In the library, I found my way into the “Children's Room.” I sat down on the floor and pulled a few books off the shelf at random. The cover of a book caught my eye. It presented a picture of a beagle. I had recently had a beagle, the first and only animal companion I ever had as a child. He was my secret sharer, but one morning, he was gone, given away to someone who had the space and the money to care for him. I never forgot my beagle.

       There on the book's cover was a beagle which looked identical（相同的） to my dog. I ran my fingers over the picture of the dog on the cover. My eyes ran across the title, Amos, the Beagle with a Plan. Unknowingly, I had read the title. Without opening the book, I borrowed it from the library for the summer.

Under the shade of a bush, I started to read about Amos. I read very, very slowly with difficulty. Though pages were turned slowly, I got the main idea of the story about a dog who, like mine, had been separated from his family and who finally found his way back home. That dog was my dog, and I was the little boy in the book. At the end of the story, my mind continued the final scene of reunion, on and on, until my own lost dog and I were, in my mind, running together.

       My mother's call returned me to the real world. I suddenly realized something: I had read a book, and I had loved reading that book. Everyone knew I could not read. But I had read it. Books could be incredibly wonderful and I was going to read them.

       I never told my mother about my “miraculous” (奇迹般地) experience that summer, but she saw a slow but remarkable improvement in my classroom performance during the next year. And years later, she was proud that her son had read thousands of books, was awarded a PhD in literature, and authored his own books, articles, poetry and fiction. The power of the words has held.

    Recently I and other Red Cross volunteers met a group of victims from Hurricane Katrina. We were there, as mental health professionals, to offer “psychological first aid” and I was struck by the simple healing power of presence. As we walked in the gate to the shelter, we were greeted with a burst of gratitude from the first person we met. I felt appreciated, but also guilty, because I hadn't really done anything yet.

    I first realized the power of presence many years ago when a friend's mother passed away unexpectedly. I received a call saying she had just passed away. I wanted to rush down there immediately, but didn't want to intrude(打扰) on this very personal period of sadness. I was torn about what to do. Another friend with me then said, “Just go. Just be there.” I did, and I will never regret it.

    Since then, I have not hesitated to be in the presence of others. Once I sat at the bedside of a young man suffering from the pain of his AIDS-ralated dying. He was not awake, and obviously unaware of others' presence. However, the atmosphere was by no means solenm. His family, playing guitars and singing, allowed him to be present with them as though he were still fully alive.

    In my life, I am repeatedly struck by the healing power of presence. In it, none of us are truly alone. It not only is something we give to others but also changes me for the better.

    It was Sunday, so Dad and I were at the second-hand goods market, looking for tools, appliances(家用电器), and other things that needed cleaning. Some were broken; others, like silver cups, just needed to be cleaned and polished. It was 1974, and the Depression(经济大萧条) was very serious. Dad worked full-time at a factory, but the money wasn't enough. Dad had tried a second job for a while, but he found it was too hard on the family. One day, he had an excellent idea that set me on a lifelong course of making money to support myself. Standing beside a crowded table at the second-hand goods market, I looked over an ancient manual sewing machine. Someone had changed it to run on electric power. It was much older than Mom's machine, but it looked like it had quality and a long life built into it. "Dad!" I called. "This is a beauty!"

    Dad walked over, pulling a cart full of audio equipment, tools, worn-out appliances, and what appeared to be a block of dull kitchen knife." What have you got, Son?" I described what I saw and what I figured I could do to x the beauty up. Dad paid for my discovery, and we headed home.

    Every day after school I worked on the ancient machine, and every night Dad and I sharpened tools and knives, sanded off rust, polished metal, and replaced missing parts from various items. The next Saturday we headed off, as we did every weekend, to that same market, where we sold the treasures we'd purchased the week before—at a tidy profit. My antique beauty brought in more money than anything else, and Dad let me keep every penny.

    Dad's gone now, but I can never thank him enough. Even if we hadn't needed the extra money Dad and I brought in, I wouldn't have traded those weekends for all the picnics or Little League games in St. Louis—not in a million years.

