While dog keepers realize their dogs can read their moods accurately, scientists have always been a little doubtful. Now thanks to some researchers at the University of Veterinary Medicine in Vienna, Austria, we finally have some convincing evidence.

    For their study, biologist Corson Miller and his team exposed eleven selected dogs to digital images of women that were either angry or happy. Half the dogs were rewarded for touching the screen when shown a happy face, while the other half got their treat for selecting those that appeared angry.

    Interestingly, the dogs were not provided with the entire face. Some dogs were shown only upper halves while the others observed lower halves. That's because the scientists believe humans show their emotions on their entire face.

    After some training like how to recognize small differences like the wrinkles between the eyes or the changes in their shape that accompany the happy or angry expressions, the dogs were mostly able to identify the correct expression not only on a familiar face but on a strange face. The researchers concluded the dogs were smart enough to read human emotions.

    They also found those being trained to read angry expressions took a longer time to learn. They guess it may be because dogs find angry faces disgusting, causing them to withdraw quickly. However, once the smart dogs realized they were getting rewarded, the trepidation seemed to disappear. In fact, the dogs had such a good time playing the computer "game" that scientists had a hard time keeping them away from the touch screens after the study was completed.

    The researchers also noticed only dogs with a male owner had a harder time understanding the expressions correctly. Since the touchscreen models were all females, this confirmed what has been observed in previous studies—dogs are more efficient at reading facial expressions of people that are the same gender as their owner.

    It's official. Denmark—as well as being the world's best country to live in for women with the second-happiest people and one of the best healthcare systems in Europe—has the most contented babies. Or, at least, the ones who cry the least. According to research published in the Journal of Pediatrics, Danish, German and Japanese babies cry the least, while British, Canadian and Italian babies cry the most.

    “I'm not surprised,” Danish parenting expert and co-author of The Danish Way of Parenting Jessica Alexander tells me. “The first year of a child's life is considered so important in Denmark. Danish parents are much less stressed because they get good maternity and paternity leave (孕产假). The atmosphere is much calmer and, if mothers are getting more time off, that goes hand in hand with less stress, more contact, more routines and less crying.” She pauses before throwing in a final tip: “Oh, and Danish babies sleep outdoors a lot.”

    In Denmark, a woman is given four weeks pregnancy leave followed by 52 weeks of paid leave that can be shared between parents. And Alexander thinks there is another important reason why Danish babies cry less: breastfeeding. “It's just the done thing in Denmark,” she says of a country that has the world's highest breastfeeding rates. “In other countries, there are continual discussions about whether you should or shouldn't breastfeed. In Denmark, breastfeeding has never gone out of style. And everyone does it for a year.”

    For Iben Sandahl, Alexander's co-author, it comes down to the Danish attitude to life in general. “We are an honest and pure people,” she tells me. “We are surrounded by social support and are less likely to become angry, sad or annoyed when our babies are crying. And we are good at embracing (拥抱) all kinds of feelings, so we aren't scared. Instead, we try to connect with the babies when they cry. It's how babies communicate and it's about trying to understand it.”

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    Founded in 1764 by French traders, St. Louis today is the fifteenth largest urban area in the United States. There are many attractive destinations for tourists.

American Kennel Club Museum of the Dog

    Dog lovers who visit St. Louis won't want to miss this 14,000-square-foot museum. Inside are over 500 paintings, prints, watercolors, and a variety of other dog art objects.

    The Museum is open year round, Tuesday through Saturday 10 AM to 4 PM, and Sunday 1 PM to 5 PM. Admission is $ 5 for adults, $ 2.50 for seniors, and $1 for children up to 14.

Anheuser Busch Brewery

    The Anheuser Buxch Brewery tour is not just for beer lovers. The tour includes the historic Brew House. Then the tour continues to the modern Bevo Packaging Plant. The best will be the Budweiser Clydesdale stables. The tours are always free.

Gateway Arch

    Designed by Eero Sarinen and Hannskari Bandel, it took over two years and 900 tons of stainless steel to build. It is the tallest of the country's National Monuments. The Arch is part of the Jefferson National Expansion Memorial. About one milion people per year come to the top of the Arch, where there is an observation platform providing a great view of the city.

St. Louis Zoo

    First version of the St. Louis Zoo opened in 1904 at the St. Louis World's Fair, but in the century since it has grown into one of the chief zoos in the world. The passenger train takes visitors around the Zoo, which contains over 9,000 animals of over 800 species.

