Jealousy is such a powerful emotion that at least one study has characterized it as the third leading cause of non-accidental homicide(杀人) in all cultures. In a recently published study, researchers experimented with dogs to see whether they, like humans, have the nature of jealousy.

In an experiment, the authors took 36 dogs—along with their owners—and observed the dogs' behavior as their masters interacted with three non-living objects. One object was a children's book, which they read aloud; another object was a plastic pumpkin lantern; and the third was a mechanical stuffed dog that gave out a bark when the owner pressed a button.

    Former studies concluded that babies were probably capable of jealousy. In the experiment, their mothers showed attention to a life-like doll instead of their child, and other objects. The babies were reportedly more likely to respond with “negative” behavior if their mother turned to pay her attention to the doll.

    In the dog experiment, authors instructed the dog owners to push the bark button on the stuffed dog's head, and then speak to it sweetly, while ignoring their own dog. After that, they showed attention to the pumpkin lantern, and read the children's book, while also ignoring their dog.

    It is interesting to see the dogs were far more likely to act aggressively when their owners spoke to the stuffed dog than when they paid attention to the other objects. One-fourth of the dogs snapped at the stuffed dog, while only one dog snapped at the lantern or the book. The dogs were also more likely to push or touch their owners as they interacted with the mechanical dogs, and tried to get in between the owner and the stuffed dog more frequently than the other objects.

    “One possibility is that jealousy developed in species of many young relying on the parents, the young compete for parental resources such as food, attention, care, and affection,” the authors wrote.

    For years I have had no idea what I have been doing with my life. I was a 30-year-old lawyer in New York. But being a lawyer was never my dream or goal in life. I honestly wanted to be a writer. I have a great imagination and would write amazing stories in my head. But I always knew that being a writer was never possible for me because it was a better financial decision to stay a lawyer.

    Recently, I couldn't fall asleep at my usual time of 10 p. m. and when I did fall asleep I had the same dream over and over again. The dream starts with me in the ocean trying to go for a swim and I'm searching for something, but I start to drown and have no control over my body. Then a light shines through the waters and when I look up all I can see is myself in a bright white room writing a novel. Then I hear a voice say repeatedly, “Now is the time to try something new!”

    It wasn't just a dream; it was my opportunity to make something good out of my life. That afternoon, I quit my job at the law firm and I couldn't have been any happier. My life started at 30, and every day since that point I haven't stopped enjoying life. I started to write and have been on the best-sellers list for the last two months. Things have definitely turned around.

    Change is a good thing; it gives us an opportunity to take a chance. So my two favorite words I live by and so should you are “change and chance”.

    Our cities have never been denser, taller, or busier than they are now, and with that, comes the constant battle for land. But if we look at aerial images of any city center, we can quickly spot plenty of unused space — the rooftops.

    So what can we use this precious resource for? In a growing number of high-density cities, some of it is dedicated to recreation — everything from bars and pools, to soccer pitches and running tracks can now be found atop skyscrapers. But when a rooftop offers access to sunlight, there are two more obvious candidates for its use - agriculture and solar power.

    Green roofs have been growing in popularity for more than a decade, and in some cases, growing in scale too. Green roofs can provide a habitat for birds and insects in an otherwise hostile environment.

    Cities can be several degrees warmer than the surrounding countryside. Green roofs come with the added benefit of mitigating the dreaded urban heat island effect. Trees and green spaces can absorb shortwave radiation, and use it to evaporate water from their leaves — a kind of 'double cooling' effect.

    With food security and urban nutrition ever-higher on the agenda for the United Nations, there's also a worldwide movement of using green roofs for hyper-local food production. In regions with suitable climates, hundreds of different vegetables, fruits, and salad leaves can be grown on rooftops.

    But what about solar power? With so many cities now stopping using fossil fuels, and the costs of solar panels dropping dramatically, PV systems have become the 'go to' option for generating distributed power in built-up areas. And, even with standard commercial panels, the energy gains are dramatic. It is estimated that rooftop PV systems could generate almost 40% of electricity demands nationwide.

    There's no doubt that in both cases, a network of 'productive rooftops' could benefit the local community by supplying a portion of a necessary resource — either food or electricity — while also reducing their environmental burden. But is one better than the other?

    This was the question posed by researchers from MIT and the University of Lisbon in a recent paper in the journal Cities. Focusing on the rooftops of a mixed-use neighborhood in Lisbon, they carried out a Cost-Benefit Analysis. Starting with existing data on everything from installation costs and resources used, to carbon footprint and yield, they modelled the impact that each installation would have on the local community over a period of 50 years.

