Social change is more likely to occur in societies where there is a mixture of different kinds of people than in societies where people are similar in many ways. The simple reason for this is that there are more different ways of looking at things present in the first kind of society. There are more ideas, more disagreements in interest, and more groups and organizations with different beliefs. In addition, there is usually a greater worldly interest and greater tolerance in mixed societies. All these factors tend to promote social change by opening more areas of life to decision. In a society where people are quite similar in many ways, there are fewer occasions for people to see the need or the opportunity for change because everything seems to be the same. And although conditions may not be satisfactory, they are at least conventional and generally agreed.

    Within a society, social change is also likely to occur more frequently and more readily in the material aspects of the culture than in the non-material, for example, in technology rather than in values; in what has been learned later in life rather than what was learned early; in the less basic and less emotional aspects of society-than in their opposites; in the simple elements rather than in the complex ones; in form rather than in substance; and in elements that are acceptable to the culture rather than in strange elements.

    Furthermore, social change is easier if it is gradual. This is one reason why change has not come more quickly to Black Americans as compared to other American minorities, because of the sharp difference in appearance between them and white people.

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    Guide to Stockholm University Library

    Our library offers different types of studying places and provides a good studying environment.

    Zones

    The library is divided into different zones. The upper floor is a quiet zone with over a thousand places for silent reading, and places where you can sit and work with your own computer. The reading places consist mostly of tables and chairs. The ground floor is the zone where you can talk. Here you can find sofas and armchairs for group work.

    Computers

    You can use your own computer to connect to the wifi specially prepared for notebook computers; you can also use library computers, which contain the most commonly used applications, such as Microsoft Office. They are situated in the area known as the Experimental Field on the ground floor.

    Group-study Places

    If you want to discuss freely without disturbing others, you can book a study room or sit at a table on the ground floor. Some study rooms are for 2-3 people and others can hold up to 6-8 people. All rooms are marked on the library maps.

    There are 40 group-study rooms that must be booked via the website. To book, you need an active University account and a valid University card. You can use a room three hours per day, nine hours at most per week.

    Storage of study material

    The library has lockers for students to store course literature. When you have obtained at least 40 credits(学分), you may rent a locker and pay 400 SEK for a year's rental period.

    Rules to be followed

    Mobile phone conversations are not permitted anywhere in the library. Keep your phone on silent as if you were in a lecture and exit the library if you need to receive calls.

    Please note that food and fruit are forbidden in the library, but you are allowed to have drinks and sweets with you.

    Astronomers have taken the first ever image of a black hole, which is located in a distant galaxy (星系).The black hole is 500 million trillion km away and was photographed by a network of eight telescopes across the world. It was captured by the Event Horizon Telescope (EHT).

    The announcement was made in Washington, Brussels, Santiago, Shanghai, Taipei and Tokyo. Details have been published today in Astrophysical Journal Letters.

    Prof Heino Falckc, of Radboud University in the Netherlands, who suggested the experiment, told BBC News that the black hole was found in a galaxy called M87. "What we see is larger than the size of our entire Solar System," he said. "It has a mass 6.5 billion times that of the Sun. And it is one of the heaviest black holes that we think exists. It is an absolute monster, the heavyweight champion of black holes in the Universe."

    The image shows an intensely bright "ring of fire", as Prof Falckc describes it, surrounding a perfectly circular dark hole. The bright halo is caused by very heated gas falling into the hole. The light is brighter than all the billions of other stars in the galaxy combined - which is why it can be seen at such distance from Earth. The edge of the dark circle at the center is the point at which the gas enters the black hole, which is an object that has such a large gravitational pull (万有引 力）,not even light can escape.

    "It is remarkable that the image we observe is so similar to that which we get from our theoretical calculations. So far, it looks like Einstein is correct once again." said Dr Ziri Younsi, of University College London -who is part of the EHT cooperation.

    Chinese scientists were involved in the observation through a telescope in Hawaii. They were also highly involved in follow-up data processing and theoretical analysis, said Shen Zhiqiang, head of the Chinese Academy of Sciences' Shanhai Astronomical Observatory and a member of the EHT international team.

    Shanghai and Taipei were selected as two of the cities to hold news conferences, together with Washington, Brussels, Santiago and Tokyo, a recognition of China's contribution.

    "In the fields of astronomy, radio astronomy, and space astrophysics, China has made a significant contribution to this global project," Falcke said.

