Twelve years ago, I arrived in Central Florida from Puerto Rico. I had heard of a job opportunity and decided to pursue it. But it never became a reality. I quickly learned that being alone without resources in an unfamiliar city was not a comfortable situation to be in.

    Once my limited funds ran out I became homeless and spent a year and a half living on the streets of Orlando. Apart from feeling not being noticed and missing my family, I had to face another challenge—hunger.

    For the first time in my life, I, as a foreign man, who had lived my life in the relative comfort of the middle class, understood the desperation someone feels when they don't get enough to eat. I clearly remembered having run a distance of more than 7 miles on many occasions just to make it to a local feeding program before they closed at 7 pm.

    Once the need for food was met, the next challenge would arise—where to find a place to sleep for the night. Fortunately, local programs like the Coalition for the Homeless, Second Harvest Food Bank and the Wayne Densch Center were an important part of my ability to survive my painful experience.

    With the assistance of these programs, I was accepted by a college scholarship program through the Coalition and obtained two degrees from Valencia.

    My experience has helped me understand that devoting my life to helping others offers lasting rewards. Today, I am employed as Childhood Hunger Programs Manager at Second Harvest Food Bank and oversee the summer feeding, Hi-Five Kids Pack, and Kids Café programs. I am so proud to be able to distribute food resources to those wonderful programs and help hundreds more like me.

    A recent study led by researchers from the National University of Singapore (NUS) has found a clear link between the color of a taxi and its accident rate. An analysis of 36 months of detailed taxi, driver and accident data from two fleets of yellow and blue taxis in Singapore suggested that yellow taxis have fewer accidents than blue taxis. The higher visibility (能见度)of yellow makes it easier for drivers to avoid getting into accidents with yellow taxis, leading to a lower accident rate.

    The study was led by Prof Ho. To test whether there was a causal relationship between the color of a taxi and the number of accidents the taxi had, the research team analysed data collected by the largest taxi company in Singapore. The researchers found that yellow taxis have about 6.1 fewer accidents per 1,000 taxis per month.

    The researchers also studied the economic effect of changing the color of the entire fleet of taxis to yellow. The Singapore taxi company involved in the study owns about 16,700 taxis in a ratio(比例) of one yellow to three blue taxis. If a commercial decision is made to switch from blue to yellow taxis, 76.6 fewer accidents would occur per month or 917 fewer accidents per year. Assuming an average repair cost of $1,000 per car and a downtime of six days, switching the color of all taxis to yellow could produce an annual savings of $2 million.

    "We are eager to continue to validate(证实) the findings of our study by looking at the use of yellow in other types of public transport, such as school buses. For instance, we hope to compare the accident rates of yellow school buses against other colors to find out if yellow is indeed a safer color for school buses. Besides, we are also interested to look at private-hire vehicles and do a comparison of the accident rates of vehicles that are of different colors," explained Prof Ho.

    When Sir Ector saw Arthur pulled the sword out of the stone and then pushed it back, he rubbed his eyes. "I can't believe it!" he cried. Then he fell on his knees before Arthur. "Father, please do not kneel before me. Tell me what you mean!" Arthur said with great confusion.

    "Listen, then," said Sir Ector. "Years ago the wise magician, Merlin, carried a baby in his arms. That baby was you. Merlin told me to bring you up as my own son. Now I can guess. You must be the late king—King Uther's son. Who else could have pulled out the sword? Arthur, we must let all England know you are qualified to be the new king."

    "I would rather be your son than be a king!" cried Arthur.

    "On Christmas the Bishop (主教) will give everyone a chance to pull the sword. You must take your turn and show everyone that you are the only person who can pull the sword out."

    On Christmas Day the great crowd of knights (骑士) and lords gathered before the church. They pulled and pushed, but no one could make the sword move.

    Down the street came Merlin. Behind him came Sir Ector with Arthur. "Who are these men?" asked the Bishop. "Here is one who will try the sword," said Merlin. He laid his hand on Arthur's shoulder. "Here, lords of England, is the true son of King Uther!" Arthur stepped upon the stone and laid his hand on the sword. Smoothly and easily he pulled it out. He held it high so all could see.

    So Arthur became King of all England. Some of the lords did not want him, and he had to fight them. As the years went by, he became stronger and greater. Knights came from all lands to be in his court. At Camelot Arthur started the famous Knights of the Round Table. These were the greatest of all the knights. They made their names famous for all time.

    Do you want to do some volunteer work while exploring Africa? Then join in our 21-Day Flagship Program. Step onto the flat, sandy land of Ghana, and you'll immediately hear the laughter of children everywhere. This laughter will be the constant of your trip and a steady source of energy while you volunteer among one of Africa s kind communities.

