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    Women who own cats are more likely to have mental health problems and kill themselves because they can be infected by a common parasite that can be caught from cat litter, a study has found.

    Researchers found women infected with the Toxoplasma gondii (T. gondii) parasite(刚地弓形虫), which is spread through contact with cat waste or eating undercooked meat or unwashed vegetables, are at increased risk of attempting suicide.

    The study involved more than 45,000 women in Denmark. About a third of the world's population is infected with the parasite, which hides in cells in the brain and muscles, often without producing symptoms.

    The infection, which is called toxoplasmosis(弓形虫病), has been linked to mental illness, such as schizophrenia(精神分裂症), and changes in behavior.

    The study's senior author Doctor Teodor Postolache, an associate professor of psychiatry(精神病学) at the University of Maryland School of Medicine in the United States, said, “We can't say with certainty that T. gondii caused the women to try to kill themselves, but we did find a predictive association between the infection and suicide attempts later in life that deserves additional studies.”

    Doctor Albert Reece, vice president of medical affairs at the University of Maryland, said, “T. gondii infection is a major public health problem around the world, and many people don't realize they're infected.

    “Dr Postolache is a leading expert on suicide neuroimmunology(神经免疫学). Suicide is a critically important mental health issue. About one million people commit suicide and another 10 million attempt suicide worldwide each year. We hope that this type of research will one day help us find ways to save many lives that now end too early in suicide.”

    Dr. Postolache's research team at the University of Maryland was the first to report a connection between T. gondii and suicidal behavior in 2009. He is cooperating with researchers in Denmark, Germany and Sweden to confirm and investigate the way leading to this association.

    The T. gondii parasite thrives in the intestines of cats, and it is spread through their waste. All warm-blooded animals can become infected through contact with it. Humans can become infected by changing their infected cats' litter boxes, eating unwashed vegetables, drinking water from a polluted source, or by eating undercooked or raw meat.

    Not washing kitchen knives after preparing raw meat before handling another food item also can lead to infection. Pregnant women can pass the parasite directly to their unborn babies and are advised not to change cat litter boxes to avoid possible infection.

    Babies don't produce antibodies to T. gondii for three months after they are born, so the antibodies present in their blood represented infection in the mothers. The scientists studied Danish health patients to determine if any of these women later attempted suicide, including cases of violent suicide attempts which may have involved guns, sharp instruments and jumping from high places.

    The study found that women infected with T. gondii were one and a half times more likely to attempt suicide compared to those who were not infected, and the risk seemed to rise with increasing levels of the T. gondii antibodies.

    Dr Postolache noted limitations to the study, such as the inability to determine the cause of the suicidal behavior.

    The findings were published online in the Archives of General Psychiatry.

The baby monkey is much more developed at birth than the human baby. Almost from the moment it is born, the baby monkey can move around and hold tightly to its mother. During the first few days of its life the baby will approach and hold onto almost any large, warm, and soft object in its environment, particularly if that object also gives it milk. After a week or so, however, the baby monkey begins to avoid newcomers and focuses its attentions on “mother” — the real mother or the mother-substitute(母亲替代物）.

During the first two weeks of its warmth is perhaps the most important psychological（心理的） thing that a monkey mother has to give to its baby. The Harlows, a couple who are both psychologists, discovered this fact by offering baby monkeys a choice of two types of mother-substitutes — one covered with cloth and one made of bare wire. If the two artificial mothers were both the same temperature, the little monkeys always preferred the cloth mother. However, if the wire model was heated, while the cloth model was cool, for the first two weeks after birth the baby monkeys picked the warm wire mother-substitutes as their favorites. Thereafter they switched and spent most of their time on the more comfortable cloth mother

    Why is cloth preferable to bare wire? Something that the Harlows called contact（接触的） comfort seems to be the answer, and a most powerful influence it is. Baby monkeys spend much of their time rubbing against their mothers' skins, putting themselves in as close contact with the parent as they can. Whenever the young animal is frightened, disturbed, or annoyed, it typically rushes to its mother and rubs itself against her body. Wire doesn't“rub”as well as does soft wire cloth. Prolonged（长时间的）“contact comfort” with a cloth mother appears to give the babies confidence and is much more rewarding to them than is either warmth or milk.

    According to the Harlows, the basic quality of a baby's love for its mother is trust. If the baby is put into an unfamiliar playroom without its mother, the baby ignores the toys no matter how interesting they might be. It screams in terror and curls up into a fury little ball. If its cloth mother is now introduced into the playroom, the bay rushes to it and holds onto it for dear life. After a few minutes of contact comfort, it obviously begins to feel more secure. It then climbs down from the mother-substitute and begins to explore the toys, but often rushes back for a deep embrace（拥抱）as if to make sure that its mother is still there and that all is well. Bit by bit its fears of the new environment are gone and it spends more and more time playing with the toys and less and less time holding on to its “mother.”

