About this time every year, I get very nostalgic(怀旧的)．Walking through my neighborhood on a fall afternoon reminds me of a time not too long ago when sounds of children filled the air，children playing games on a hill, and throwing leaves around in the street below. I was one of those children, carefree and happy. I live on a street that is only one block long. I have lived on the same street for sixteen years. I love my street. One side has six houses on it, and the other has only two houses, with a small hill in the middle and a huge cottonwood tree on one end.When I think of home, I think of my street. Only I see it as it was before. Unfortunately things change. One day, not long ago, I looked around and saw how different everything has become.Life on my street will never be the same because neighbors are quickly grown old, friends are growing up and leaving, and the city is planning to destroy my precious hill and sell the property to contractors.

    It is hard for me to accept that many of my wonderful neighbors are growing old and won't be around much longer. I have fond memories of the couple across the street, who sat together on their porch swing almost every evening, the widow next door who yelled at my brother and me for being too loud, and the crazy old man in a black suit who drove an old car. In contrast to these people, the people I see today are very old neighbors who have seen better days. The man in the black suit says he wants to die, and another neighbor just sold his house and moved into a nursing home. The lady who used to yell at us is too tired to bother any more, and the couple across the street rarely go out to their front porch these days. It is difficult to watch these precious people as they near the end of their lives because at once I thought they would live forever.

    The “comings and goings” of the younger generation of my street are now mostly “goings”as friends and peers move on. Once upon a time, my life and the lives of my peers revolved around home. The boundary of our world was the gutter at the end of the street. We got pleasure from playing night games or from a breathtaking ride on a tricycle. Things are different now, as my friends become adults and move on. Children who rode tricycles now drive cars. The kids who once played with me now have new interests and values as they go their separate ways. Some have gone away to college like me, a few got married, two went into the army, and one went to prison. Watching all these people grow up and go away makes me long for the good old days.

    Perhaps the biggest change on my street is the fact that the city is going to turn my precious hill into several lots for now homes. For sixteen years, the view out of my kitchen window has been a view of that hill. The hill was a fundamental part of my childhood life; it was the hub of social activity for the children of my street. We spent hours there building forts, sledding, and playing tag. The view out of my kitchen window now is very different; it is one of tractors and  dump trucks tearing up the hill. When the hill goes, the neighborhood will not be the same. It is  a piece of my childhood. It is a visual reminder of being a kid. Without the hill, my street will be just another pea in the pod.

    There was a time when my street was my world, and I thought my world would never change. But something happened. People grow up, and people grow old. Places changes, and with the change comes the heartache of knowing I can never go back to the times I loved. In a year or so, I will be gone just like many of my neighbors. I will always look back to my years as a child, but the place I remember will not be the silent street whose peace is interrupted by the  sounds of construction. It will be the happy, noisy, somewhat strange, but wonderful street I knew as a child.

    Humans and gorillas shared evolution for 23 million years. Their paths separated only six million years ago. Research on how gorillas communicate can help us understand human language development.

    Understanding how the brain works helps us see a connection between language development and non-verbal signs. These signs or movements include things like the way we move our hands or bodies or the different expressions our faces have in different social situations. A new study on gorillas showed that the right side of the body is controlled by the left part of the brain and it is also the location for language development.

    Two cameras were used to film all of one ape's movements. One of the first results was that gorillas use their right hands more when they are doing actions with their heads or mouths at the same time. This shows that there is a connection between how our brain works and the reason we use one side of our body more than the other. In addition, we can use the results of the study and our knowledge about brains to help us understand more about how language first developed in humans.

    Dr Forrester, who did the study, says the results can be useful in other ways, such as understanding language development in children. For example, some children have serious illness called “autism” which can stop them communicating normally with people. It might be possible to use the same study method to find out which children have this illness when they are very young. Doctors will then be able to start treatment early.

    I will absolutely be the first person to romanticize libraries. I come from a home with thirty-two bookcases, a count that does not include the several dozen boxes of books in the attic labeled "work" and "extra." All these books are courtesy of my parents, both of whom were English majors in their day and in whose footsteps I never hesitated to follow. My childhood dream was of a house with a claw-foot bathtub, stained glass, and (most importantly) an enormous library made of built-in shelves, a sliding ladder, and window seats in every window. As a high school girl, I began working at the county library near my house, following up on two summers of volunteering with their summer reading program. I was all starry eyes and romantic visions of alphabetizing the classics and discovering gems among the new arrivals. What I found instead was that the life of a library was nothing like my daydreams, but far more important than I could have imagined.

    There is no library that is only a library anymore. Modern libraries can't afford and don't try to be only a receptacle for free books. They offer classes, book groups, Internet access, resume and tax help, tutoring, and multimedia resources for anyone who might wander in. Librarians are equipped to help with research and give recommendations. Most libraries have access to interlibrary loans, making the acquisition of nearly any piece of material merely a matter of time. What makes libraries so unique and important, however, is none of the diversity of resources and opportunities for community that they most certainly provide.

    ____________________________________. Every building one enters today comes with some expectation of spending money. Restaurants require paying for service. Shops require the intention of purchasing something. Houses require rent. Anyone who has lived near the poverty line, whether or not they have actually been homeless, has felt the threatening pressure toward expenditure that permeates the public spaces of modern Western culture. Even a free restroom is becoming difficult to find, especially as growing cities experience ever-increasing space restrictions.

