The effects of coffee consumption on health have long been a subject of conflict and uncertainty.Since the 1980s,some have spoken out against coffee as harmful to health,while others have welcomed coffee for its supposed benefits to health.

    According to a scientific report,mild coffee consumption,three to five cups per day,can he taken as a healthy dietary pattern,along with other healthful behaviors.The report also says that coffee consumption helps reduce the risk of heart disease and it protects against Parkinson's disease.

    According to Dr.Donald Hensrud of Mayo Clinic,high consumption of coffee has health risks.Dr.Hensrud mentions the dangers of high coffee consumption for people with a certain illness that slows the breakdown of caffeine in the body.Some studies said that drinking two or more cups of coffee daily can actually increase the risk of heart disease in these people.

    According to conclusions from a recent study led by Dr.Gregory Marcus,a doctor from the University of California San Francisco,daily moderate consumption of caffeine,less than 4 cups,is not associated with these issues.

    Until the scientific community reaches a general agreement on the effects of coffee consumption on human health,it will be up to the individual to decide whether the benefits of drinking coffee are greater than the risks.

    When informed of these possible health benefits and harms of drinking coffee,Harwood,a high school student stated,"Even though there might be some negative effects of drinking coffee,for the most part,coffee drinking sounds good for health.Not to mention I need coffee to stay awake."

    These hotels don't have all the necessary facilities(设施),but each of them offers something different. Don't miss them if you travel to Canada.

    Sleep on a train at the Train Station Inn. This hotel is in an old train station in Nova Scotia. The owners, James and Shelley Le Fresne, use the station and the train as rooms. There are seven old train cars and there is also a restaurant in the dining car. Prices are from $89 to $169 per room or train car.

    Sleep in a jail(监狱) in the Canadian capital, Ottawa. Here, you can sleep in the old downtown Ottawa Jail Hostel. There are group or private bedrooms. There are still bars on the doors! Prices are from $ 25 to $ 65. Don't worry, there aren't any criminals(犯人）there !

    Sleep in a tepee (a tent of the American Indians) at a UNESCO World Heritage site in Alberta. At this hotel, there are guided tours and lessons in local culture. The best part: sleeping in a real tepee outside. The price is around $ 300, or $ 620 for a full package.

    Sleep in a lighthouse at the Quirpon Lighthouse Inn. This hotel is on Newfoundland's Quirpon Island. There are great views of the ocean from the windows. There are 11 private rooms in total. Prices are from $ 225 for a single to $ 350 for a suite(套房). Meals are included in the restaurant. The hotel has the traditional look and feel of the lighthouse, so there is no Internet, TV or telephones in the rooms. There are tours available, and boat tours to the island are included.

    Inner Mongolia Autonomous Region is an important ecological screen for the north of China and even the whole country. Building a green great wall to ensure China's ecological security is one of the most important things of autonomous region.

The largest ecological function zone in the north of China, Inner Mongolia has a variety of landscapes, including forests, grasslands, wetlands, rivers and lakes. In recent years, the region's environment has improved, with its forest and grassland area having increased and desert reduced.

    However, it still faces a number of challenges in ecological preservation. For instance, the region faces severe water shortages with the number of lakes dropping from 427 in 1987 to 145 in 2010. In addition to a lack of rainfall, huge water consumption in agricultural and industrial production has worsened the water shortage. Too much use of fertilizers has damaged the soil and affected the growth of grass, accelerating the expansion of the desert, which results from a lack of water.

The local government encourages planting trees on grassland as they can get more pay for trees than by growing grass. However, the trees they plant often have a low survival rate as they have a high water consumption rate. Also, to treat wetlands, some areas have planted a large number of a single tree species. This practice may damage biodiversity (生物多样性) and endanger the survival of certain animals.

Experts suggest taking the region's water resources and weather conditions into consideration in future ecological projects.

    People have different ways of dealing with a common cold. Some take over-the- counter(非处方的) medicines such as aspirin while others try popular home remedies(治疗)like herbal tea or chicken soup. Yet here is the tough truth about the common cold: nothing really cures it.

    So why do people sometimes believe that their remedies work? According to James Taylor, professor at the University of Washington, colds usually go away on their own in about a week, improving a little each day after symptoms peak, so it's easy to believe it's medicine rather than time that deserves the credit, USA Today reported.

