Mail lay scattered across the kitchen table. I couldn't put off sorting through it any longer. I checked the envelopes, putting aside the ones addressed to my husband.

    It had been over three years since Bob had died. To friends and family it looked like I had moved past the worst of my sorrow. I took care of my house, socialized and kept up with community. On the outside everything appeared to be normal. But inside I was anything but I worried I would never get better, never be myself again. They say sorrow has no set time limit, but I was so tired of feeling empty and hopeless. My sorrow was sharp and fresh as ever. It was like a wall of pressure in my chest, pressing my heart.

    I picked up a piece of Bob's mail and held it out to tear in half, but stopped myself from cutting up the envelope. The letter was from an organization that funded a Haitian orphanage called My Father's House. Its founder, Carol Hawthorne, had given a presentation at our church. Bob and I had donated, and Bob ended up on the mailing list to receive the newsletter (通讯) with updates on the children.

    I hadn't read one since Bob died. But just three months before, in January 2012, the country had been hit by a terrible earthquake. In my depressed state, it hadn't even occurred to me to wonder whether the orphanage had survived. I opened the newsletter and was surprised to find out that My Father's House was still standing. Of course now it was more crowded than ever. At the bottom of the page was an announcement about an upcoming trip to visit the orphanage in person. “I should go.” The thought wouldn't leave me. I contacted Carol Hawthorne.“What would I do if I go?” I asked.“Build houses?”

    “The Haitian people there are eager to work and they know what they're doing,” said Carol. “What they need are raw materials, and we provide them. We also visit with the children. We go to clinics and schools, pass out supplies. You'll be very busy, I promise!” I reserved a seat but didn't mention it to any of my friends. Just a few weeks later, I was at the airport with seven strangers, waiting to board a plane to Haiti. Even after takeoff I wasn't really sure of what I was doing.

    In Haiti we were met by Pastor Ronald Lefranc, the director of My Father's House. We piled into an old school bus and drove over uneven roads full of stones and mud. We passed women shaking under the weight of huge water buckets balanced on their heads. Piles of rubbish scattered across the landscape, and the land was covered with broken tents. Finally we pulled up to the orphanage. A crowd of children—52 in all—rushed up to greet us. I couldn't understand the words of the song they sang in Creole, but with the smiles on their faces I didn't need to. Each child planted a big kiss on my cheek.

    Carol and Pastor Ronald led us into the main building. “What are those over there?” I asked, pointing to a collection of thin tents. “Is there not enough room in the building for all the children?”

    “We have the room,” said Pastor Ronald. “But many of these children came here after the earthquake. They still don't feel safe sleeping under a roof.”

    There was no sign of fear in the playroom inside. I played dolls and other games. Children I'd just met presented me with pictures they'd drawn and letters written in Creole. In the evening the children gathered in the dining room. They took turns reading aloud and then they all joined in song. The words were strange, but the tune sounded familiar.

    They'd lost so much, yet were so joyful. In the evening the children gathered in the dining room. One of the older children stood up to speak and then they all joined in song. The words were strange, but the tune sounded familiar. The children settled down. In the silence, a quiet noise began.

    My grandfather came from Hungary and was the only one in his family who settled down in the United States. The rest of his family remained in Europe. When World War I broke out, he seemed to have become another man, downhearted. Such obvious change was not born out of concern for his welfare, but out of fear: if his only son, my uncle, had to go to war, it would be cousin fighting against cousin.

    One day in 1918, my Uncle Milton received his draft notice. My grandparents were very upset. But my mother, at the age of 10, felt on top of the world about her soldier brother going off of war. Realizing how he was regarded by his little sister and all of her friends, my uncle bought them all service pins, which meant that they had a loved one in the service. All the little girls were delighted.

    The moment came when my uncle and the other soldiers, without any training but all in uniforms, boarded the train. “The band played and the crowd cheered. Although no one noticed, I'm sure my grandmother had a tear in her eye for the only son. The train slowly pulled out, but not about a thousand yards when it suddenly paused. Everyone stared in wonder as the train slowly returned to the station. There was a dead silence before the doors opened and the men started to step out. Someone shouted, “The war is over!”For a moment, nobody moved, but then the people heard someone bark orders at the soldiers. The men lined up in two lines, walked down the steps, and with the band playing, marched down the street, as returning heroes, to be welcomed home. My mother said it was a great day, but she was just a little disappointed that it didn't last a tiny bit longer.

    It used to be mostly the military that used small, unpiloted aircraft, called “drones.” The little planes were very costly. But as they have dropped in price more people have begun to use them. Rescue workers and farmers are among the new users. Moviemakers are using drones to film from the sky. Historians use them when they explore ancient buildings. Rescue workers use them to look for people. And now farmers are using them to watch over their crops.

    Romain Faroux is a French businessman who starts companies. His father was a farmer. He believed drones could help farmers. He helped create a company that developed a small drone that could be controlled by people on the ground. They called it “Agridrone.” It uses a special “optical sensor” to examine crops. He says the technology used is similar to that used by smartphones-except it has wings.