    The Zoo is open every day but Christmas and New Year, with summer hours of 8 AM to 7 PM, and hours the rest of the year of 9 AM to 5 PM. Admission to the Zoo is free.

    Reducing plastic waste isn't easy because the cheap material is found in almost every household item. Now, a delicious and nutritious solution has come up to help reduce our dependence on this environmental hazard.

    David Christian, the co-founder of Evoware, says the idea of creating the biodegradable (生物降解的) products came from concern at the country's high pollution rate. Indonesia is home to four of the world's worst polluted rivers. Since single-use packaging is a large contributor to the problem, Evoware decided to deal with that first.

    After investigating various materials, the company settled on seaweed. Unlike com, commonly used for biodegradable containers, seaweed does not require resources like water or large amounts of space. Since Indonesian farmers already harvest more seaweed than they can sell, it's easy for the company to find the material.

    Though they will not reveal their production process, Evoware says the seaweed packaging contains no chemicals and is safe to consume. The company has also invented single-use cups, which can break down 30 days after they're thrown away.

    While replacing plastic with the seaweed products may seem appealing to most of us, it is a hard-sell in Indonesia. According to Christian, “The awareness to reduce single-use plastic is still very low. This makes our bioplastic unnecessary.” Also a factor is the cost, which is higher than using plastic. Hopefully, Evoware will succeed in convincing Indonesians and people worldwide that switching to their products will be helpful to protecting our beautiful planet.

    Plastic is easy, convenient, cheap and long-lasting, but it does great harm to the environment.

    Since plastic entered mass production, 8 billion tons have been produced – and we aren't very good at recycling. By 2015, 6,945 tons of plastic waste had formed, with around 9 percent of it getting recycled. About 79 percent of it ends up in landfills or around the environment, including the ocean. We may end up drowning in plastic before long.

    Chemists at Colorado State University have found a polymer（聚酯）that has many of the qualities of plastics – it's light, strong, durable and heat-resistant – but that can be changed back to its original small-molecule（分子）state for complete recycling. Even after being recycled, the polymer can be turned back into its plastic-like state, and this can be done quickly and cheaply.

    This new polymer has all the good qualities of plastics, yet it is relatively easy to make and to recycle. Making it requires room temperature conditions, a short reaction time to bond the monomer（单体）into polymers and only a small amount of the catalyst（催化剂）remains in the end product. It has a high molecular weight, stands up to heat and generally behaves like plastic. Recycling it requires similarly little effort. Mild lab conditions are required and so is a catalyst. Once applied, the polymers are once again monomers in a matter of minutes and can be used to create another product.

    But don't get too excited about this just yet. Scientists stressed that the polymer isn't ready for mass products just yet. There's still plenty of development to do, including making it more economical to produce and recycle.

    They say that an apple a day keeps the doctor away. Well, there is one lady who believes that it's actually chocolate. At 102 years of age, she's living proof.

    According to Boonville, Indiana's Eunice Modlin, a daily dose of chocolate has been the key to a long and healthy life. Specifically, two pieces of dark chocolate. It's not just Eunice who believes this.

    Many scientists have attributed the sweet to health benefits such as lower chances of cancer, cardiovascular disease, and diabetes.

    However, researchers believe that Eunice might be overlooking the fact that she has never smoked or drunk alcohol in her long life, and that chocolate might not be the significant cause of her longevity.

    "There are so many other factors to her long life and chocolate isn't the only one," nutritionist Vanessa Rissetto said. "Genes, her diet in general…are probably the main reasons."

    At any rate, Eunice is still alive and kicking. With four children, seven grandkids, 14 great-grandkids and 11 great-great grandkids, this lady has a big family.

    It must be noted that Eunice was also very athletic, being an archer in her 20s .Amazingly, she has lived through tough times such as the Great Depression and World War II .Also, the healthy blood runs through the veins of other family members. Eunice's brother is also still alive, at 101 years of age.

    No matter what you might think, Eunice's consumption of chocolate can't be ignored. In 2015, a BMJ study showed that a daily treat of one small bar would give the consumer 23% less chance of having a stroke (中风).

    What is in the sweet that makes it so beneficial? Apparently, cocoa beans have flavonoids, plant nutrients that have useful antioxidants (抗氧化剂).

    "Not all chocolate is created equal," Rissetto warns. "Dark chocolate has more flavonoids than milk chocolate, and white chocolate—which does not actually contain chocolate—is not a good source of flavonoids."