Cancer is a leading cause of death around the world.

    When it comes to cancer, the sooner you know you have it, the better your chances of surviving are.

    A new blood test could change the way doctors and researchers find cancer in patients. Researchers say the test could provide some hints of the early forms of the disease.

    Gareth Jenkins is a professor at the University of Swansea. He says he and his team did not look for cancer. They instead looked for a by-product of cancer, mutated (突变的) red blood cells. They looked for, what Jenkins calls, the collateral (附带的) damage of cancer—the damage left by the disease.

    “In this blood test we don't measure the presence of cancer，we measure the presence of mutated red blood cells which are the collateral damage that occurs—a by-product of the cancer developing.''

    The researchers used normal laboratory equipment to perform the tests. This equipment looks for changes in the structure of millions of red blood cells. Those mutated cells lack a surface protein (蛋白质) that healthy cells normally have.

    “The goal of the test is looking for very rare cells which have picked up a mutation. The number of mutated red blood cells in a healthy person is around 5 or so mutated cells per million; so, you have to look at millions of red blood cells to discover those rare events. The number increases in cancer patients—it goes up to 40 or 50 on average.”

    The researchers tested blood from about 300 people, all of whom have cancer of the esophagus (食管). Patients with esophageal cancer have high levels of mutated red blood cells. Jenkins says that at this point he is not sure if other cancers would produce similar results.

    The hope is that the new test could one day become part of commonly used medical methods to find out if a person has cancer. These new technologies could save millions of lives.

    Why do human beings still risk their lives under ground and doing one of the dirtiest and most dangerous jobs in the world? It is an increasingly urgent question, given the recent mining accidents in Sago, W. Va and Huntington, Utah. A small group of engineers and robotics experts look forward to a day in the not-too-distant future when robots and other technology do most of the dangerous mining work.

    Robotic technology, in particular, holds much promise, McAteer says, especially when it comes to mapping mines and rescuing trapped miners — the special operations of the mining industry.

    One of the first mining robots was developed five years ago at Carnegie Mellon University's Robotics Institute. It was called Groundhog. It used lasers(激光器) to “see” in dark tunnels and map abandoned mines—some of the most dangerous work in the business.

    The latest design is called Cave Crawler. It's a bit smaller than Groundhog, and even more advanced. It can take photos and videos and has more sensors that can detect the presence of dangerous gases. Incredibly, the robot has a real sense of logic. If it comes across an obstacle it gets momentarily confused. It has to think about what to do and where to go next. Sometimes it throws a fit just like a real person.

    The greatest problem, though, is cost. The money of the earliest research project was provided by the government, but that money had dried up, and it's not clear where future money will come from. Partly for that reason, and partly because of advances in safety, mining is not nearly as dangerous as it was in the past. Since 1990, fatalities(致命性) have declined by 67% and injuries by 51% , according to the National Mining Association.

    Some experts predict that robots in mines will serve much of the same function that they do in the automotive industry. The robots do the most boring and dangerous jobs，but won't get rid of the need for human workers.

阅读下列短文，从每题所给的四个选项（A、B、C和D）中，选出最佳选项。

    In the tenth grade，I began working for free at a vet's that was run by a friend. I wanted to get experience for what I thought would be my future job. However，on one particular Saturday morning I learnt something perhaps more important.

    The hospital was in the middle of one of the poorer sections of the city and some people could only pay for the most basic treatments. On this Saturday，a man and his young son，who was probably about 7 years old，walked in with a small cat in a cardboard box. There was something wrong with the cat's left eye. But the man could not afford to pay for the cost of the medicine. He kept quiet for a while，and then he asked where the nearest animal shelter was. Hearing this，his son cried and started to argue with him. All of a sudden，an older woman who was sitting in the waiting room stood up，walked up to the counter，and told the man that she would pay for the cost. The man thanked her and the son got to keep a healthy cat.

    I always thought it was the right thing to help out a needy person，but I only saw people do acts of kindness on TV or in movies. What the woman did made me believe that these things do happen in real life，and quite often.

Now，when I can't decide whether to help someone who is in need，I remember this woman，and then I have the courage to step up to the plate. Sometimes other people follow.