    A computer program directs the drone to fly over the crops. The sensor on the drone records four different-colored “bands” of sunlight that are reflected off the crops.

    Jean-Baptiste Bruggeman is a farmer. He says the drone flies over his crops at different times of the season. He says this provides a lot of information about his crops. He says the drone pictures show him the exact amount of fertilizer the crops need. He says it also shows exactly where the fertilizer is needed. Some areas of a field may need more than others.

    As a result, Mr. Bruggeman says there is reduced nitrogen from the fertilizer after the harvest. This helps nature. Romain Faroux says farmers use information gathered by the Agridrone to place fertilizer only in areas where it was needed. Before they used the drones, farmers would put the same amount of fertilizer everywhere.

    Drones also save time because farmers can examine up to three hectares in about a minute.

    People with bigger brains tend to score higher on standardized tests of intelligence, according to new study findings.

    However, the study author Dr. Michael A.McDaniel of the Virginia Commonwealth University in Richmond emphasized that these findings represent a general trend, and people with small heads should not automatically believe they are less intelligent. For instance, Albert Einstein's brain was "not particularly large", McDaniel noted." There's some relationship between brain size and intelligence on the average, but there's plenty of room for exceptions," he said.

    Interest in the relationship between brain size and intelligence grew in the1830s, when German anatomist(解剖学家) Frederich Tiedmann wrote that he believed there was "an unquestionable connection between the size of the brain and the mental energy displayed by the individual man". Since that statement, scientists have conducted numerous studies to determine if Tiedmann's assertion was correct. Most studies have looked into the link between head size and intelligence. More recently, however, researchers have published additional studies on brain size and intelligence, measured using MRI scan(核磁共振成像扫描).

    For his study, McDaniel analyzed more than 20 studies that looked into the relationship between brain size and intelligence in a total of 1,530 people. The studies showed that on the average, people with larger brain volume tended to be more intelligent. The relationship between brain volume and intelligence was stronger in women than men, and in adults than in children. McDaniel notes in the journal Intelligence.

    McDaniel is not sure why the relationship was stronger for adults and women. "Other research has shown that women, on the average, tend to have smaller brains than men, but score just as well—if not higher—in tests of intelligence," he said.

    McDaniel insisted that the relationship between brain size and intelligence is not a "perfect" one. "One can certainly find lots of examples of smaller-sized people who are highly intelligent," he said, "But, on the average, the relationship holds."

    Good health is the most valuable thing in the world. When you've got it, you never think about it. When you haven't got it, you think about it all the time. Our biggest enemies are not terrible diseases and so on. We are our own biggest enemies because we sometimes destroy our own good health. Some of us eat too much, drink too much and smoke too much. And though our reason tells us we should control ourselves, we find it difficult. The fact is that most human beings need stimulation (刺激). Who doesn't enjoy a drink after a busy day? Only a smoker knows the pleasure of a cigarette with a cup of coffee.

    The danger is when these innocent pleasures run our lives and so destroy our health. When you find yourself eating between meals or eating too much rich food, when you can only keep yourself going by taking frequent drinks or by smoking one cigarette after another, then it's time to stop and think what you might be doing to yourself. The funny thing is that when we don't control ourselves, simple pleasures are no longer simple pleasures.

    All right, I know what you're thinking. You're probably saying, “It's easy to say, but I can't help myself. I need that extra bit of food, that extra drink, that extra cigarette. Life has so many pleasures that I can't do without them.” But I'm saying you can help yourself. Not only that, you must help yourself. Because if you don't help yourself, no one else can. So be your own best friend.

    The Largest World Fairs of All Time

    New York World Fair — New York, 1939

    The 1939 New York World Fair was the largest exposition (博览会) in US history with visitors over 14 million. The Fair was planned during the Great Depression and was aimed at relieving the city from economic depression by attracting foreign investment. Major inventions to emerge (出现) at the New York World Fair included nylon fabric, a streamlined pencil sharpener, and a futuristic car city imagined by General Moiors.

    Exposition liniverselle — Paris, 1900

    The Exposition Universelle was one of the earliest expositions to feature multiple countries with France inviting various countries to display their technological advancements and cultural heritage. Exposition Universelle was the birthplace of many inventions that we enjoy today including escalators (自动扶梯) and talking films.

    Expo' 70 — Osaka, Japan

    Expo' 70 was the biggest exposition of the 20th century and the second largest in history. Expo 70 had a record attendance of over 64 million visitors, a 40-year record that would not be broken until Expo 2010 in Shanghai. Notable exhibitions included a large piece of moon rock that was brought back from the Apollo 12 mission.

    Expo 2010 — Shanghai. China

    Expo 2010 goes down as the largest fair in history, having attracted 73 million people. It also had the highest international participation of any exposition in the world with 246 countries participating. The opening ceremony featured the biggest LED screen in the world as well as one of the biggest fireworks displays in history.