Miss Parker taught physics in a New York school. Last month she explained to one of her classes about sound ,and she decided to test them to see how successful she had been in her explanation. She said to them, “Now I have a brother in Los Angeles. If I was calling him on the phone and at the same time you were 75 feet away, listening to me from across the street, which of you would hear what I said earlier, my brother or you and for what reason?”

    Tom at once answered, “Your brother. Because electricity travels faster than sound waves.”“That's every good,” Miss Parker answered; but then one of the girls raised her hand, and Miss Parker said.“Yes, Kate.”

    “I disagree,” Kate said.“Your brother would hear you earlier because when it's 11 o'clock here it's only 8 o'clock in Los Angeles.”

    One afternoon I toured an art museum while waiting for my husband to finish a business meeting. I was looking forward to a quiet view of the art works.

    A young couple viewing the paintings ahead of me chatted nonstop between themselves. I watched them a moment and decided the wife was doing all the talking. I admired his patience for putting up with her continuous talk. Distracted by their noise, I moved on.

    I met with them several times as I moved through the different rooms of art. Each time I heard her constant burst of words, I moved away quickly.

    I was standing at the counter of the museum gift shop making a purchase when the couple came near to the exit. Before they left, the man reached into his pocket and pulled out a white object. He extended it into a long stick and then tapped his way into the coatroom to get his wife's jacket.

    “He's a brave man.,” the clerk at the counter said, “Most of us would give up if we were blinded at such a young age. During his recovery, he made a promise that his life wouldn't change. So, as before, he and his wife come in whenever there's a new art show."

    “But what does he get out of the art?” I asked. “He can't see.”

    “Can't see? You're wrong. He sees a lot. More than you or I do,” the clerk said. “His wife describes each painting so he can see it in his head.”

    I learned something about patience, courage and love that day. I saw the patience of a young wife describing paintings to a person without sight and the courage of a husband who would not allow blindness to change his life. And I saw the love shared by two people as I watched this couple walk away.

    Nola (August 21, 1974 -November 22, 2015) was a northern white rhino(犀牛) who lived at the San Diego Zoo Safari Park near Escondido, California. At her death, she was one of only four remaining northern white rhinos in the world. The other three lived in Kenya. World Rhino Day, held on September 2, is to raise awareness(意识) of the less than 30,000 other rhinos left on Earth.

    “Rhinos need our help today, not tomorrow,” Nola's lead keeper Jane Kennedy said. “Last year we lost over 1,200 rhinos just in South Africa. If we continue to lose more than 1,000 rhinos a year, in 10 to 20 years all the rhinos on the planet will be gone.”

    “Unfortunately, most animals are in danger of dying out because of humans,” Kennedy says.“ Humans have either poached animals, or because there are over seven billion of us, we've taken up too much of the world's resources ”. Poachers illegally hunt rhinos for their horns. They sell the horns for thousands of dollars per pound, to be used for art, jewelry, and decorations. Experts believe that one rhino is poached every eight hours.

    In 1975, the San Diego Zoo Institute for Conservation Research started the Frozen Zoo, a program through which researchers have collected cell (细胞) samples from more than 8,000 different types of animals, including the northern white rhino. Scientists hope that by studying the rhino cells, they will get greater understanding of it, and will find ways to increase its numbers.

    Jane Kennedy describes World Rhino Day as “a celebration of rhinos along with an awareness campaign for everybody across the world to know that rhinos need our help.” At the San Diego Zoo, children and adults are welcome to visit and speak with zookeepers to learn about rhinos. But you don't have to live in San Diego to celebrate World Rhino Day. It is observed around the world, with zoos and wildlife parks holding special events and programs to teach people about rhinos, and enable them to see the animals up close. For more information, go to www.worldrhinoday.org.

        Let us all raise a glass to AlphaGo and the advance of artificial intelligence. AlphaGo, DeepMind's Go-playing AI, just defeated the best Go-playing human, Lee Sedol. But as we drink to its success. We should also begin trying to understand what it means for the future.

