【推荐1】Water poisoning is caused by too much consumption of water during a short period of time. Water in and of itself is not poisonous by any means, but rapid intake of a large quantity of water can break the careful balance of sodium(钠)in the body fluids(体液). This contributes to a swelling of the cells, often in the central nervous system, including the brain.

When the cells can no longer bear the pressure, they can begin to die. This is indicated in serious forms of water poisoning. Symptoms of this condition include vomiting, headache and unresponsiveness. When the sodium in the blood falls to dangerous levels, brain damage and possibly death may occur.

What is a fatal(致命的)amount of water can vary from person to person, depending on one’s state of health, his or her physical activity at the time, the temperature and the amount of time in which the person consumes the water. For some, a one-time consumption of three liters can prove deadly. Although the person consuming the water may lose a lot of fluid during heavy labor or exercise, the electrolytes(电解质)are not replaced fast enough to avoid water poisoning.

Those particularly at risk for water poisoning are athletes engaged in long distance running like a marathon. Due to the need to replace large quantities of lost fluid, runners must drink a lot of water. This can lead to poisoning, so runners must replace their fluids with sports drinks that have added electrolytes. Other factors that contribute to water poisoning include activities that stimulate heavy sweating. The person working under extreme heat or intense humidity(湿气)must be careful when consuming water in order to maintain electrolyte balance. Mental diseases can also lead to water poisoning. Psychogenic polydipsia is a condition in which the affected person feels a need to drink a lot of water for unknown reasons.

【推荐2】It is a practice favored by Lena Dunham, Tom Hanks and Lady Gaga to improve their focus and bring about calmness in an often busy, distracted world. Now researchers have found evidence that frequent meditation (冥想) over several years, may help change human gut (肠道), boost the body’s immune (免疫的) system and reduce the risk of anxiety, depression and heart disease. The findings are published by the British Medical Journal.

Meditation is increasingly used to help treat drug abuse, overwhelming stress, eating disorders and long-lasting pain. But until now it has not been clear whether it could also be able to change the composition of the gut microbiome (微生物组). In an effort to find out, researchers led by the Shanghai Mental Health Centre at the Shanghai Jiao Tong University analyzed the stool (粪便) and blood samples of 37 Tibetan Buddhist monks from three temples and 19 residents in the neighboring areas. The Tibetan meditation from the ancient Indian medical system, is a form of psychological training. The monks in the study had practiced it for at least 2 hours a day for 3-30 years. Both groups were matched for age, blood pressure, heart rate and diet. Stool sample analysis revealed significant differences in the diversity and volume of microbes between the monks and their neighbors. “Bacteria enriched in the meditation group had a positive effect on human physical and mental health,” the researchers wrote. “This changed gut microbiome composition could improve immune function in the body.” Blood sample analysis also revealed the levels of markers associated with risk of heart disease were significantly lower in the monks.

The researchers emphasized that the study was observational and the number joining was small, all male and living at high altitude, making it difficult to draw any firm or general conclusions. However, based on their findings, the researchers said the role of meditation in helping to prevent or treat mental and physical illness deserved further research.

【推荐3】If you ever get the impression that your dog can “tell” whether you look content or annoyed, you may be onto something. Dogs may indeed be able to distinguish between happy and angry human faces, according to a new study.

Researchers trained a group of 11 dogs to distinguish between images (图像) of the same person making either a happy or an angry face. During the training stage, each dog was shown only the upper half or the lower half of the person’s face. The researchers then tested the dogs’ ability to distinguish between human facial expressions by showing them the other half of the person’s face on images totally different from the ones used in training. The researchers found that the dogs were able to pick the angry or happy face by touching a picture of it with their noses more often than one would expect by random chance.

The study showed the animals had figured out how to apply what they learned about human faces during training to new faces in the testing stage. “We can rule out that the dogs simply distinguish between the pictures based on a simple cue, such as the sight of teeth,” said study author Corsin Muller. “Instead, our results suggest that the successful dogs realized that a smiling mouth means the same thing as smiling eyes, and the same rule applies to an angry mouth having the same meaning as angry eyes.”

“With our study, we think we can now confidently conclude that at least some dogs can distinguish human facial expressions,” Muller told Live Science.

At this point, it is not clear why dogs seem to be equipped with the ability to recognize different facial expressions in humans. “To us, the most likely explanation appears to be that the basis lies in their living with humans, which gives them a lot of exposure to human facial expressions, and this exposure has provided them with many chances to learn to distinguish between them,” Muller said.

【推荐2】“Don’t be a victim.” That’s a phrase you’ll hear a lot if you take a crime-prevention class. Basically, it means that there are steps you can take to reduce the likelihood that you’ll be mugged, assaulted, or otherwise attacked. Don’t wave your cash around like you’re a billionaire. Don’t be distracted on the subway. Walk with a purpose.

That last one is particularly important, because according to a new study from the Journal of Interpersonal Violence, some criminals are very good at sensing weakness based on the way you walk. Actually, serial killer Ted Bundy admitted in a personal interview in 1985 that “he could tell a victim by the way she walked down the street, the tilt of her head, the manner in which she carried herself, etc…” Unfortunately, research demonstrated the reality that criminals do in fact look for, or at least notice certain characters when selecting potential victims. While nothing excuses crime, knowledge is power in the sense that there are things we can do to protect ourselves when we are out alone.

In the report titled “Psychopathy and Victim Selection” the researchers surveyed 47 criminals at a maximum-security prison in Ontario and found that social predators are very good at picking victims based on their posture and gait(步伐). They noted that people might be releasing vulnerability to criminals through their postures, gestures, and exaggerated movements.

The researchers secretly filmed 12 people walking — eight women and four men, some of whom had been attacked before. Then, they showed the video to a group of criminals and asked them whether or not each person would make a good victim. These “victim ratings” were then compared against each person’s actual history of victimization. Sure enough, the people whom the criminals picked as “likely victims” were usually the ones who had been victimized in the past. These people were often said to have “walked like an easy target” — slowly, unfocused, with short steps.

The sample size here is really small. Maybe we shouldn’t give this study’s findings too much weight. Nevertheless, it emphasizes something that seems pretty unconscious. Criminals aren’t looking for a challenge. Rather, they want someone timid and inattentive. So stride down the street like you own it. Your new, aggressive gait may scare off criminals. And even if this study turns out to be total bullshit, you’ll still get where you’re going a lot faster.