Have you ever wondered when dogs first became “man's best friend” and the world's favourite pet? If you have then you're not alone. When and where dogs first began living side-side with humans are questions that have stirred hot debate among scientists. There are a few hard facts that all agree on. These include that dogs were once wolves and they were the first animal to be domesticated(驯养) by humans. They came into lives some 15000 years ago, before the dawn of agriculture.

    Beyond that, there is little agreement. The earliest bones found that are unquestionable dogs and not wolves date from 14,000 years ago. However, 30,000-year-old skulls have been discovered in France and Belgium that are not pure wolf and some scientists think could be dogs.

    With such puzzling evidence, many scientists are now turning to DNA to find out when and where dogs were first domesticated. In one research project, tens of thousands of blood samples have been taken from street dogs around the world. The plan is to compare them with those of wolves. It's even possible to analyse DNA from ancient bones. Tiny pieces of the 30,000-year-old skulls mentioned earlier are currently being studied, and another DNA study has already shown that ancient dogs preserved in the Alaskan ice-fields evolved from Asian wolves, not American ones.

    Indeed, the ancient DNA may turn out to be more informative than the DNA of living dogs. Because dogs have accompanied humans around the world for thousands of years, their current distribution may tell us very little of their origins. This is why different groups of scientists believe that dogs variously originated in eastern Asia, Mongolia, Siberia, Europe or Africa.

    But why were the animals domesticated in the first place? The most recent theory is that dogs domesticated themselves, initially living in and around our ancient villages to eat any food thrown out. Today, this is a way of life still shared by three -quarters of a billion unowned dogs worldwide.

    In a natural disaster: a hurricane, flood, volcanic eruption, or other catastrophes. Minutes and even seconds of warning can make the difference between life and death. Because of this, scientists are working to use the latest technological advances to predict when and where disasters will happen. They are also studying how best to analyze and communicate this information once it is obtained.

    On September 29,1998, Hurricane Georges made landfall in Biloxi, Mississippi, after damaging Haiti, the Dominican Republic, Puerto Rico, and several islands of the Caribbean badly with heavy rains and winds up to 160 km per hour. Few people lost their lives along the Gulf Coast of the United States, although hundreds died in the Caribbean. This was a very different result, when a powerful Gulf Coast hurricane made an unexpected direct hit on Galveston, Texas, killing at least 6,000 people. Vastly improved hurricane warnings explain the different circumstances at either end of the 20th century—residents of Galveston had no advance warning that a storm was approaching, while residents of Biloxi had been warned days in advance, allowing for extensive safety precautions (预防).

    At the same time that people in Biloxi were thankful for the advance warning, some residents of New Orleans, Louisiana were less satisfied. A day before Georges made landfall, forecasters were predicting that the hurricane had a good chance of striking New Orleans. Emergency management officials must begin evacuations (疏散) well before a storm strikes. But evacuation costs money. The mayor of New Orleans estimated that his city's preparations for Georges cost more than 50 million. After Georges missed New Orleans, some residents questioned the value of the hurricane forecasts in the face of such high costs.

    The different views on the early warnings for Hurricane Georges show some of the complexities (复杂) related to predicting disasters. Disaster prediction is a process of providing scientific information to the government officials and other decision makers who must respond to those predictions.

    Mary bought a dress in a women's clothing store.She felt very happy about buying the dress until she got home. Then she remembered she had left her purse at the store.It was the third time that month that Mary had forgotten something important.Mary was angry with herself.She said,“Am I losing it?”

    Emma was teaching a class in mathematics at a college.She began to explain to the students how to solve a very difficult problem.She understood it very well.But somehow,at that moment,she could not explain it.Emma said,“I must be losing it.”

    Americans seem to have a lot of concern about losing it.At least that is what you would think from hearing them talk.They use the expression when they feel they are losing control.It can mean losing emotional control.Or losing the ability to do something.Or losing intelligence.

    Word experts differ about how the expression started.Some believe it came from television programs popular in the 1980s.Others believe it began with psychologists,who deal with how people think,feel and act.

    “We Americans have many concerns about controlling our lives.Perhaps we worry too much,”one psychologist said.“In many situations to say you are losing it eases the tension（不安）.”

    It's healthy.And most people who say they are having a problem are not losing it.

    People may feel more like they are losing it when they are “down in the dumps”.Word expert Charles Funk says people have been feeling down in the dumps for more than 400 years.The word dumps probably comes from Northern European countries.The languages of Denmark and Norway both have similar words.The words mean to fall suddenly.Americans borrowed this saying.And,over the years,it has become a popular way of expressing sadness.