    Does your local high school have a student newspaper? Only 1 in 8 of New York's public high schools has student newspapers—and many of those are published just a few times a year. A few more are online, which can leave out poorer schools.

    Rebecca Dwarka, an 18-year-old senior who works for her student paper said, "Facebook is the new way of finding out what happened. Nobody wants to actually sit down and read a whole article about it. This makes a 'whole article' sound a little like a long sentence in lonely places."

    I am not nostalgic(怀旧的) about high school student newspapers and never worked for mine. I put out what was then called a personal magazine with a group of friends because we wanted to write about peace, war and rock 'n' roll without school officials warning us not to make jokes about the local officials.

    School newspapers are in decline(衰落) because students now find out what happened on social networking websites. This is a little discouraging because it proves that for millions of Americans, journalism is becoming a do-it-yourself thing. Every citizen can be a reporter.

    When something happens, we look for social media messages. Facebook posts and Tweets have become the means by which citizens and reporters can prove, deny, pass on stories and express opinions without the press' challenging, researching or slowing the message.

    It requires seeing something carefully and it uses an eye for details to help prove a larger view. And even journalism that conveys an opinion tries to be fair. If school newspapers begin to disappear, I hope there are other ways for students to learn that.

I was ever bullied badly when I was in high school. One kid in particular would try to make me feel worse in every way he knew. For example, he would throw stuff at me constantly, hit me on the head, punch me, call me ugly and stupid, make fun of me and, of course tell me he would beat me up if I ever fought back. It was like his daily mission. And it was my daily mission to just get through the day. What could I say? It made my world very small because that was my main focus—just surviving. Everything else fell by the wayside. Unfortunately, that included any form of social life. So not only was my world tiny, but it was very lonely.

    Looking back to that time, which was about 11 years ago, my biggest mistake was not bringing anyone into that world of mine. I was too proud and embarrassed to get help. I would rather not face the fact that I needed help because in my mind, that would mean that the bully had won. It would also mean that I was weak.

Let me just say this—-bullying someone is a weak choice. The only reason why they come after you is that they don't think you will do anything about it. Does that make anyone strong? Absolutely not. Be stronger. Reach out to a parent, a teacher or a friend for help. Simply admit that you are struggling and need help.

    You can put it like this: Somebody who is weak and trying to build himself or herself up has chosen to do that by putting me down. The only reason why they are doing it is that I am nice and I haven't done anything about it yet. Well, I am through putting up with this. I have basic human rights that they are trying to take away to feel better and that is just not OK. How do I handle this the right way? I don't want the pain cycle to continue and I don't want to become someone I don't want to be.

I will close by saying this—-I am not just surviving. I am just enjoying my life. I graduated from college with honors, by the way. You don't have to wait to live. Do something today.

A Dream Chaser in a Wheelchair

    Since the age of three, Chelsie Hill had dreamed of becoming a dancer. That ambition nearly ended in 2010 when Hill was in a car accident, which put the 17- year-old high school senior in hospital for 51 days and left her paralyzed from the waist down. For most people, that would have destroyed any hope of a dancing career. But for Hill, it was the beginning. Far from being a barrier, her wheelchair encouraged her to fight. "I want to prove to everyone including myself that I'm still normal," she said, "whatever normal means."

    Normal for her meant dancing, so Hill did it in her wheelchair alongside her nondisabled high school dance team. Half of her body was taken away from her, so she had to move it with her hands. It took much learning and patience.

    After graduation from high school, Hill wanted to expand her dance network to include women like her. She met people online who were fighting for the dream of dancing against various spinal(脊椎的)injuries, and invited them to dance with her. To reach more people in a larger city, Hill moved to Los Angeles in 2014 and formed a team of dancers with disabilities she called the Rollettes.

    Every year Hill holds a dance camp called the Rollettes Experience for wheelchair users to help them bring out their acting talent. In 2019, 173 participants from ten countries attended. For many, it was the first time they'd felt they belonged. Edna Serrano said that being part of the Rollettes team gave her the courage to get behind the wheel of a car. "I didn't know I could do so many things that my fellow teammates had taught me." she said. "I didn't know I could be sexy. It's so powerful to have my teammates in my life, because they're my teachers. I have more confidence."

    Chelsie Hill attained what many of us never will: her childhood dream. She has been chasing her dream in the wheelchair. She's a dancer. The Rollettes have helped her find something else just as fulfilling.