    Community Service

    Volunteer in primary schools, working with children of different ages to help improve their English skills, tutor those who might be falling behind and contribute to each school's needs, including making improvements to the facilities. Split your time between teaching and campus refurbishment (翻修) projects to serve every aspect of the school, and learn all about education in Ghana.

    Hands-on Learning

    Participate in workshops such as batik cloth dyeing (蜡染), drumming, dancing and crash courses in the native language, Ewe or Krobo. You'll be given a Ghanaian name by the local chief of your village, and visit a seamstress (女裁缝) to have custom clothing made out of colorful fabrics you purchase. On the 21-Day Flagship Program, you'll hear about the nation's history as a center of the slave trade, and visit Fort Prinzenstein to truly understand the weight of this topic.

    Adventure

    You'll also experience the natural surroundings of Ghana with a beautiful waterfall hike: On your 21-Day Flagship Program, go on a two-night trip where you'll get to visit a monkey shelter.

    Lodging

    Global Leadership Adventures (GLA) operates two Home Bases for the 21-day program. Both are located outside of the capital city of Accra in rural village settings. Accommodations are basic, but clean and safe. Students sleep in rooms with roommates, and have access to shared bathrooms with cold-water showers.

    Dates

    June 26-July 16, 2019

    July 9-July 29, 2019

    July 20-August9, 2019

    Duration: 21 days

    Tuition: $5,399

    Community Service Hours: 60

    For more information, please call 1-858-771-0645 or send an email to info@experiencegla.com.

Discovering the beauty of the science and maths that shape our everyday lives, an experience in Wonderlab will fuel your imagination and inspire you to see the world around you in new and exciting ways. Come and enjoy yourself!

What to see

Spread across seven different zones, there're loads of opportunities to get hands on with real scientific phenomena. Observe live experiments at our Chemistry Bar, see lightning strike before your eyes, play with forces on giant slides or travel through space under a canopy (苍穹)of stars. You can also take part in explosive science demonstrations led by our talented team of explainers. With 50 mind-blowing wonders of science to enjoy, Wonderlab is an experience unlike any other. Besides, a selection of shows will be performed daily in Wonderlab's beautiful new show space. They are free of charge and last 20 minutes.

Tickets

♦ Day pass:  £ 6 per person.

This ticket gives you day-long access to Wonderlab, perfect whether you're planning a special trip to the Museum or simply passing through London and want to feed your curiosity.

♦ Annual pass:  £ 10 per person.

For less than the price of two visits, give yourself a year packed full of wonder, curiosity and breathtaking experiences.

Opening times

Open seven days a week, 10:00 — 18:00 (last entry 17:15). Wonderlab will be closed on December 24，25 and 26 and will be open as usual from December 27.

During school holidays our opening hours are 10:00 — 19:00 (last entry 18:15). Please note that in peak periods (from midday onwards) we are experiencing long queues due to the gallery's popularity.

A 293-million-mile journey of the NASA Perseverance rover (探测器) to Mars: ended successfully on February 18, 2021, with a picture-perfect landing inside the Jezero Crater. The car-sized, six-wheeled rover, nicknamed Percy is the US space agency's biggest and most advanced explorer to date. Its primary mission is to search for signs of ancient microbial (微生物的) life on Mars.

Landing on Mars is extremely tricky. The Red Planet's gravitational pull causes approaching spacecraft to go faster to high speeds, while its thin atmosphere-just 1 percent that of Earth's-does little to help slow it down as it approaches the surface.

The scientists had to reduce Percy's 12,000 mph speed to a safe landing speed of less than five mph-in just six and a half minutes. The target entry angle also had to be a precise 12 degrees-any steeper, and the spacecraft would burn up; any flatter, and it would get lost in space. It is no wonder that the final approach is often referred to as the "seven minutes of terror. "

Upon attaining a manageable speed, Percy briefly flew over the Martian surface to seek out the perfect landing spot. Its complex map-reading system rapidly scanned the area and matched it with maps in its database to find the best location.

The NASA scientists will spend the next two months testing Percy's scientific instruments. Once ready, the rover will begin to carry out its mission.

"Perseverance is the smartest robot ever made, but confirming that microbial life once existed carries an unusually large burden of proof," said Lori Glaze, director of NASA's Planetary Science Division. "While we'll learn a lot with the great instruments we have aboard the rover, it may very well require the far more well-equipped laboratories and delicate instruments back here on Earth to tell us whether our samples (样本) carry evidence that Mars once harbored life. "