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    Have you ever wondered why the roots of the plants always know which way to grow—into the soil but not above it? Some British scientists have recently solved this mystery.    

      It turns out that roots have special hairs that tie them into the soil and help them grow their way past obstacles, a team at the John Inners Center in Norwich reports in the February 29 issue of Journal Science.

    "The key is in the fuzzy(有绒毛的) coat of hairs on the roots of plants," says professor Liam Dolan. "We have found a growth control system that enables these hairs to find their way and to become longer when their path is clear."

    Root hairs explore the soil in much the same way a person would feel their way in the dark. If they come across an obstacle, they make their way around until they can continue growing in an opening. I the meantime, the plant is held in place as the hairs grip the soil.

    The hairs are guided by a clever chemical trick. A protein(蛋白质) at the tip of the root hairs called RHD2 helps them to take calcium(钙) from the soil. Calcium makes the hairs grow, and produce more RHD2, and take more calcium.

    But when an obstacle blocks the hair's path, or the hair reaches the surface of the soil, the cycle is broken and growth starts in another direction.

    This system gives plants the flexibility to explore a complex environment and to live in even the most unpromising soils, says Dolan.

    In poor soils such as in parts of Australia and Africa, native plants have adapted by producing enormous numbers of root hairs. A better understanding of this adaptation will allow scientists to develop hairy rooted crops that can grow in unfriendly environments.

    According to Dolan, "Research in the John Inners Center is taking a breeding approach(育种方法) to increase hair length in wheat but it will be some time before new cultivars(栽培变种) are developed."

    Rome, Paris and New York are the world's top fashion cities, all of which have produced some of the top trends, from fashionable skirts to the hottest new shoes. But have you ever wondered about the negative ideas that they have enforced?

    In April 2016, the Advertising Standards Authority (ASA) in Britain banned an ad from Gucci that featured models dancing around and having fun, because they were all extremely skinny. Banning ads due to the models' extreme figures isn't new. The ASA banned an ad in 2015 for the same reason. In France, it has been ruled that models are to provide a doctor's note providing that they are at a healthy weight.

    So what is the healthy weight for models? Twenty years ago, the average fashion model weighed 8% less than the average woman. Today, they weigh 23% less.

    People may think that being at an unhealthy weight will help them gain the benefits that the models do. This provides a standard of beauty, and therefore people who want to achieve those things may attempt to obtain them through unhealthy ways. People may think that they are overweight, due to the images of models¹ thin figures. They see something wrong with their bodies, whether they are overweight or not. This is a key factor in a lowered body image, low self-esteem, depression and possibly even eating disorders.

    I'm not blaming the fashion industry by any means. It's not their fault that many people look up to the models and expect to live a life like theirs. I am glad that the ASA is raising its voices when discussing the growing issue of body images in the fashion industry. By banning photos and videos, speaking out against them and pushing for doctor's notes from the models, it's pushing for the ideas that the traditional fashion industry's body image demands should be changed and something more needs to be questioned.

    Do you still remember your favorite poem from high school or some other important periods in your life？Why is it that decades later it still stands out in your mind？Probably the main reason is that some aspect of that poem resonates (引起共鸣) with you. In the same way, you too as a school leader can touch the hearts of your teachers and students.

    Poetry allows us to experience strong spiritual connections to things around us and to the past. The power that poetry has displayed over time and across cultures actually satisfies this common need of the human heart and soul.

    As one of the oldest art forms, poetry has successfully connected various parts of humanity (人性) from one generation to another. Referring to poetry, Hillyer makes a simple yet meaningful statement, “With this key mankind unlocked his heart.”

    School leaders can find and make use of the value of poetry for themselves, their students and their teachers. Beyond the simple use of poetry, techniques of poetry such as repetitions can be used to take advantage of the power of language to transform communication, create meaning and a culture of care and attention.

    Since schools are mainly about people and relationships, school leaders, like poets, are required to inspire and encourage the human heart. The use of poetry—or even of some techniques of poetry—in school leadership not only helps to improve communication, but also serves to meet the human need for inspiration.