    And by looking at it that way, they concluded that for Lisbon, the use of rooftops for food production could yield significantly higher local value than solar PV energy generation. Of course, this is very site-specific. There is no one-size-fits-all solution to make cities more sustainable, and anyone who tells you otherwise is massively over-simplifying a complex issue. Now, all I hope is that some of those decision makers start using it.

    On Wednesday, January 13th, I performed on stage for the first time. As someone who takes part in so many activities, it's extremely difficult to find the time to be a part of any production. For me, it was a once-in-a-lifetime opportunity to try acting through the Senior Play Project.

    Auditions (试镜)came first. They weren't particularly difficult, more to see who may be a better fit tor certain roles. We were told our roles in the various plays, and started to work immediately.

    I was unsure of how I was as an actor, and I had to learn a lot fast: actions, my place in the story, my reactions, and countless other small details... As I began to improve as an actor, I was able to understand my characters better.

    My first character is a man named Roger who is a senior advisor to a presidential candidate in a play called "The Spot." He's a short-tempered guy who says what he wants and takes what he wants to assist his candidate in today's tough political races. He's on the set of The Spot, an advertisement for the candidate, to make sure everything runs smoothly and that any problems are dealt with quickly and efficiently.

    While I had really interesting characters, and the plays were funny and such a great experience to act in, I really love the Senior Play Project for the people. I worked with 12 other seniors who not only loved what they were doing, but offered help and advice throughout my entire learning process.

    Between the lights, sounds, costume and makeup, and plenty more, theatre is a team sport just like basketball or baseball. There are no small parts; there is no one who isn't needed. I've learned to appreciate live theatre, and the effort that every person in the show, both onstage and offstage, puts into it.

    A robot created by Washington State University (WSU) scientists could help elderly people with dementia (痴呆) and other limitations live independently in their own homes.

    The Robot Activity Support System or RAS, uses sensors installed in a WSU smart home to determine where its residents are, what they are doing and when they need assistance with daily activities. It navigates (定位) through rooms and around obstacles to find people on its own, provides video instructions on how to do simple tasks and can even lead its owner to objects like their medication or a snack in the kitchen.

"RAS combines the convenience of a mobile robot with the activity detection technology of a WSU smart home to provide assistance in the moment, as the need for help is detected," said Bryan Minor, a postdoctoral researcher in the WSU School of Electrical Engineering and Computer Science.

    Currently, an estimated 50 percent of adults over the age of 85 need assistance with every day activities such as preparing meals and taking medication and the annual cost for this assistance in the US is nearly $2 trillion. With the number of adults over 85 expected to triple by 2050, researchers hope that technologies like RAS and the WSU smart home will relieve some of the financial strain on the healthcare system by making it easier for older adults to live alone.

    RAS is the first robot researchers have tried to incorporate into their smart home environment. They recently published a study in the journal Cognitive Systems Research that demonstrates how RAS could make life easier for older adults struggling to live independently.

    "While we are still in an early stage of development, our initial results with RAS have been promising," Minor said. "The next step in the research will be to test RAS' performance with a group of older adults to get a better idea of what prompts, video reminders and other preferences they have regarding the robot."

Once a blind man fell flat on his face, which was awful but finally harmless. His service dog, however, was trained lo tum to an adult if the owner had an epileptic seizure (癫瘤发作). While the dog did what it was taught, the first person it found was merely annoyed but not alarmed. Thankfully, the dog's owner was not in the situation of medical emergency. But the experience inspired him to share this information on social media, "If a service dog without a person approaches you, it means the person is down and in need of help," the owner explained. "Don't get scared, don't get annoyed, and follow the dog! If the first person doesn't cooperate, it moves on.

Referring to the accident, a TV presenter asked a dog trainer, Olivia, some basic questions about service dogs, including how humans should react if an unaccompanied service dog approaches them.

"What they're going to do is sniff and gently push your leg," the trainer explained, specifically noting that service dogs are not usually trained to jump or bark. "If you see a dog in a vest without a person around it, follow it." When asked if one should say something to indicate they're prepared to follow the dog, Olivia said," there's no clear command. Just start walking wherever the dog leads."

Olivia concluded the TV show by adding that those who rely on service dogs could train their companions to move along to someone else, if the first person the dog came upon reacted negatively to its request. Doing so could finally save the owner's life.