Over the last week, a "poisonous kale（甘蓝菜）" theory has been going widespread after an article warned that the vegetable was associated with a variety of medical conditions. It's time to separate fear from fact on the health benefits of kale.

    As a member of the cabbage family, kale is low in calories and rich in nutrients and minerals, especially vitamin A,C and K. Consumed for thousands of years, it's been a health plus for millions of eaters throughout the world.

    However, numerous web articles have reported on some evidence offered by a medicine researcher. The researcher found that thallium（铊）was detected in a few people who were heavy consumers of kale. Thallium is a heavy metal often found in trace amounts（微量）in soil and minerals. His conclusion was that these medical conditions were connected to the impact that trace amounts of thallium detected in some kale samples had on the body.

    I don't think the conclusion is based on a strict scientific basis. It's essential to point out that the original report was in a web magazine, not a scientific journal which is subject to peer review by other scientists. A scientific review includes a careful evaluation of how the findings and conclusions were made. Certain factors are critical before an evidence-based conclusion can be made, such as: how many people were in a study; how well controlled were other factors; how much kale was consumed and for how long; how much thallium was in the kale.

    It is a fact that kale and other vegetables can absorb thallium from the soil. But the ability for a plant to absorb traces of a chemical does not automatically make it harmful to your health. And even finding measurable amounts of thallium in someone's body doesn't imply that the thallium is causing an ill health effect, according to the CDC.

    But we can still learn a lesson from this. Plants grow in soil. Growers must continue to be careful in monitoring the quality of their soil. And what about consumers? Eat your kale—and include lots of other colorful fruits and vegetables. As with all things in nature, variety is key for good health.

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    When I left my bag on a train, I lost my most precious possession, a small framed photograph of my great grandparents, Emily and Gordon Baker. The frame was made of silver, with an elegant flower design in one corner. The photograph was taken in March 1939 0n their wedding day. Emily looked very happy, and Gordon looked rather a larmed.  A few months later, he was killed in action in North Africa. I received the photograph when my aunt Mabel died.

    I'm a student at Edinburgh University and I live in an old Edwardian house.  At the end of last term, I packed a large bag and a small bag and set off for London, where I was planning to catch the Eurostar train to Paris. Minutes after getting off the train at Kings Cross Station, I realized that I'd left the small bag in the overhead luggage rack. I ran back to the train, but it had already left the platform. www..com

    This all happened several months ago, and I had become resigned to the loss of my most precious possession. then last week, something extraordinary happened. I logged onto the site ~ eBay and looked for a silver photo frame and I found it ! The photo of my great grandparents was on eBay !

    I called the person who was advertising it.   He was a little suspicious(怀疑 )  at first, and told me that he had bought it from a stall at an antique market. After we talked for a while, he asked if there was any way I could prove it was mine. All I could think of was that the photo was taken in March 1939. He opened the frame and made sure that this date was written by hand on the back of the photograph.

    “It's definitely yours. " he said.  "Come and get it ! "

    Did you know that the color of uniforms can influence the performance of an athlete? It may sound strange, but a study suggests this might be true.

    Two British scientists studied the results of four sports in the 2004 Athens Olympic Games where the athletes had been given either a red or a blue uniform. They discovered that when there was a big difference in the score, color had no influence on the result. But if it was a close match, the athlete in a red uniform was more likely to win. Then they looked at the uniforms of the soccer teams at the Euro 2004 tournament. Again, teams wearing red won more games.

    The two scientists got their idea from earlier studies of wild animals. It had been discovered that when a male show red on its body, it sends a signal of its power and strength. For example, in many kinds of monkey, the more the male shows off its red scare, the more females it can attract

    Based on this fact, the British scientists thought that the idea might work for humans, too. According to them, when an athlete sees a competitor in a red uniform, he gets a feeling that his competitor could be stronger than him. And that kind of feeling may have a bad influence on the player's performance in the actual game.

    Although the idea is Interesting, most people don't accept that color signals in the animals world can really be useful to humans in sports. They think that it is unreasonable to develop an Idea based on such a small number of examples. Much more research has to be done to prove the influence of uniform colors on the performance of athletes.