    After decades of cat-and-mouse between athletes and the word anti-doping agency (WADA), athletes found what they must have believed to be the ultimate (终极的) doping agent: their own blood. To enhance athletic performance with your own blood, you draw your blood and store it in a freezer. Your body compensates by creating more blood. Then, months later, just before a competition, you can re-inject (注射) the old blood for a boost. As the red-blood-cell count goes up, so does an athlete's ability to absorb oxygen. The more oxygen you get with each breath, the more energy your body is able to bum and the better you are able to perform.

    Although the enhancement is small compared to actual drugs, it can be the difference between a gold medal and a silver medal. Best of all, "extra blood" was never something WADA tested for.

    But WADA wasn't going to sit by and be fooled. What it came up with in response might be a solution to stop doping once and for all: an athlete biological passport (ABP). The idea is to record some biological features of an athlete through testing done at regular intervals. The biological passport's partial implementation (实施)—recording blood and steroid levels—began in January 2014.

    When all necessary biological features are finally combined, WADA will no longer need to worry about finding new methods to detect a drug. It will only have to detect (检测) resulting changes in the body. In the case of blood doping, if the athlete's normal red-blood-cell count is, say, 47%, but then is found to be 51% after a competition, cheating may have been involved.

    WADA is confident that the biological passport could even prevent genetic changes—the ultimate, ever-lasting enhancement—which are surely coming next. If an athlete inserts a performance enhancing gene, it will probably leave detectable changes in the body, that would differ from the athlete's feature in the biological passport.

    Solar energy systems/power plants do not produce air pollution, water pollution, or greenhouse gases. Using solar energy can have a positive, indirect effect on the environment, when solar energy replaces or reduces the use of other energy sources that have larger effects on the environment.

    However, some poisonous materials and chemicals are used to make the photovoltaic (光电池的) cells that convert sunlight into electricity. Some solar thermal (保热的) systems use potentially hazardous liquids to transfer heat. Leaks of these materials could be harmful to the environment. U. S. environmental laws regulate the use and settlement of these types of materials.

    As with any type of power plant, large solar power plants can affect the environment near their locations. The placement of the power plant may have long-term effects on the habitats of native plants and animals. Some solar power plant-s may require water for cleaning solar collectors and concentrators or for cooling turbine generators. Using large volumes of ground water or surface water in some dry locations may affect the ecosystems that depend on these water resources. In addition, the beam of concentrated sunlight a solar power tower creates can kill birds and insects that fly into the beam.

    The amount of solar energy that the earth receives each day is many times greater than the total amount of all energy that people consume each day. However, on the surface of the earth, solar energy is a variable and irregular energy source. The amount of sunlight and the intensity of sunlight varies by time of day and location. Weather and climate conditions affect the availability of sunlight daily and on a seasonal basis. The type and size of a solar energy collection and conversion system determines how much of the available solar energy we can convert into useful energy.

    The world's first hydrogen-powered trains have begun running in Germany. They began carrying passengers Monday in Germany's northern Lower Saxony state. The new train will run 100-kilometer trips and can travel up to 140 kilometers an hour.

    A French railroad company called Alstom built the two trains. Team in Germany and France cooperated on the project, which was supported by the German government. The new train model ,called the Coradia ilint, signals the beginning of efforts in Germany and other nations to move away from pollution-producing diesel(柴油) trains.

    The Coradia iLint is designed to run on non-electrified train lines with low levels of noise.

    It uses a process that combines hydrogen and oxygen to produce electrical power. If the system produces more energy than the train needs at that time, it can store the extra energy in batteries. The only emissions (排放物) are water and steam.

    A single tank of hydrogen can run a Coradia iLint train for about 1,000 kilometers. This is very similar to the distance a diesel-powered train can run on with a single tank.

    Hydrogen-powered trains cost more than diesel trains to build. But Alstom officials say the operating costs are much lower. The company plans to provide another 14 Coradia iLint trains to Lower Saxony by 2021.

    The head of railroad operations in the area, Carmen Schwab, praised replacing diesel trains with hydrogen. She said the move was an important first step in using clean-burning technologies to reach climate protection goals.

    Officials say the area's many wind turbines (涡轮机)will produce part of the energy to create the hydrogen to power the trains.

    Alstom says several other European countries have also expressed interest in developing hydrogen train systems. France has already said it wants its first hydrogen train to be operating by 2022.