Gabby Douglas stood beneath the Rio Olympic Arena, still in her Team USA leotard, trying hard to understand how she had become the most unpatriotic athlete in Rio. Tears filled in her eyes. She tried hard to talk but no words came out. Her pauses were long and uncomfortable.

    “I've been trying to stay off the Internet because there's so much negativity,” she said. The attacks against her have been everywhere these last few days. The bullies blamed her for not putting her hand over her heart while the US national song played. Besides, some other people attacked her for not jumping up and cheering hard enough for team-mates at the all-around final. All of this prompted her mother, Natalie Hawkins, to tell Reuters this weekend, that Douglas is “heartbroken”.

    It showed on Sunday, in Douglas's final performance of this Olympics and maybe in the Games ever. Douglas finished sixth in the uneven bars, far from the medal stand she owned four years ago in London, and shook her head, confused. What had she done wrong? Nothing made sense.

    “I mean, you do [Olympics] for your country, and you do it for yourself, how have I offended them? What have I done? I was standing in respect for USA. I'm coming out there representing them to the best of my abilities, so how would I be in disrespect?

    Many studies have shown that the company of pets can help lower blood pressure and raise chances of recovering from a heart attack, reduce loneliness and help control body weight.

    Any pet owner will tell you how much joy a pet brings. For some, an animal provides more comfort than a husband/wife. A 2002 study by Karen Allen of the State University of New York measured stress levels and blood pressure in people (half of them were pet owners) while they performed 5 minutes of mental arithmetic (算术) or held a hand in ice water. People completed the tasks alone, with a husband/wife, a close friend or with a pet. People with pets did it best. Those tested with their animal friends had smaller change in blood pressure and returned most quickly to baseline heart rates. With pets in the room, people also made fewer math mistakes than when doing in front of other companions. It seems that people feel more relaxed around pets, says Allen, who thinks it may be because pets don't judge.

    A study reported last fall suggests that having a pet dog may also have an effect on your body weight. Researchers at Northwestern Memorial Hospital spent a year studying two groups of fat people who were put on a diet-and-exercise program: one group with pet dogs, and the other without. On average，dog owners lost about 11 pounds，or 5% of their body weight; While those without dogs lost about 8 pounds. The pet owners, said researchers, got more exercise overall (mostly with their dogs) and found it worth doing.

    Last Saturday on the way to the mall, two children, a boy and a girl, came running towards me with bottles on their hands, asking if I wanted bottled water. It was a surprising gesture. I was wondering if they were doing fund-raising. I knelt and asked them where their parents were and how much a bottle of water cost. Then two adult women came up to me explaining what the children were doing. “We are teaching the children to give without anything in return. We are teaching people to accept without giving in return. ”

    Two mothers had bought bottled water and placed a sticker(小贴纸) on all bottles with five different quotes（引述）：

1). Smile at everyone. You'll never know when someone may need it.

2). If Plan A does not work, there are 25 more letters in the alphabets.

3). Have a thirst for life. Every day is filled with possibilities.

4). In your thirst for knowledge, be sure you don't drown in all the information.

5). Dig your well before youh're thirsty.

    The bottle I have has quoted No.5. A sudden change of attitude opened up between me, the mothers and the children. We are no longer strangers to each other. We were having such a great time chatting and I ended up helping them give away the rest of the bottled water.

    One young lady was so thankful that she happily accepted the water and said it was the best thing that happened to her all day since she had a bad day at work. A man refused and walked away saying “No, thanks”. A couple kept on bowing to us in gratitude. When it was all done, the children and I were giving each other high-five. It was so much fun. I think I had more fun doing this than the mothers and the children.

    Chinese audiences seemed not to have been satisfied

    Chinese audiences seemed not to have been satisfied with the third season of the highly anticipated food documentary A Bite of China.

    Even though the series has maintained high viewership ratings since its comeback last week, much higher than other programs aired at the same time, the ranking on Douban, a social networking website featuring films, literature and events, slipped to 4.2 out of 10, as of Tuesday, compared with 9.3 and 8.4, respectively, for the first two seasons.

    Picky viewers complain that some of the narration is not accurate, while others pinpoint misleading content. At the same time, food blogger questioned whether it is appropriate to give a close-up shot of the poisonous plant Nandina (南天竹) in a food program.

    A Bite of China, which debuted in 2012, became hugely popular nationwide for its quality introduction of some rarely-known and mouth-watering domestic cuisine. In the new show, however, watchers are not satisfied with "irrelevant" food references, such as lipsticks made of Chinese traditional medicine and martial arts films.