    On a clear night, you can see a sky paced with stars. But you can't see planets orbiting any of these stars, even with the strongest Earth—based telescopes. Astronomers reported that they discovered seven Earth—sized planets orbiting a nearby star called TRAPPIST – 1 in February. They had to rely on indirect evidence to tell them that the planets are there. By doing some math, they figured out the number of planets and the distance of their orbits.

    TRAPPIST – 1 is a red dwarf （红矮星）, much smaller than our sun, but larger than Jupiter (木星). If the sun were the size of a basketball, TRAPPIST – 1would be the size of a gold ball. This star is one of our closest neighbors, just like the moon to the earth in space.

    When astronomers using Earth-based telescopes to study TRAPPIST – 1,they noticed that every once in a while, it became slightly dim（昏暗）. They decided that a planet must be passing in front of the star, blocking part of the light. This dimming would come and go as the planet orbited the star, passing alternately (交替地) behind and in front of the star regularly.

    By making careful observations, astronomers expected to get a rough idea of the planet's size from the pattern of dimming light. But the light level changed often and not at evenly spaced (均匀间隔的) times. The astronomers had to conclude they were looking at more than one planet! To get additional data, NASA's spritzer Space Telescope measured TRAPPIST –1's brightness nearly continuously for 20 days, catching 34 crossings of planets in front of the star. Sorting through the mess of data, the astronomers found that the innermost planet completes its orbit in 1.5 Earth days, while the outermost planet takes 20 days. Once you know how long it takes each planet to complete an orbit, you can work out how far it is from the star compared with the other planets.

    The TRAPPIST – 1 planets are not alone. So far, astronomers have found more than 3,400 planets that orbit other stars.

When David Carter started to study art at The University of Texas (UT) at Austin in 1971, he had big dreams of becoming an artist or a writer. But his study came to a stop at 23 after he hurt his hand in an unpleasant event. He developed schizophrenia(精神分裂症) later and spent many years without a home.

Carter liked to spend time around UT, because he dreamt of being able to continue his study in the university and becoming a writer. After running into Carter many times, UT student Ryan Chandler decided to interview him for a project for the Daily Texan, the student newspaper of UT.

"I interviewed him on Austin's homeless problems. After I heard his story, we kept in touch and really became friends. I learned he wanted to get back to UT, so I decided to help him," said Chandler. "He had got 87 hours, very close to a degree. Now, with changing degree requirements, he only has 64 hours to go."

With the help of Chandler, who worked with the university office, Carter was assigned an adviser by UT's College of Fine Arts. "It' s the greatest gift I've ever received," Carter said. "He did what had to be done to get me back to school, and I couldn't have done it without him"

After seeing a magazine article about Carter, a UT schoolmate decided to pay his tuition fees (学费)without telling Chandler his name.

Doug Dempster, dean of the College of Fine Arts, said in a statement, "David Carter's decision to complete his degree is a testament (证明) to finishing well what was started, and stopped, even many years earlier. We welcome him back as we do many students each year whose education could not be completed easily. We're going to help him through his remaining course work."

Napa Valley is home to some of California's most beautiful hiking trails. Whether you're a seasoned hiker or a beginner, these trails are perfect for a day trip.

Robert Louis Stevenson State Park

Named after the famous author who spent his honeymoon in the area, it offers some of the most scenic hiking trails in Napa Valley. The park features over 5 miles of hiking trails, catering to hikers of all skill levels. You can even see the San Francisco Bay on a clear day.

Skyline Wilderness Park

It is a popular hiking destination in Napa Valley, featuring over 25 miles of hiking trails that offer magnificent views of the valley. On a clear day, you can even see the Golden Gate Bridge. The park is also home to a variety of wildlife, including deer, coyotes and mountain lions.

Westwood Hills Park

It is a hidden gem in Napa Valley. The park boasts over 4 miles of hiking trails, ranging from easy to difficult, making them ideal for a day trip. A wide range of wildlife, including deer and wild turkeys, also lives in this area.

Bothe-Napa Valley State Park

The park is located in the heart of the beautiful Napa Valley wine country and has over 10 miles of trails. It is a paradise for outdoor enthusiasts. It offers easy access to swimming areas and picnic spots. And if you can't get enough of the outdoor activities here, there is a camping site that can be booked for overnight stays.