Have you been told you have penicillin allergy? Did your parents tell you that you had a reaction as an infant or child, so you should never take it again? Has it been so long since you had a reaction to penicillin that you don't remember what happened? If you fit any of these descriptions or are just not sure if you have penicillin allergy, there's good news for you: Chances are, you probably don't have it.

    Between 10 to 20 percent of Americans believe they have a penicillin allergy, but a recent study at Mayo Clinic found that only 10 percent of those people are truly penicillin allergic. In other words, 9 out of 10 people who think they have penicillin allergy are avoiding it for no reason. Even in people with documented allergy to penicillin, only about 20 percent are still allergic 10 years after their initial allergic reaction. It's not necessarily a permanent condition.

    Why is this important? Aren't there many other antibiotics you can use if you have penicillin allergy? Penicillin has been around since 1928. Penicillin and its related medicines include amoxicillin, methicillin and amoxicillin-clavulnate. These medicines are highly effective treatments for many bacterial infections, such as strep throat and ear infections. Of course, there are alternative antibiotics, but these are often much more expensive and carry a higher risk of side effects. Typically, these alternative antibiotics are broad-spectrum, meaning they fight many types of bacteria, both good and bad. That can lead to development of drug-resistant bacteria, or deadly “superbugs”. This increases the risk for all of us in the future of not having an effective antibiotic to treat our infection.

    How do you find out if you have penicillin allergy? Board-certified allergists can test you. First, the allergist will get a history from you about your possible allergy. Typical questions include: How long ago did you have the reaction? What type of reaction occurred, and how soon after you took the penicillin did the reaction appear? The testing is done on the forearm by pricking the skin with a needle. If the results are negative and there is no reaction, penicillin will be injected in the skin. These tests are not painful, and results are available in 15 minutes. A positive reaction may lead to some swelling and itching where the test was placed, which usually goes away within an hour.

    In very rare cases, an allergic reaction occurs. This can include hives, swelling, wheezing and/or difficulty breathing. The allergist is trained to treat this rare condition quickly if it happens. If all skin testing is negative, you may be given an oral dose of penicillin in the office. The oral drug challenge is used to verify that you don't have penicillin allergy. Usually, you'll be observed in the office for 30 minutes to make sure you have no problems.

    If you find out you don't have a penicillin allergy, notify your physicians that it's now safe for you to take penicillin. They can take “penicillin allergy” off your chart for good!

    Antarctica, with its seemingly endless icy beauty, is one place where one look is worth a thousand words. My own dream to see it came true last January when I joined the sixth exploration crew(考查队) of the China National Marine Bureau. We spent 10 days connecting flights to reach our goal, but finally arrived at the Great Wall Station on Antarctica on the eve of Chinese New Year.

    There are only two seasons in Antarctica: winter and summer. You get polar nights in winter and polar days in summer. Day is longer than night in summer, and the temperature often reaches below zero. Luckily, there are no snowstorms in summer, which makes it the best season to travel. What I imagined before starting for Antarctica was a world of ice, storms, endless cold and loneliness. When I stopped on Antarctica for the first time, however, I saw rich, energetic and beautiful scenery that was beyond anything I had imagined.

    We only spent 11 days at the South Pole, but every minute was spent taking pictures and losing our heart to the wonderland. Beauty enveloped us as we watched the world around us. The mountains, oceans, ice, snow, sky, earth and people all seemed to have their own stories.

    Rocks from Antarctica are considered valuable. Unfortunately, I didn't bring one back. However, my heavy bags full of films are certainly worth that. It is in these pictures that the true Antarctica comes alive.

    Some international languages are widely used for many purposes. Some minority languages will die out and some nations tend to keep minority languages. I reckon that most common used international languages ease our life quality and communication with different nationalities. On the other hand, we need to help improve minority languages.

    There are many languages in the entire world but two or three minority languages die out each year. Some countries try to save dying languages. For instance, Australian Government created a project to save the language and culture of Maori who are Australian aborigines. And there are other projects to keep minority languages such as American Indian language.

    However, the worldwide job market usually requires candidates who can speak English or other international languages. People who cannot speak lingua franca (共通语) could hardly be promoted at work. For example, some companies need an employee who can deal with foreign companies. So most people tend to learn at least one international language that helps them to find a better job.

    Therefore, world needs one common lingua franca that should be spoken in any country. Consequently, one common language should be a required subject in every school. So anyone speaking one common language can travel without worries to any point of the world and trade their products. People will not be forced to learn many languages.