    If you want to convince the boss you deserve a pay rise or promotion, the solution could be simple — eat the same food as they do. Psychologists have discovered managers are much more likely to instantly trust us if we choose the same dishes as them.

    During experiments, discussions over wages and work conditions were much more successful if both sides chose to snack on the same treats. And shoppers were much more likely to buy a product advertised on TV by someone eating a similar food to them at the time.

    The reason is thought to be so-called similarity attraction theory — where people tend to like others who have similar tastes or habits to themselves. But this is believed to be one of the first studies highlighting the role of food in this relationship. Researchers at Chicago University in the US conducted a series of experiments to examine food's role in earning trust.

    In a test, participants were told to watch TV — where someone pretending to be a member of the public praised a certain product. The volunteers were given Kit Kat bars to nibble (咬), while the TV people ate either a Kit Kat or grapes as they talked.

    The results showed viewers were much more likely to express an interest in buying the product if the TV showed the other person eating a Kit Kat too.

    The researchers added, “Although similarity in food consumption is not a sign of whether two people will get along, we find consumers treat this as such. They feel more trusting of those who consume as they do. It means people can immediately begin to feel friendship and develop a bond, leading to smoother transactions (交易) from the start.”

    Harley Street psychologist Dr. Lucy Atcheson said it was already known that wearing similar clothes could instantly create trust. But this was the first report that food had the same effect. She said, “This is really interesting. It makes sense as people feel they have common ground and can trust the other person. That means negotiations are more likely to be successful.”

    About aspirin (阿司匹林):

    Aspirin is a commonly used drug which can be taken to relieve discomfort caused by numerous medical problems including headaches, toothache, inflammation(发炎) and infections. It is also suitable to treat colds and flu-like symptoms(症状), and to reduce a high temperature.

    Who can take aspirin? Adults and children over 16 years of age.

    Who should not take aspirin? Women who are pregnant, or plan to become pregnant. Aspirin may harm your unborn baby.

    Women who are breast-feeding. Aspirin can pass into your breast milk and may harm your baby. People who have any problems with the way the liver works or with the way the kidneys work.

    How to take aspirin: Take aspirin after meals, with a full glass of water or milk.

    The recommended dose (剂量) ranges from two to three tablets at a time. Never take more than 4g 12 tablets) in any 24 -hour period. You must not take these tablets with any other medicine which contains any aspirin or painkiller.

    How to store aspirin: Keep all medicines out of the reach and sight of children.

    Store aspirin in a cool, dry place, away from direct heat and light.

    Do not put aspirin in the bathroom because the dampness there can cause it to lose its effectiveness. Throw away aspirin that smells strongly of vinegar.

    Possible side effects: Feeling sick, increased risk of bleeding, stomach pain, indigestion and heartburn are common. If these effects continue, contact your doctor. Ringing in the ears, difficulty breathing, dizziness, and mental confusion are rare. If these occur, stop taking the drug and contact your doctor for further advice.

    A large scale study has found a link between eating a diet based on organic food and having a reduced risk of cancer. If the new results are confirmed, promoting organic food consumption could be a promising preventative strategy against the disease, a team of researchers from several French institutions said.

    Among the environmental risks for cancer, there are growing concerns about exposure to different types of pesticides（杀虫剂） from farming. The impact of such chemicals on the human body is still not well understood but there are some indications that harmful effects can occur even at low concentrations.

    Meanwhile, pushed by environmental and health concerns, the organic food market continues to grow rapidly. Organic food is produced without the use of synthetic（合成的） fertilizers, pesticides, genetically modified organisms, and the use of veterinary（兽医的） medications.

    "Organic foods are less likely to contain pesticide remains than conventional foods, and studies have shown that an organic diet reduces exposure to certain pesticide," Julia Baudry, lead author of the study from the Centre of Research in Epidemiology and Statistics in France, told Newsweek.

    "In the general population, the primary route of exposure is diet, especially intake of conventionally grown fruits and vegetables. However, few studies have examined the association of organic food consumption with cancer risk."

    For the study, published in the journal JAMA Internal Medicine, a team of researchers examined data on the organic food consumption frequency and dietary intake of 68,946 French adults collected by an ongoing survey which began in 2009. They then followed up on these people at various points in the future.

    Participants reported how often （never, occasionally or most of the time） they consumed 16 types of organic foods including fruits, vegetables, soy﹣based products, dairy products, meat and fish, eggs, grains and legumes, bread and cereals, flour, vegetable oils and condiments, ready﹣to﹣eat meals, coffee, tea, and herbal tea, wine, biscuits, chocolate, sugar and so on.