number of reasons for this. Dr. Larry Altshuler, a medicine expert for the Cancer Treatment Centers in Tulsa, explains that while everything is based on research, "Every group, race, and gender responds to alcohol differently."

Also, researchers aren't using the same models or methods. He adds, "It can be like apples and oranges. How do you measure alcohol? Units, drinks, bottles or cans? What's the alcohol content（含量）? Is it light or heavy?" While a half-liter of four percent beer contains 16g of pure alcohol, a half-liter of five percent lager contains 20g.

Constance Scharff, a director of Addiction Research at Cliffside Malibu Treatment Center in California, says she believes the reason "is largely cultural." "But the evidence is clear that the more you drink, the more likely you are to develop alcohol-related health problems."

    Most people looking for ways to quit smoking worry about weight gain, and with good reason. Smokers who quit tend to pack on an average of 5 pounds after they stop smoking cigarettes. A new study, published by the journal Science, explains why this happens.

    The new research explains that nicotine appears to combine with appetite-regulating neurons (调节食欲的神经元) in the brain, besides the receptors (感受器) that bring about addiction. These neurons help regulate how much food gets consumed, but under the influence of nicotine, they lose their self-control. This is why when smokers quit, they tend to eat more and gain weight.

    The researchers believe that their discovery will lead to the development of drugs that aim at nicotine receptors on brain cells that control appetite. In the future, weight gain may no longer be a reason for smokers to delay the decision to kick the habit, but that's no reason to wait. Nicotine-replacement treatment, while not for everyone, can help. Here are a few more ways to quit smoking and stay slim.

    Drink water. To improve metabolic (新陈代谢的) rates, make half of those glasses ice water. Juice can be too high in calories, something you'll want to keep an eye on your journey toward being a slimmer non-smoker. Plan your snacks. Healthy snacks help keep your metabolism working, so you continue to burn calories while stopping wild hunger pain, or fake hunger.

    Keep moving. Exercise kills two birds with one stone. It helps you burn calories and prevents you from eating when you're not truly hungry. It's also a feel-good stress reliever (缓解物). Focus on your fitness and how being healthy makes you feel. Make exercise a goal and think of quitting as your reward for being physically fit.

    The largest genetic study of mosquitoes has found their ability to resist insecticides(杀虫剂) is evolving rapidly and spreading across Africa, putting millions of people at higher risk of contracting malaria(疟疾).

British scientists who led the work said mosquitoes' growing resistance to control tools such as insecticide-treated bed nets and insecticide spraying, which have helped cut malaria cases since 2000, now threatens "to disturb malaria control" in Africa.

    "Our study highlights the severe challenges facing public efforts to control mosquitoes and to manage and limit insecticide resistance," said Martin Donnelly of the Liverpool School of Tropical Medicine, who worked on the study with a team from Britain's Wellcome Trust Sanger Institute.

    Latest World Health Organization (WHO) data show that 216 million people were infected last year with the malaria parasite(寄生虫), which is transmitted by blood-sucking Anopheles mosquitoes. The disease killed 445,000 people in 2016, and the majority of them were children in sub-Saharan Africa.

    To understand how mosquitoes are evolving, the researchers sequenced the DNA of 765 wild Anopheles mosquitoes taken from 15 locations across eight African countries. Their work, published in the journal Nature on Wednesday, created the largest data resource on natural genetic variation for any species of insect.

    Analyzing the data, the scientists found that the Anopheles gamblae mosquitoes(冈比亚疟蚊)were extremely genetically diverse compared with most other animal species. This high genetic diversity enables rapid evolution, they said, and helps to explain how mosquitoes develop insecticide resistance so quickly.

    The data also showed the rapid evolution of insecticide resistance appeared to be due to many previously unknown genetic variants(变体)within certain genes. The scientists said these genetic variants for insecticide resistance were not only emerging independently in different parts of Africa, but were also being spread across the continent by mosquito migration.

    Michael Chew, an expert at Britain's Wellcome Trust global health charity which helped fund the research, said the finds underlined the importance of pushing scientific research ahead to control malaria.

Global efforts to control malaria through effective vaccine, insecticides and the best drug combinations require urgent, united action by scientists, drug companies, governments and the WHO.

    The Great Depression that followed the stock market crash of 1929 saw hundreds of thousands of Americans out of work. In the years of great fear and depression, a lot of American citizens looked desperately to the federal government for assistance. Of all the programs designed by President Roosevelt when he took office in 1932, few were more criticized - or had more lasting impact - than the Work Projects Administration, better known as the WPA.

    The intention of the WPA, which functioned from 1935 to 1943, was to design and administer public works projects to help relieve unemployment. The majority of these projects involved historic or artistic attempts. The WPA's Writers Project, for example, was responsible not only for such practical works as state guidebooks but also for the collection of historically valuable oral histories. Over 2,900 of these records were collected in 24 states. They provide an irreplaceable firsthand account of people's diets, customs, celebrations, and political and religious beliefs at the time.

    The artworks created through the Federal Arts Project are one of the WPA's most lasting achievements. Out - of - work painters, both famous and unknown, created paintings that beautified schools, libraries, and government buildings, WPA photographers traveled across the country recording the hardships of life on small rural farms. When the United States entered World War Ⅱ in 1941, WPA artists were enlisted to produce posters supporting the war effort. Many WPA artworks, including hundreds of small drawings picturing scenes of everyday life, still exist today.

All students are expected to read and learn the School Rules. These rules aim to make each student aware of the value of self-control, orderliness and the need to develop a sense of responsibility for their own behavior and for the larger community of which they are a part.

Dress Regulations

The School expects its students to wear their full school uniform correctly and with pride. It is our expectation that uniform and shoes will be clean and in good repair. Boys' hair should be combed and of an acceptable length (not over the collar, ears or eyes), with no artificial coloring. Girls' hair should be of a natural color. Shoulder-length hair must be tied back.

Absence, Illness and Punctuality

All students must be at school on time. If late, the student must sign in the late book in the General Office. Parents are asked to inform the school if their child is absent by 8:30 am on the day of absence. A written note from a parent explaining the absence MUST be provided to the General Office the day after return.

Should a student be ill during school hours he is to go straight to the School Medical Center. The sister will then take appropriate action.

Safety

◆ Proper behavior is expected within and around buildings and on the sporting field at all times.

◆ Students are not to enter laboratories, language rooms, the Technics and music rooms until invited to do so by teachers.

◆ The riding of bicycles or skateboards is prohibited along the front drive. Students riding bicycles must wear an approved bicycle helmet.

◆ No knives, explosives or dangerous materials may be brought into the school or boarding houses.

◆ Students are forbidden to interfere with fire safety equipment. An automatic fine will be imposed if this occurs.