    In conclusion, we should help minority nations to keep their languages for the cultural diversity. To ease the worldwide communication among nations, we should create a common language and provide courses of it. As a result, no one will face a language issue.

    Let's face it. No one drinks diet sodas for the taste. People drink diet sodas in the hope that it will help them lose weight or at least keep them from gaining it. Yet it seems to have exactly the opposite effect, according to a new study.

    Researchers from the University of Texas said those who drank two or more diet sodas a day had waist size increases that were six times greater than those who didn't drink diet sodas. "What we saw was that the more diet sodas a person drank, the more weight they were likely to gain," said Sharon Fowler.

    The study was based on data from 474 participants in a large, ongoing research project, where the participants were followed for nearly 10 years.

    While the findings are surprising, they also offer some explanations.

    Nutrition expert, Melanie Rogers, who works with overweight patients in New York, has found that when patients are switched from regular to diet sodas, they don't lose weight at all. "We weren't seeing weight loss necessarily, and that was confusing to us," said Rogers.

    So why would diet soda cause weight gain? No one knows for sure yet, but it could be that people think they can eat more if they drink diet sodas, and so over-compensate(补偿) for the missing calories.

    A related study found some sweeteners (甜味剂) raised blood sugar levels in some mice. "Data from this and other potential studies suggest that the promotion of diet sodas and artificial sweeteners may be risky," said Helen P. Hazuda, professor at the University of Texas's school of medicine. "They may be free of calories, but not of consequences."

Fishy Weather Conditions

    Laj amanu, Australia, is a dry little town, sitting right on the edge of the Tanami desert. Can you imagines how surprised were people when live fish rained down on them from a dark gray cloudy. It happens that there are similar cases in England and Honduras.

    How do clouds make fishy. The simple answer is that they don't. There is a particular weather phenomenon(现象)called a waterspout. A waterspout is just like a tornado, only it forms above oceans, lakes, or rivers. Like a tornado, a waterspout moves in a circle at high speeds. When it moves above the water, it tends to carry the fish with it, as well as frogs or other small plants or animals.

    Scientists couldn't work it out at first. To make matters stranger still, the fish in Honduras were very much alive when they rained down to the ground, but they were all blind. In England and Australia, it rained fish and snakes, and none were blind. It was difficult to puzzle out, but the blind fish gave them a place to start.

    Scientists knew that some fish that lived in deep, underground caves with no light sources often lost their eyesight. So when blind fish rained down on Honduras, scientists began to connect some dots. Clearly, these particular fish were pulled from an underground water source by force.

    It has rained fish on every continent, and each time, people have tried in various ways to explain this strange phenomenon. Historically, villagers thought the “fishes from the heavens” might be answers to prayers for food.  Others suggested that floods overran river banks and oceans, leaving the fish on the city streets. No scientist had actually seen the rain as it occurred, only the fish left on the ground. But in 1990, a National Geographic team happened to be in Honduras when the Rain of Fishes began. They recorded what was happening and made history by finally proving that the fish really did fall from the sky.

    This huge breakthrough wasn't just a spot of good luck. It changed thousands of years of myths and legends into true stories and provided scientific explanations for how fish came to live in deep caves. It explained ancient cave paintings and shed new light on how species have spread over time. It turned out to be a lot more than just a little fishy weather.

    When it comes to learning a foreign language, many people wonder if they will be able to memorize enough vocabulary. But this question never happens about their mother tongue, and yet, it was a foreign language once. However, among all the questions that new parents ask, no doctor has ever heard: "Will my baby be able to learn my language?" Be honest, do you know all the words of your mother tongue? The answer is: "no".

    New words, and new ways of using old words, appear every day. Twenty years ago, who could have been able to understand a sentence like this: "Click here to download your digital book."? Nobody. You never stop learning new vocabulary and you never know how long you will need it.

    Sometimes, you have the word on the tip of your tongue...and it sticks there! But you do know this phenomenon(现象) and don't think that it is because of a bad memory. You should not give this phenomenon more importance in the language you are learning than in your mother tongue.

    You need to learn only 2000 or so basic words to be able to create any phrase you need. You can't avoid some work in order to learn these necessary words and all the more if you want to learn quickly. And before you consider buying into any method, be sure it is right for you. It is not wise to depend on any method based upon mnemonics(记忆群). The first few words seem very easy to learn, so you buy the course, but then you discover quickly, though too late, that a dozen words later, it is all the more difficult to learn a new word when you have also to learn the trick to memorize it.