    In a library, no one is asked to pay anything simply to sit. For those with few resources besides time, this is a godsend. Libraries are unofficial playgrounds for low-income families on rainy days, homeless shelters in cold months, reprieves from broken homes for grade-school-age children. They are the last bastions of quiet and calm where nothing is asked of one but to exist. Many arguments have been made about how the library is an outdated institution offering outdated services—that in the twenty-first-century how-to books on building sheds and daily newspaper copies are obsolete and the funding used for libraries ought to be reallocated to other programs. I can only assume that those who make such arguments are people who have always been comfortable with the expenditures it takes to move through the world. For those people, libraries can be about books. But not everyone has the luxury of seeing past the space.

    Libraries, as they exist in the twenty-first century, are the only remaining public domain. In a library, anyone of any walk of life can come and go as they choose, and so long as they remain respectful of the space they can remain as long as they wish. Libraries welcome everyone, offering a place to be and easily accessible resources to the most vulnerable populations, whether in downtown Chicago or small-town Oklahoma. My childhood romantic vision of the library is still close to my heart, but the very real work that public libraries do today is so much more critical than a leather-bound edition of Homer or a graphic novel fresh off the press. Those are the things the library gives me, but libraries are for everyone.

    Depression(抑郁) can be a destructive illness, plaguing millions of people worldwide with feelings of sadness, hopelessness, and fatigue. Despite numerous antidepressant drugs, as many as a third of patients don't respond to medication. This has forced doctors to be more creative in finding different treatments for the condition.

    In the past two decades, researchers have tied depression to a seemingly unrelated condition: inflammation(炎症), the body's natural response to stress. It could rise from injury or inflection, or even emotional issues like an unhappy marriage or problems at work. Some amount of inflammation is generally beneficial, as it increases production of cytokines(致癌因子)，proteins that help us heal and protect us from the effects of overwork.

    But excessive cytokine levels, and the inflammation they bring on, could come at a cost—a number of studies suggests that high levels of cytokines could contribute to depression.

    Cytokines can reach the brain several ways: directly through the blood-brain barrier or indirectly by binding to nerve fibers elsewhere, which send signals to the brain to produce the inflammation molecules. In the brain, cytokines can disturb the production and release of several important signaling chemicals, including serotonin, dopamine and glutamate, which help control emotion, appetite, sleep, learning and memory. It's though that a lack of serotonin activity in the brain causes depression; most antidepressants increase the activity. But cytokines also have been shown to activate stress hormone signaling in the brain, which man also serve to develop depression.

    With all the evidence implicating inflammation in depression, doctors have been anxious to test anti-inflammatory drugs as a potential treatment. Four small studies published between 2006 and 2017 by research groups in Europe and Iran found that adults diagnosed with depression who took aspirin or another anti-inflammatory drug called Celecoxib, along with an antidepressant, got more relief from feelings of sadness, hopelessness, guilt and fatigue compared with those taking an antidepressant alone. However, Andrew Miller, a professor of psychiatry at Emory University, thought something was wrong in these small, limited studies. None of them looked at whether the participants had to have high levels of cytokines before they'd see a benefit from anti-inflammatory drugs.  "Unfortunately, much of the field has fallen into the trap of viewing inflammation as the be-all, end-all," Miller says. He and his colleagues wanted to see whether the effect of these drugs was limited to the depression patients with high cytokine levels, or if it helped all people diagnosed with depression.

    If you have a chance to go to Finland, you will probably be surprised to find how "foolish" the Finnish people are.

    Take the taxi drivers for example. Taxis in Finland are mostly high­class Benz with a fare of two US dollars a kilometer. You can go anywhere in one，tell the driver to drop you at any place，say that you have some business to attend to，and then walk off without paying your fare. The driver would not show the least signs of anxiety.

    The dining rooms in all big hotels not only serve their guests，but also serve outside diners. Hotel guests have their meals free, so they naturally go to the free dining rooms to have their meals. The most they would do to show their good faith is to wave their registration cards to the waiter. With such a loose check，you can easily use any old registration card to take a couple of friends to dine free of charge.

The Finnish workers are paid by the hour. They are very much on their own as soon as they have agreed with the boss at the rate. From then on they just say how many hours they have worked and they will be paid accordingly.

    With so many loopholes(漏洞) in everyday life, surely Finland must be a heaven to those who love to take "petty advantages". But the strange thing is that all the taxi passengers would always come back to pay their fares after they have attended to their business and that not a single outsider has ever been found in the free hotel dining rooms. And workers always give an honest account of the exact hours they put in. As the Finns always act on good faith in everything they do, living in such a society has turned everyone into a real “gentleman”.

    I was asked by a reader recently why so many animals seem to have pink ears, when their bodies are all different colours? The truth is that most animals actually don't have pink ears. Let us explain.

    Near the equator (赤道), where the climate is hot, animals are likely to have darker skin, including on their ears. Think of the African elephant, which has quite dark ears. In colder climates, skin colour is usually lighter and often pink.

    Why is skin colour different in different climates？Skin pigmentation, which is what gives skin its colour, can protect against sunburn and skin cancer (癌症). When animals live in colder parts of the world, they don't need it as much to survive. Light-coloured skin also helps animals stay warmer because it reduces heat loss, which is useful if you're in a colder climate.

    For most animals, the colour of their fur or other body covering has generally developed as camouflage. That allows animals to mix into the background and avoid being eaten, or for predators (捕食者) to remain hidden during hunting. One example is the sandy-coloured coat of the desert fennec fox, which uses camouflage for both hunting and hiding.

    By the way, in many animals, ears come in many different shapes and sizes. For example, in bats, the serval (a type of African wildcat) and the fennec fox, the ears are large compared to their body size—this helps them hear better because it allows them to sense more sound waves. Naked mole-rats have tiny ears because they need to dig a lot. Big ears would get in the way. The other downside of big ears is that you can lose a lot of body heat. That's why animals that live in really cold places, like the Arctic fox, have quite small ears.