    Here are three best destinations for you to discover in 2018 if you ho heart-stopping adventure, a close-up look at history or the perfect meal.

    Los Cabos, Mexico

    Located at the tip of the Baja Peninsula, the two small colonial(殖民地的) towns of Cabo San Lucas and San Jose del Cabo have become the hottest vacation destinations in Mexico in recent years. With wide, original beaches, lively nightclubs, natural resorts, and a farm-to-table food scene, the oasis(乐园)of Los Cabos is drawing tourists in record numbers. As a result, the hotel scene is booming, with a lot of new developments and repairs completed this year.

Zambia

    Until now, Zambia has had little recognition as one of Africa's great safari(狩猎远征) destinations. Yet experts know it as the birthplace of the walking safari. In South Luangwa National Park, visitors can expect to see more animals than baobab trees, while Liuwa Plain National Park is the setting for the world's second-largest wildebeest(角马) migration, when tens of thousands of the creatures head across the plain from neighboring Angola.

Brussels, Belgium

    Visitors may want to return to the Belgian capital in 2018 to visit two cutting-edge museums. The Millennium Iconoclast Museum of Art opened to show contemporary art from around the world. There's also the Citroen Cultural Centre, which will launch its first exhibition in May. The JAM Hotel with exposed brickwork and concrete beams housed in a former art school, is the perfect place for culture-lovers to stay. don't leave town without experiencing beer culture at youthful breweries(啤酒厂) like Brasserie de la Senne or Brussels Beer Project.

                                                                                       Official Historical Tour of Harvard

    Student-Led Public Walking Tour

    Please note: Due to ongoing construction, our tour schedule will be limited. Please check our updated tour times on the calendar. In the event of bad weather, please check the calendar or call regarding a scheduled tour time.

    The tour is student-led and includes an outdoor walk(please dress appropriately)through Harvard Yard, providing a history of the university, general information, and a unique view on the students' individual experience. The tour is around one hour long, and completely free of charge. There is no pre—registration for general visitors, and we begin registration for each tour one hour before departure time. Currently we are only able to accommodate groups of up-to 14 people on our free, public tour. If you have a group of 15 or more, reservations are required (please see below).

    Group Tours and Reservations

    Reservations are required for tours of 15 or more people, with an absolute maximum of 125 people. We request 2 weeks' notice to schedule a tour. Please note that we cannot accommodate groups that arrive without a reservation.

    A Self-Guided Walking Tour of Harvard Yard

    If you are interested in touring the campus on your own,you may want a self-guided walking tour. These tour pamphlets(册),offered in nine different languages, can be purchased from our office for a minimal charge.

    You may also download audio files of historical information on each of the buildings in Harvard Yard. These files, together including an Audio Tour, can also be obtained here with a simple click.

    The morning after an evening flight with my then three-year-old daughter, I couldn't wait to get her to school. I was tired from the anger, and her inability to communicate because of her slowed language development.

    As I accompanied her into the car, I felt desperate. Nothing was right with our world. She had been born around the same time the nation was witnessing the birth of another Great Recession(经济萧条). My job and my house had been victims. Then this happened. My child's language delay was identified, but doctors struggled to properly diagnosis her. I felt like we both needed to be rescued.

    I returned that afternoon as disenchanted with the little girl I loved as when I left.

Walking slowly toward the school's playground gate, I found her preschool teacher racing to greet me.

    “You should have seen her today!” His breathy words were supported by excitement.  I didn't interrupt. “See that climber.” He pointed to a piece of wooden playground equipment that looked like a rock wall. I nodded. “Well, every day since she started school. She's tired and failed to make it to the top.” He took a breath. “And today she made it.

    He expressed his joy just like he'd witnessed her conquering (征服) Mount Everest “She cheered and celebrated! I wish I'd recorded it.” His words comforted me. My daughter had conquered her mountain. As she ran toward me, I recognized something I hadn't before. I saw her perseverance. I saw her strength. I saw a hero.

    Everyday greatness celebrates ordinary people who do unusual things in big and small ways, showing courage, kindness, love and selflessness. We encourage you to click these brief accounts and invite you to share your own story in our community.