    If someone asked you to quantify (衡量) the time you spend online, how would you answer? If you're like one-fifth of Americans, you'd likely say “almost constantly.” New research shows that 21 percent of Americans report that they're online more or less constantly.

    Andrew Perrin, a research assistant at Pew, did a survey about Internet use. During the survey, adults were asked how much they go online. 13 percent said they don't go online and 13 percent said they go online several times a week or less. Only 10 percent said they go online once a day and much larger quantities said they go online several times a day (42 percent) or “almost constantly” (21 percent).

    Interestingly, there wasn't a gender split (性别分化) when it came to near constant Internet use. Age seems to be the great divider: Only six percent of people over 65 said they were online that much. Those who reported that they were online all the time included 12 percent of 50- to 64-year-olds, 28 percent of 30- to 49-year-olds and 36 percent of 18- to 29-year-olds.

    Don't suppose that teenagers are online more than adults, however. In another survey, Pew found that while they did have a slight edge on adults in general when it came to “almost constant” Internet use, 24 percent said they were online pretty much all the time. They still fell greatly behind the 36 percent of adults between 18 and 29 years of age who were always online.

    Given that the United Nations considers unrestricted (无限制的) Internet access (接入) to be a human right, the number of Americans who report being online “almost constantly” could rise along with availability and affordability. But it remains to be seen whether being online all the time is actually something to long for, or how constant connectivity will affect American culture in the long term.

    You are going to read three competitions which offer holidays as prizes.

    Competition One

    Competition Two

    Competition Three

    In the future we might live somewhere other than Earth, like Mars. Some people ask how this will be possible. Well, Mars is in fact a lot the same as the earth. The days are almost the same as those on the earth. However, the two planets vary in temperature.

    Since there is mostly carbon dioxide on Mars, it would be quite difficult for a human to just land on it. So, special types of homes and space suits have to be designed. The space suits should be almost like the ones astronauts use now, and except that they have to be warmer so that the astronauts can survive the cold temperatures. The space suits must also be able to withstand (承受) high pressure and potentially dangerous radiation that can kill.

    The houses should be similar to our homes today with a slight difference. All of the houses and other buildings should be built inside a large dome (圆顶状物) or bubble. The domes should be made out of glass, and would also be able to prevent radiation from affecting the people inside. The domes will be connected to a machine (like plants which turn carbon dioxide into oxygen).

    With Mars' population growing, how would the people on its surface get fresh food and water? Just like humans use domes, they can also use domes to grow plants. However, the domes where the plants are grown must be built to expand. Once we upgrade the domes to a larger size then we can grow more food by cultivating (种植) more plants. To get the food or come in connect with other domes, there will be long narrow tunnels like roads that connect to each dome separating them by several doors so that the pressure in each dome can remain the same.

    On Mars, so many other things are available to us. As humans, we can have access to rare and fairly expensive metals that aren't very easy to get hold of on Earth, and a colony on Mars enhances (提高) our chances of finding these metals. So when someone here on Earth says that going to Mars is impossible, please tell them that they'll never know it until they try and they may try very soon. After all it's our future. Why not make it on Mars?

As people are becoming more socially conscious about where their food comes from and how it impacts the planet, they are choosing animal-free plant-based options. Cow-free meat has been around for quite some time and the popularity of brands of the cultivated meat is rising. While there are a large number of plant-based milk substitutes, none of them have the same taste of cow's milk. Now, a food-tech company created real dairy products without harming a single cow or the planet.

The company stresses that their product produced in the lab is not a milk substitute but rather is the real deal. And it is very healthy. The company also says that the lab-produced milk tastes identical to the real thing and they hope to eventually replace cows by creating every dairy product sold. They expect to roll out plant-based cheese and yogurt in addition to milk. “Our company was founded with the mission to stop using animals to produce -our food because, as dairy lovers, we realize that giving up on milk is not an option,” John said. “But today's milk comes with an unreasonable price tag. The dairy industry is destructive to our planet, our health, and our animals, and is simply not sustainable anymore.”

The environmental price tag of dairy farming is way too high. According to the World Wildlife Fund, dairy cows add a huge amount of greenhouse gases to the atmosphere and-contribute to global warming and climate change as well as pollute the air around them. Dairy operations consume large amounts of water and run-off of manure and fertilizers from these farms get into local waterways. The production uses only 5 percent of the resources and produces only 1 percent of the waste of producing cow's milk according to the company. And they accomplish this by being 100 percent cruelty-free unlike dairy farms.