    Dearborn Heights,Michigan—2.7 million children under 18 have a parent in prison,and women put in local prisons are the fastest growing population.Shawna Reynolds has seen some of those women up close while working in the corrections system(劳教所) for 17 years,and she was encouraged to try something different.

    After seven years of education and collecting as much money as she could,Shawna created About Face Course Correction-a one-year rehabilitation program(康复项目) that offers a more personal way to help non-violent women prisoners.The program includes classes for women to finish their education, find a job and So on.“You can't expect people who have been in prison to stay in prison,”Shawna says.“YOU want them to be helpful people but if you are not going to help them, it's not going to happen.”

    The women live free for a year in a house in Dearborn Heights, Michigan.Women like 20-year-old Jennifer Douglas, who dropped out of school,took drugs (吸毒)，and has spent years in and out of prison. She says,“I was doing things I would never have thought I would do in my whole life.Because of About Face, Jennifer's life is changing. “Everyone is starting to trust me again and proud of me and what I'm doing,” she says. “ It's helped me a lot.It has kept me on the right track.”

    There are many other women like Jennifer. Every woman's story is different,but each woman is important.And Shawna is determined to break the cycle and help them turn their lives around.She is using her own money and donations to pay for the house and this program.If you would like to donate, please visit their Go Fund Me account here.

    Twenty-five years ago, as a parent educator, I began reading about the dangers of praise. I was completely shocked by what I was learning: praise is not good for our kids. How could that be? So I spent years talking with experts, reading about the effects of praise, and finally decided to close the door on praise and focus on building an encouraging family.

    Even today, with many studies available to parents, I still hear people say, "How can that be? How can saying 'Good job' or 'You're smart' be bad?" I understand. It can be a difficult habit to break.

    If we tell a boy "You are so smart!" when he brings home an A in his math test, how does he feel when he comes home with a D? If we've told him that he is smart, then he will more likely feel a failure when he struggles with homework — "I'm supposed to be smart. Why can't I do this?"

    Praise trains children to depend on constant feedback on what a "great job" they are doing. This dependency shatters rather than builds children's confidence. Praise trains children to ask, "Do you like it?" "Did I do a good job?" "Are you proud of me?" They begin to believe that what others think is more important than what they think about their achievements and mistakes.

    Praise breaks the relationship between parents and children. Without even realizing it, parents may be using praise as a tool to direct the child's behavior. The message is clear — I approve of you when you … and I do not approve of you when you … Living with this kind of constant judgment can damage not only the child's confidence but also the relationship.

    The solution to the problem of praise is encouragement. Encouragement can be given at any time, to anyone, in any situation. It is a comment, an acknowledgment, a statement that focuses on effort, improvement or choice. Hearing "You are so smart!" can leave a child at a loss when they don't do well in a test. Using "That took a lot of work to come home with an A in your test …" gives a child the chance to be something else.

    Does the amount of cash in a lost wallet influence how likely a person is to return it? Classical economic theories suggest that the greater the appeal, the less likely we are to be honest—but a new study turns the idea on its head, finding altruism(利他主义), and a powerful hate for viewing oneself as a "thief" outweigh the financial attraction.

    A team of researchers conducted a huge experiment concerning 355 cities in 40 countries. More than 17,000 identical wallets were dropped off at public places, each containing a grocery list, a key, and three business cards in the local language using made-up names and an email address. Some had no money while others contained the equivalent (等值) of $13.45.

    According to the research, people on average returned 40% of wallets with no money in them but 51%with money. It also shows extreme differences between countries. But although rates of people's honesty varied greatly from country to country, one thing remained remarkably constant: wallets with money, as opposed to no money, raised reporting rates.

    In the US, the UK and Poland, they repeated the experiment with even more money: $94.15, which increased reporting rates by an average of 11% compared to the smaller amount. They also found that having a key expanded reporting rates by 9.2%.

    The findings, which run counter to a fundamental principle of classical economics, suggest honesty, altruism and self-image can sometimes be more influential than economic self-interest.

    A purely economic approach to behavior suggests people would keep the wallets with the larger amounts of money due to the increased financial reward, but economics often doesn't account for a person's sense of honesty or self-image, according to behavioral scientists. Altruism also influenced the findings, the researchers say. Since the key is valuable to the owner but not the finder, this pointed toward an altruism concern in addition to the cost of negatively updating one's self image.