Most people know precious gemstones (宝石) by their appearances. An emerald flashes deep green, a ruby seems to hold a red fire inside, and a diamond shines like a star. It's more difficult to tell where the gem was mined, since a diamond from Australia or Arkansas may appear the same to one from the Democratic Republic of the Congo. However, recently, a team of scientists has found a way to identify a gemstone's origin.

    Beneath the surface of a gemstone, on the tiny level of atoms and molecules（分子）, lie clues (线索) to its origin. At this year's meeting of the Geological Society of America in Minneapolis, Catherine McManus reported on a technique that uses lasers (激光) to clarify these clues and identify a stone's homeland. McManus directs scientific research at Materialytics, in Killeen, Texas. The company is developing the technique. “With enough data, we could identify which country, which mining place, even the individual mine a gemstone comes from,” McManus told Science News.

    Some gemstones, including many diamonds, come from war-torn countries. Sales of those “blood minerals” may encourage violent civil wars where innocent people are injured or killed. In an effort to reduce the trade in blood minerals, the U.S. government passed law in July 2010 that requires companies that sell gemstones to determine the origins of their stones.

    To figure out where gemstones come from, McManus and her team focus a powerful laser on a small sample of the gemstone. The technique is called laser-induced breakdown spectroscopy. Just as heat can turn ice into water or water into steam, energy from the laser changes the state of matter of the stone. The laser changes a miniscule part of the gemstone into plasma, a gas state of matter in which tiny particles（微粒）called electrons separate from atoms.

    The plasma, which is superhot, produces a light pattern. (The science of analyzing this kind of light pattern is called spectroscopy.) Different elements produce different patterns, but McManus and her team say that gemstones from the same area produce similar patterns. Materialytics has already collected patterns from thousands of gemstones, including more than 200 from diamonds. They can compare the light pattern from an unknown gemstone to patterns they do know and look for a match. The light pattern acts like a signature, telling the researchers the origin of the gemstone.

    In a small test, the laser technique correctly identified the origins of 95 out of every 100 diamonds. For gemstones like emeralds and rubies, the technique proved successful for 98 out of every 100 stones. The scientists need to collect and analyze more samples, including those from war-torn countries, before the tool is ready for commercial use.

    Scientists like Barbara Dutrow, a mineralogist from Louisiana State University in Baton Rouge, find the technique exciting. “This is a basic new tool that could provide a better fingerprint of a material from a particular locality,” she told Science News.

    In the English language there are striking similarities to many of the characteristics present in Spanish, French, and German. So what are the things that make English so difficult for foreign people to learn?

    English doesn't necessarily have more regular consonant(辅音) or vowel(元音) sounds than other languages, but how the stress is placed on some of those consonants or vowels makes it such a difficult language for learners. There are hard and soft consonants like “c” taking on a “k” sound or an “s” sound depending upon the situation. There are silent letters in some words and then some consonants that take on an entirely different sound ( like “th” ) when combined. The changes in the pronunciation of words make English much more difficult to learn.

    Another thing that makes English difficult to learn has to do with verb tense. Some languages have very limited changes in verb tense, sometimes just present and past, which makes it relatively simple to grasp. English, on the other hand, is a bit more difficult in this area. For example, in different situations it may be proper to use any of the following tenses: present, past, future, past perfect or present perfect. The verb “choose” can be used in the following forms depending on tense: choose, chose or chosen. This can be very difficult for a foreigner to grasp.

    Slang(俚语) is more widely used in American English than proper grammar. In the US just knowing the language as it's generally taught isn't enough. In every single region or even close neighborhoods, the same slang terms make an almost entirely different language. In some areas there are repeatedly used terms that wouldn't even be found in the Webster's Dictionary. They are created by locals and only locals understand them. This can make it very difficult for someone not familiar with the language to get used to it, especially if they don't remain in one area for a very long period.

    People aren't walking any more—if they can figure out a way to avoid it.

    I felt superior about this matter until the other day I took my car to mail a small parcel. The journey is a matter of 281 steps. But I used the car. And I wasn't in any hurry, either, I had merely become one more victim of a national sickness: motorosis.

    It is an illness to which I had thought myself immune（免疫的）, for I was bred in the tradition of going to places on my own two legs. At that time, we regarded 25 miles as good day's walk and the ability to cover such a distance in ten hours as sign of strength and skill. It did not occur to us that walking was a hardship. And the effect was lasting. When I was 45 years old I raced—and beat—a teenage football player the 168 steps up the Stature of Liberty.

    Such enterprises today are regarded by many middle-aged persons as bad for the heart. But a well-known British physician, Sir Adolphe Abrhams, pointed out recently that hearts and bodies need proper exercises. A person who avoids exercise is more likely to have illnesses than one who exercises regularly. And walking is an ideal form of exercise—the most familiar and natural of all.

