It was a cold night in Washington, D. C., and I was heading back to the hotel when a man approached me. He asked if l would give him some money so he could get something to eat. I'd read the signs "Don't give money to beggars." So I shook my head and kept walking.

    I wasn't prepared for a reply, but he said, "I really am homeless and I really am hungry! You can come with me and watch me eat!" But I kept on walking.

    The incident bothered me for the rest of the week. I had money in my pocket and it wouldn't have killed me to hand over a buck or two even if he had been lying. Flying back to Anchorage, I couldn't help thinking of him. I tried to rationalize (找借口)my failure to help by thinking government agencies, churches and charities were there to feed him. Besides, you're not supposed to give money to beggars.

    Somewhere over Seattle, I started to write my weekly garden column for The Anchorage Daily News. Out of the blue, I came up with an idea. Bean's Cafe, the soup kitchen in Anchorage, feeds hundreds of hungry Alaskans every day. Why not try to get all my readers to plant one row in their gardens dedicated to Bean's? Dedicate a row and take it down to Bean's. Clean and simple.

    The idea began to take off. Readers would fax or call me when they got something in their garden. Those who only grew flowers donated them. Food for the spirit.

    In 1995, the Garden Writers Association of America held their annual convention in Anchorage and after learning of Anchorage's program, Plant a Row for Bean's became Plant a Row for the Hungry. The original idea was to have every member of the Garden Writers Association of America write or talk about planting a row for the hungry sometime during the month of April.

    As more and more people started working with the Plant a Row idea, new changes appeared unexpectedly. Many companies gave free seed to customers and displayed the logo, which also appeared in national gardening publications. Row markers with the Plant a Row logo were delivered to gardeners to set apart their "Row for the Hungry."

    Garden editor Joan Jackson, supported by The San Jose Mercury News and California's nearly year-round growing season, raised more than 30,000 pounds of fruits and vegetables her first year, and showed GWAA how the program could really work. Texas fruit farms donated food to their local food bank after being inspired by Plant a Row. Today the program continues to thrive and grow.

    I am surprised that millions of Americans are threatened by hunger. If every gardener in America--and we're seventy million strong--plants one row for the hungry, we can make quite a decrease in the number of neighbors who don't have enough to eat. Maybe then I will stop feeling guilty about abandoning a hungry man I could have helped.

    Camberwell College Swimming Pools

    Camberwell College of Arts has one 50m (Olympic sized) pool with a depth of 2m throughout, and one 25m pool with a 1m shallow end and a 4m deep end. Both pools may be used by the general public at certain times.

    50m Pool

    The pool is often used for classes, but the general public may use two lanes（泳道）for lane swimming at the following times.

    Monday:        06:30-11:30 and 19:00-21:00

    Tuesday:        06:30-11:30 and 18:00-21:00

    Wednesday:    06:30-13:30 and 17:30-21:30

    Thursday:    06:30-13:30

    Friday:        06:30-13:30

    Weekends:    09:00-17:00

    Children under the age of 14 must be accompanied by an adult.

    Please note that during College holidays, these times will be different. Call 04837 393560 for up-to-date information.

    25m Pool

    The 25m pool is available for recreational (non-lane) swimming from 07:00-09:00 and 12:30-13:30 on weekdays, and 10:00-16:00 on Saturdays.

    Children aged 12 and under must be accompanied.

    We regret that the 25m pool will be closed for redecoration between 21st July and 18th August. The men's changing rooms will be closed for the week beginning 19th August, and the women's changing rooms will be closed the following week. Alternative（可选用的）changing rooms will be made available. We're sorry for this.

    Would it surprise you to learn that, like animals, trees communicate with each other and pass on their wealth to the next generation?

    UBC Professor Simard explains how trees are much more complex than most of us ever imagined. Although Charles Darwin thought that trees are competing for survival of the fittest, Simard shows just how wrong he was. In fact, the opposite is true: trees survive through their co-operation and support, passing around necessary nutrition（营养）“depending on who needs it”.

    Nitrogen（氮）and carbon are shared through miles of underground fungi（真菌）networks, making sure that all trees in the forest ecological system give and receive just the right amount to keep them all healthy. This hidden system works in a very similar way to the networks of neurons（神经元）in our brains, and when one tree is destroyed, it affects all.

    Simard talks about “mother trees”, usually the largest and oldest plants on which all other trees depend. She explains how dying trees pass on the wealth to the next generation, transporting important minerals to young trees so they may continue to grow. When humans cut down “mother trees” with no awareness of these highly complex “tree societies” or the networks on which they feed, we are reducing the chances of survival for the entire forest.

    “We didn't take any notice of it” Simard says sadly. “Dying trees move nutrition into the young trees before dying, but we never give them chance.” If we could put across the message to the forestry industry, we could make a huge difference towards our environmental protection efforts for the future.

    Papa was a ranger. He worked with horses. He always wore clean clothes with a hat even when he worked. His hat was always the same kind of a cowboy hat—large black hat of heavy wool. He wore his hat full and high. I think he wanted to look taller than he really was.

    Mama was proud of the way he looked when he wore his hat and his best clothes. But in some way she got the idea that papa would lose his hair if he kept wearing a heavy wool cowboy hat in the hot weather. She began to talk about his hat.

    "Papa, "she said one day, "why don't you get a nice cool straw hat? That heavy wool cowboy hat may cause losing hair!" Papa laughed at her and explained that the horses wouldn't recognize him if he changed the hat. But she didn't believe him.

    Mama talked and talked about the hat all summer long. At last papa answered, a little angry, "It would not the cowboy hat but a wife's talking about the hat that makes me lose my hair."

    Mama had a very serious look on her face. She went straight out and later came home with a straw hat. It was a bad year for ranger and we didn't have much money. She thought that if she spent the money for a straw hat, papa would wear it. When papa saw the hat, his face got red. Without a word, he pulled the straw hat down over his head until it hid his eyes and went on to train the horses.

    He was a good ranger and gentle to his horses. But as papa got close to the horses this time, they jumped high into the air, raising their front feet. All of them ran around in the rounded field and then raced toward the barn. Papa began to shout "Woo boys. Steady boys, steady." But there was nothing equal to.

    Papa walked back straight to the stove in the kitchen, pushed the straw hat deep down into the fire then turned to mama, in a way that even frightened me. "Now listen to me, mama. Understand this I will never wear a straw hat or any other kind of hat my horses do not like. "Then he put on his wool cowboy hat and walked out of the house.

    I never heard mama talk any more about hats. Perhaps, that is why when papa died many years later, there was a round spot on the top of his head where there was no hair.

    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.

    Darwin noted that some human emotional expressions might have started as part of a physiological function: for example, exposing the teeth to bite food. The function, however, took on meaning and became a form of communication which signals anger.

    The same may be true for the animals. Baby monkeys cry for attention. They also cry to signal to an adult that they want to be carried.

    "Chimpanzees do make upset voice when they are being weaned (断奶) by their mothers or have lost their mothers or another individual, " says Anne Pusey, a professor at the University of Minnesota. "They whimper (呜咽) and cry and scream. When we hear these calls, the emotion involved seems obvious. However, they do not weep in the sense of producing tears. "

    The Iowan researchers can cause the same crying sounds by producing large decreases and then increases in blood flow. The blood flow also goes down when baby rats get cold. Thus, they conclude baby rats cry in the same way that we sneeze. Of course the rat baby could be crying because he's cold and wants his mother to know.