    The number of possible moves in a game of Go is so huge that in order to win against a player like Lee. AlphaGo was designed to adopt a human—like style of gameplay by using a relatively recent development--deep learning. Deep learning uses large data sets, “machine learning” algorithms （计算程序） and deep neural networks to teach the AI how to perform a particular set of tasks. Rather than programming complex Go rules and strategies into AlphaGo, DeepMind designers taught AlphaGo to play the game by feeding it data based on typical Go moves. Then, AlphaGo played against itself, tirelessly learning from its own mistakes and improving its gameplay over time. The results speak for themselves.

    Deep learning represents a shift in the relationship humans have with their technological creations. It results in AI that displays surprising and unpredictable behaviour. Commenting after his first loss, Lee described being shocked by an unconventional move he claimed no human would ever have made. Demis Hassabis. one of DeepMind's founders, echoed this comment：“We're very pleased that AlphaGo played some quite surprising and beautiful moves.”

    Unpredictability and surprises are—or can be—a good thing. They can indicate that a system is working well, perhaps better than the humans that came before it. Such is the case with AlphaGo. However, unpredictability also indicates a loss of human control. That Hassabis is surprised at his creation's behaviour suggests a lack of control in the design. And though some loss of control might be fine in the context of a game such as Go, it raises urgent questions elsewhere.

    How much and what kind of control should we give up to AI machines? How should we design appropriate human control into AI that requires us to give up some of that very control? Is there some AI that we should just not develop if it means any loss of human control? How much of a say should corporations, governments, experts or citizens have in these matters? These important questions, and many others like them, have emerged in response, but remain unanswered. They require human, not human - like, solutions.

    So as we drink to the milestone in AI, let's also drink to the understanding that the time to answer deeply human questions about deep learning and AI is now.

    By analyzing the fossilized teeth of some of our most ancient ancestors, a team of scientists led by the universities of Bristol (UK) and Lyon (France) have discovered that the first humans significantly breastfed their infants (婴儿) for longer periods than their contemporary relatives.

    The results, published in the journal Science Advances, provide a first insight into the practice of weaning (断奶)that remain otherwise unseen in the fossil record.

    The team sampled minute amounts from nearly 40 fossilized teeth of our South African fossil relatives, early Homo, Paranthropus robustus and Australopithecus africanus. They measured the proportions of their stable calcium isotopes (同位素）in the tooth enamel(牙釉质), which are a function of the mother milk intake by infants. They show that early Homo offspring(后代) was breastfed in significant proportions until the age of around three to four years, which likely played a role in the apparition of traits that are specific to human lineage(血统), such as the brain development.

    In contrast, infants of Paranthropus robustus, that became extinct around one million years ago and were a more robust species in terms of dental anatomy, as well as infants of Australopithecus africanus, stopped drinking sizeable proportions of mother milk in the course of the first months of life.

    These differences in nursing behaviors likely come with major changes in the social structures of groups as well as the time between the birth of one child and the birth of the next.

    One of the study's lead authors, Dr Theo Tacail said: "The practice of weaning -- the duration of breastfeeding, age at non-milk food introduction and the age at cessation of suckling -- differs among the modern members of the hominid family which includes humans and modern great apes: orangutan, gorillas, chimpanzees and bonobos.

    The development of such behavioral differences likely played major roles in the evolution of the members of human lineage, being associated for instance with size and structure of social groups, brain development.

    However, getting insights into these behavioral changes from fossils that are millions of years old is a challenge and, so far, little evidence allow discussing nursing practices in these fossil species.

    The findings stress the need for further exploration of calcium stables isotopes compositions in the fossil record in order to understand the co-evolution of weaning practices with other traits such as brain size or social behaviors."

http://www.dentaldailynews.com/first-human-ancestors-breastfed-for-longer-than-contemporary-relatives/

https://www.sciencedaily.com/releases/2019/08/190829115427.htm