    The first episode introduced a hand-made iron frying pan from east China's Shandong province, which prompted thousands of Chinese Internet users to buy one from China's leading e-commerce website Tmall in the next few days. Sales of the pan at "Zhensanhuan" surged 6,000 times compared with a year ago, according to Beijing Youth Daily.

    In response to overwhelming criticism and questions, A Bite of China production crew responded on Weibo that they seek innovation despite the risks following the first two phenomenal seasons.

    "It is unavoidable to make comparisons with the first two, and some audiences may not accept the changes," the crew said. "We explore the culture and civilization behind food, and give food a historic touch. That's why we feature culinary (烹饪的) tools, feast and rituals, as well as a healthy diet to show Chinese wisdom and philosophy, which has not been shown in any food programs before."

    People in South Korea who feel they can no longer bear the stress of everyday life now can choose to stay in a prison to relax and think deeply.

    In a society where pressure to do well in school and find highly-paid jobs is intense, a former lawyer came up with an extreme relaxation idea. Kwon Yong-seok created the "Prison Inside Me" —a stress-reduction center with a punishment theme. People come here to cut themselves off from the outside world and pay to be kept in 60-square-foot (5.6-square-meter) cells (囚室).

    Located on the outskirts of Hongcheon, about 58 miles (93 km) northeast of Seoul," Prison Inside Me" came to life after Mr. Kwon voluntarily asked to spend time behind bars for" healing reasons," but his request was turned down." I didn't know how to stop working back then," he said." I felt like I was being swept away against my will, and it seemed I couldn't control my own life." So, Kwon and his wife Roh Ji-hyang decided to take matters into their own hands, and designed and built a prison-like spiritual center. The construction was completed in June last year and cost about 2 billion won ($19 million).

    The facility includes 28 cells, furnished with only a toilet, a sink and a small table, where guests can spend time alone, thinking about life and enjoying private thinking periods. Moreover, guests can also join group thinking periods in the hall, where they are given instructions on how to free themselves from what Mr. Kwon calls the "inner prison" to find inner peace.

    According to the Wall Street Journal, hundreds of stressed South Koreans are checking in at the stress-reduction facility to think about their lives and regain control of it. A two-night stay at" Prison Inside Me" costs 150,000 won ($146).

    Mr. Kwon and his wife explained that at the beginning they had a different plan for the" relaxation center," and imagined a longer stay for their guests, but, given that people weren't able to take more time off, they had to reduce the length of stays to just two days.

    Park Woo-sub, a guest at" Prison Inside Me," said the experience helped him a lot." This is my third time in prison. Being kept in a prison makes me hard to breathe, but it also offers time to focus only on me and spend some quiet time with myself."

    Others said the experience would have been more helpful if the conditions had been poorer, like in a real prison.

    How does an ecosystem（生态系统）work? What makes the populations of different species the way they are? Why are there so many flies and so few wolves? To find an answer, scientists have built mathematical models of food webs, noting who eats whom and how much each one eats.

    With such models, scientists have found out some key principles operating in food webs. Most food webs, for instance, consist of many weak links rather than a few strong ones. When a predator（掠食动物）always eats huge numbers of a single prey（猎物）, the two species are strongly linked; when a predator lives on various species, they are weakly linked. Food webs may be dominated by many weak links because that arrangement is more stable over the long term. If a predator can eat several species, it can survive the extinction（灭绝）of one of them. And if a predator can move on to another species that is easier to find when a prey species becomes rare, the switch allows the original prey to recover. The weak links may thus keep species from driving one another to extinction.

Mathematical models have also revealed that food webs may be unstable, where small changes of top predators can lead to big effects throughout entire ecosystems. In the 1960s, scientists proposed that predators at the top of a food web had a surprising amount of control over the size of populations of other species—including species they did not directly attack.

    And unplanned human activities have proved the idea of top-down control by top predators to be true. In the ocean, we fished for top predators such as cod on an industrial scale, while on land, we killed off large predators such as wolves. These actions have greatly affected the ecological balance.

    Scientists have built an early-warning system based on mathematical models. Ideally, the system would tell us when to adapt human activities that are pushing an ecosystem toward a breakdown or would even allow us to pull an ecosystem back from the borderline. Prevention is key, scientists says because once ecosystems pass their tipping point（临界点）, it is remarkably difficult for them to return.