Irradiating (照射) fruits, vegetables, pork and chicken to kill insects and bacteria has been approved by the Food and Drug Administration over the past decade or so. Irradiation of other meats, such as beef and lamb, is being reviewed. Federal approval does not require that industry adopt the process, and few food processors presently offer irradiated products. Market studies have shown that many consumers are afraid that eating irradiated foods may cause cancer, despite scientific studies that prove the safety of treated foods. Some people argue that more severe government inspection, higher food-safety standards, and more careful food-preparation practices by consumers are all that is needed to ensure that food is safe. Consequently, companies currently see no need to spend millions of dollars outfitting (配备) processing plants with the equipment necessary for a process that very few shoppers are in favor of. All supermarkets that sell irradiated food must label that food either directly on the packaging or in the case of bulk items like fruits and vegetables by placing a sign nearby. There is no requirement for the labeling of irradiated food served by chain restaurants or hospitals that buy directly from distributors, nor any regulations for products that contain irradiated ingredients. Presently, the FDA allows food to be treated with three types of radiation—gamma rays, high-energy electrons, and X-rays—and sets limits on doses (辐射量) depending on the type of food. The principle is that the dose to be used for a certain type of food should not exceed the amount that is sufficient to kill most harmful insects and bacteria present in it. Different types of food, because of their different molecular (分子) compositions, may require different doses of radiation.

In times of economic crisis, Americans turn to their families for support. If the Great Depression is any guide, we may see a drop in our skyhigh divorce rate. But this won't necessarily represent an increase in happy marriages. In the long run, the Depression weakened American families, and the current crisis will probably do the same. We tend to think of the Depression as a time when families pulled together to survive huge job losses. By 1932, when nearly one-quarter of the workforce was unemployed, the divorce rate had declined by around 25% from 1929. But this doesn't mean people were suddenly happier with their marriages. Rather, with incomes decreasing and insecure jobs, unhappy couples often couldn't afford to divorce. They feared neither spouse could manage alone. Today, given the job losses of the past year, fewer unhappy couples will risk starting separate households. Furthermore, the housing market meltdown will make it more difficult for them to finance their separations by selling their homes. After financial disasters family members also tend to do whatever they can to help each other and their communities. A 1940 book, The Unemployed Man and His Family, described a family in which the husband initially reacted to losing his job "with tireless search for work." He was always active, looking for odd jobs to do. The problem is that such an impulse is hard to sustain. Across the country, many similar families were unable to maintain the initial boost in morale (士气). For some, the hardships of life without steady work eventually overwhelmed their attempts to keep their families together. The divorce rate rose again during the rest of the decade as the recovery took hold. Millions of American families may now be in the initial stage of their responses to the current crisis, working together and supporting one another through the early months of unemployment. Today's economic crisis could well generate a similar number of couples whose relationships have been irreparably (无法弥补地) ruined. So it's only when the economy is healthy again that we'll begin to see just how many broken families have been created.

People are being lured (引诱) onto Facebook with the promise of a fun, free service, without realizing they're paying for it by giving up loads of personal information. Facebook then attempts to make money by selling their data to advertisers that want to send targeted messages. Most Facebook users don't realize this is happening. Even if they know what the company is up to, they still have no idea what they're paying for Facebook, because people don't really know what their personal data is worth. The biggest problem, however, is that the company keeps changing the rules. Early on, you could keep everything private. That was the great thing about Facebook—you could create your own little private network. Last year, the company changed its privacy rules so that many things—your city, your photo, your friends' names—were set, by default (默认), to be shared with everyone on the Internet. According to Facebook's vice-president Elliot Schrage, the company is simply making changes to improve its service, and if people don't share information, they have a "less satisfying experience." Some critics think this is more about Facebook looking to make more money. Its original business model, which involved selling ads and putting them at the side of the page, totally failed. Who wants to look at ads when they're online connecting with their friends? The privacy issue has already landed Facebook in hot water in Washington. In April, Senator Charles Schumer called on Facebook to change its privacy policy. He also urged the Federal Trade Commission to set guidelines for social-networking sites. "I think the senator rightly communicated that we had not been clear about what the new products were and how people could choose to use them or not to use them," Schrage admits. I suspect that whatever Facebook has done so far to invade our privacy, it's only the beginning. Which is why I'm considering deactivating (撤销) my account. Facebook is a handy site, but I'm upset by the idea that my information is in the hands of people I don't trust. That's too high a price to pay.

As you are probably aware, the latest job markets news isn't good: Unemployment is still more than 9 percent, and new job growth has fallen close to zero. That's bad for the economy, of course. And it may be especially discouraging if you happen to be looking for a job or hoping to change careers right now. But it actually shouldn't matter to you nearly as much as you think. That's because job growth numbers don't matter to job hunters as much as job turnover (人员更替) data After all, existing jobs open up every day due to promotions, resignations, terminations (解雇), and retirements. (Yes, people are retiring even in this economy.) In both good times and bad, turnover creates more openings than economic growth does. Even in June of 2007, when the economy was still moving ahead, job growth was only 132,000, while turnover was 4.7 million! And as it turns out, even today—with job growth near zero—over 4 million job hunters are being hired every month. I don't mean to imply that overall job growth doesn't have an impact on one's ability to land a job. It's true that if total employment were higher, it would mean more jobs for all of us to choose from (and compete for). And it's true that there are currently more people applying for each available job opening, regardless of whether it's a new one or not. But what often distinguishes those who land jobs from those who don't is their ability to stay motivated. They're willing to do the hard work of identifying their valuable skills; be creative about where and how to look; learn how to present themselves to potential employers; and keep going, even after repeated rejections. The Bureau of Labor Statistics data shows that 2.7 million people who wanted and were available for work hadn't looked within the last four weeks and were no longer even classified as unemployed. So don't let the headlines fool you into giving up. Four million people get hired every month in the U.S. You can be one of them.

Our risk of cancer rises dramatically as we age. So it makes sense that the elderly should be routinely screened for new tumors—or doesn't it? While such vigilant (警觉的) tracking of cancer is a good thing in general, researchers are increasingly questioning whether all of this testing is necessary for the elderly. With the percentage of people over age 65 expected to nearly double by 2050, it's important to weigh the health benefits of screening against the risks and costs of routine testing. In many cases, screening can lead to surgeries to remove cancer, while the cancers themselves may be slow-growing and may not pose serious health problems in patients' remaining years. But the message that everyone must screen for cancer has become so deep-rooted that when health care experts recommended that women under 50 and over 74 stop screening for breast cancer, it caused a riotous reaction among doctors, patients and advocacy groups. It's hard to uproot deeply held beliefs about cancer screening with scientific data. Certainly, there are people over age 75 who have had cancers detected by routine screening, and gained several extra years of life because of treatment. And clearly, people over age 75 who have other risk factors for cancer, such as a family history or prior personal experience with the disease, should continue to get screened regularly. But for the remainder, the risk of cancer, while increased at the end of life, must be balanced with other factors like remaining life expectancy (预期寿命). A recent study suggests that doctors start to make more objective decisions about who will truly benefit from screening—especially considering the explosion of the elderly that will soon swell our population. It's not an easy calculation to make, but one that makes sense for all the patients. Dr. Otis Brawley said, "Many doctors are ordering screening tests purely to cover themselves. We need to think about the rational use of health care." That means making some difficult decisions with elderly patients, and going against the misguided belief that when it comes to health care, more is always better.