    It still seems hard to believe that we can deal with more serious diseases yet are powerless against something so common as a cold. Recently, scientists came closer to figuring out why. To understand it, you first need to know how antiviral(抗病毒的) drugs work. They attack the virus by attaching to and changing the surface structures of the virus. To do that, the drug must fit and lock into the virus like the right piece of a jigsaw(拼图), which means scientists have to identify the virus and build a 3-D model to study its surface before they can design an antiviral drug that is effective enough.

    The two cold viruses that scientists had long known about were rhinovirus(鼻病毒) A and B. But they didn't find out about the existence of a third virus, rhinovirus C, until 2006. All three of them contribute to the common cold, but drugs that work well against rhinovirus A and B have little effect when used against C.

    "This explains most of the previous failures of drug trials against rhinovirus," study leader Professor Ann Palmenberg at University of Wisconsin-Madison, US, told Science Daily.

    Now, more than 10 years after the discovery of rhinovirus C, scientists have finally built a highly-detailed 3-D model of the virus, showing that the surface of the virus is, as expected, different from that of other cold viruses.

    With the model in hand, hopefully a real cure for a common cold is on its way. Soon, we may no longer have to waste our money on medicines that don't really work.

    A mixture of deep sorrow and anger has swept Brazilians across the country — particularly in the city of Rio de Janeiro — with the burning of their beloved Museu Nacional, or National Museum.

    By Monday morning, when I visited the site, the firemen were busy trying to enter the huge, early 19th-century neoclassical building. For all we know, everything may have been burned to ashes. Fortunately, no one, not even the four security guards who witnessed the beginning of the fire, has been injured.

    Nobody yet knows the cause of the fire, but it is the officials' irresponsibility and the funding shortages in particular, which are being blamed for this tragedy.

    Some of the museum's researchers told the press that they had been able to save some things from the exhibition rooms before the fire moved in. However, we Brazilians have lost much of the material memory of our short past. A good part of our 518 years of history, or that which had been transformed into storable objects, disappeared in just a few hours.

    The people of Rio de Janeiro were fond of taking their children  or grandchildren to the museum to show off their knowledge of the odd-looking mummies brought in from Egypt by the Emperor Dom Pedro II, a huge skeleton of a humpback whale, or the brightly coloured feathers of a headdress of the Kayapo tribe.

    When I think that I can no longer take my youngest daughter to the Museu Nacional — that is what gets me emotional. It is this feeling that has penetrated (穿透) our souls and may leave Brazilians feeling empty for a long time to come.

    (The New York Times, Oct.7) The 2019 Nobel Prize in physiology(生理学) or medicine was jointly awarded to three scientists — William G. Kaelin Jr., Peter J. Ratcliffe and Gregg L. Semenza — for their work on how cells sense and adapt to oxygen availability. The Nobel Assembly announced the prize at the Karolinska Institute in Stockholm on Monday.

    Their work established the genetic mechanisms(机制) that allow cells to respond to changes in oxygen levels. The findings have implications(启示) for treating a variety of diseases.

    Why did they win?

    "Oxygen is the lifeblood of living organisms(生物体)," said Dr. George Daley, dean of Harvard Medical School. "Without oxygen, cells can't survive." But too much or too little oxygen can be deadly. The three researchers tried to answer this question: How do cells regulate their responses?

    The investigators uncovered detailed genetic responses to changing oxygen levels that allow cells in the bodies of humans and other animals to sense and respond to fluctuations(波动), increasing and decreasing how much oxygen they receive.

    Why is the work important?

    The discoveries reveal the cellular mechanisms that control such things as adaptation to high altitudes and how cancer cells manage to hijack(攫取) oxygen. Randall Johnson, a member of the Nobel Assembly, described the work as a "textbook discovery" and said it would be something students would start learning at the most basic levels of biology education.

    "This is a basic aspect of how a cell works, and I think from that standpoint alone it's a very exciting thing." Johnson said.

    The research also has implications for treating various diseases in which oxygen is in short supply — including anemia, heart attacks and strokes — as well as for treatment of cancers that are fed by and seek out oxygen.