    It was Henry Thoreau who showed mankind the richness of going on foot. The man walking can learn the trees, flower, insects, birds and animals, the significance of seasons, the very feel of himself as a living creature in a living world, He cannot learn in a car.

    The car is a convenient means of transport, but we have made it our way of life. Many people don't dare to approach Nature any more; to them the world they were born to enjoy is all threat.To them security is a steel river thundering on a concrete road. And much of their thinking takes place while waiting for the traffic light to turn green.

    I say that the green of forests is the mind's best light. And none but the man on foot can evaluate what is basic and everlasting.

    When we're in need, we always turn to our parents for help. But would you like them to hear the conversations you have with your friends on the school playground or lunch queue? Social networking sites have become extensions (延伸) of the school hallways, so would you add your parents as “friends” and allow them to view your online activities and conversations with friends?

    In the past the generation gap included a technology gap, where children were up to date with latest technology and parents were left behind, content to continue their day to day lives as they always had because they had no need to know more about technology. However, more and more parents are beginning to realize just how important social networks are in their lives. This realization has given many parents the motivation to educate themselves about social networking sites.

    These days many people are attracted to social networking sites because they can choose who they have around them; there's also a certain amount of control over privacy that we don't get in real life. Sometimes we feel that privacy is violated (侵犯）when we must accept a “friend” request from a parent or family member.

    It's a difficult choice whether or not to allow a parent to become a part of our online lives. On the one hand we don't want to “reject” their request because that might hurt their feelings or make them feel you have something to hide. On the other hand if you do accept, then you could have a sense of being watched and no longer feel free to comment or communicate the way you did before.

    A recent survey suggested that parents shouldn't take it personally if their child ignores their request: “When a teen ignores a parent's friend request, it doesn't necessarily mean that they are hiding something, but it could mean that this is one part of their life where they want to be independent.”

    Perhaps talking with parents and giving explanations would help soften the blow if you do choose not to add them to your friends list.

The Grand Palace

    If there is one must-see sight without which no visit to Bangkok would be complete, it's the spectacular Grand Palace, undoubtedly the city's most famous landmark. Built in 1782 and for 150 years the home of the Thai King, the Royal court and the administrative seat of government, the Grand Palace of Bangkok continues to have visitors in awe of its beautiful architecture and complicated details, which is a proud salute (致敬) to the creativity and craftsmanship of Thai people. Within its walls were also the Thai war ministry, the state departments, and even the mint (铸币厂). Today, the complex remains the spiritual heart of the Thai Kingdom.

    Important Notes about the Grand Palace

    A strict dress code applies. The Grand Palace with the Temple of the Emerald Buddha is Thailand's most sacred site. Visitors must be properly dressed before being allowed entry to the temple. Men must wear long pants and shirts with sleeves (no lank lops). If you're wearing sandals or flip-flops you must wear socks, in other words, no bare feet. Women must be similarly modestly dressed. No see-through clothes, bare shoulders, etc. If you show up at the front gate improperly dressed, there is a booth near the entrance that can provide clothes to cover you up properly (a deposit is required).

Opening Hours: Daily 8:30-15:30

    Location: Na Phra Lan Road, Old City (Rattanakosin)

    Price Range: Tickets sold from 8:30-15:30 and cost 500 baht! One ticket includes entry to Vimanmek Palace and Abhisek Dusit Throne Hall.

    The City of Christchurch, New Zealand was struck by a 7.1­magnitude earthquake on the early morning of Saturday, September 4, 2010.

    No tsunami alert was reported. The country's army troops were on standby to assist victims and disaster recovery operation. New Zealand's Prime Minister John Key, flew to the affected area to inspect and assess the situation of the damaged city. The Prime Minister said that the full assessment of the damages would possibly take months to know the severity of damages. Based from his assessment on what he saw in the area, it could cost at least 2 billion New Zealand dollars or US$1.4 billion for reconstruction.

    "An absolute miracle that no one died," Prime Minister John Key said. Two were seriously injured from this quake and thousands of local residents were awakened after being shaken at 4:35 a.m. of that Saturday.

    There were people trapped inside the damaged buildings but fortunately none were reported dead from the rubble of the damaged buildings.

    "We're all feeling scared—we've just had some significant aftershocks," a survivor told TV One News. "Tonight we're just people in the face of a massive natural disaster, trying to help each other and we're grateful we haven't lost a life."

    GNS Science reported 29 aftershocks within the 14 hours after the quake, with strength from magnitude 3.7 to 5.4.

    New Zealand is no stranger to earthquakes. The country experiences more than 14,000 earthquakes a year—but only about 150 are felt by people.

    "Many buildings here were built with earthquake protection measures. However, in most cities in developing countries, people build how they want to and there're no building controls to force them to build to a higher standard that's safe," Andrew Charleson, an architecture professor at Victoria University of Wellington told CNN.