As we know, DNA testing is very useful for crime fighting. But now crime fighters could have a new tool at hand. Researchers have developed a cutting-edge (前沿的) technique to identify human hair. Their test is quicker than DNA analysis techniques currently used by the police.

    DNA testing is commonly used for identification because DNA is unique to each individual. However, environmental and chemical processes can degrade(降解) DNA, limiting its usefulness over time. Protein (蛋白质) in hair, on the other hand, is more stable than DNA but can also have variations (变异体) that may be unique to the individual.

    “Our analysis process can be used universally, ”says Ms. Huang, “One of our samples even included dyed hair and the test was 100 per cent accurate. The test was able to distinguish East Asians, Caucasians and South Asians.”

    Dr. Beauchemin says she has got in touch with law enforcement agencies about using the new technology. She is also planning to collect more hair samples and continue her research with a goal of finding where exactly in the world hair sample is from, to look for more races and determine specific age.

    “We are in a very similar place with protein-based identification to where DNA testing was during the early days of development,” said chemist Brad Hart. “This method will be a game-changer, and while we've made a lot of progress toward improving it, there are steps to go before this new technique is able to reach its full potential.”

    There was good news last week for people who struggle to get eight hours of sleep a night: they may not need so much shut-eye after all.

    Researchers from UCLA and elsewhere looked at sleep habits of remote hunter-gatherers in Tanzania, Namibia and Bolivia — groups with pre-industrial lifestyles whose sleep patterns are believed to reflect those of ancient humans. The researchers found that, on average, members of each group sleep a bit less than six and a half hours a night.

    The study, published in the academic journal Current Biology, indicates that “natural” sleep is less than eight hours a night and that modern society's numerous electronic distractions (分心) aren't necessarily to blame for people getting just six or seven hours of sleep.

    “The story that often gets out is that if you sleep for less than seven hours, you're going to die early,” he told me. “That's not true.”

    Yet Americans are addicted to getting more sleep — and on turning to medical shortcuts to help them.

    According to the Centers for Disease Control, as many as 70 million U.S. adults suffer from sleep disorders or sleeplessness. Only a third of Americans get the government's recommended seven to nine hours of sleep a night.

    About 9 million American adults use sleeping pills to help get a good night's rest, the CDC found. Siegel said the number of people relying on medicines “has gone up rather rapidly since then.”

    Industry consulting firm Global Data estimates that worldwide sales for sleeplessness medicines will run about $1.4 billion next year and reach $1.8 billion by 2023, recovering from lower sales in recent years because of cheaper generics(仿制药) hitting the market.

    Dr. Roy Artal, a sleep specialist in West Los Angeles, said it's understandable that busy people in today's go-go world would turn to medicines to speed up the sleep process. But all they're doing is building a reliance on powerful drugs for relatively little improvement.

    “There's no magic pill that makes us sleep when we want and wake up when we want,” Artal said. “The effects of sleeping pills tend to be modest.”

    He and other experts say the answer to sleeplessness isn't to be found in a pill bottle. It's in what's called “sleep hygiene (保健).”

    A “lost tribe” that reached America from Australia may have been the first Native Americans, according to a new theory.

    If proved by DNA evidence, the theory will break long established beliefs about the southerly migration of people who entered America across the Bering Strait, found it empty and occupied it.

    On this theory rests the belief of Native Americans to have been the first true Americans. They would be classified to the ranks of escapee, beaten to the New World by Aboriginals (土著人) in boats.

    To a European, this may seem like an academic argument, but to Americans it is a philosophical question about identity, Silvia Gonzales, of Liverpool University said.

    Her claims are based on skeletons found in the California Peninsula of Mexico that have skulls quite unlike the broad Mongolian features of Native Americans. These narrow-skulled people have more in common with southern Asians, Aboriginal Australians and people of the South Pacific Region.

    The bones, stored at the National Museum of Anthropology (人类学) in Mexico City, have been carbon-dated and one is 12,700 years old, which places it several thousand years before the arrival of people from the North. “We think there were several migration waves into the Americas at different times by different human groups,” Dr. Gonzales said. “The timing, route and point of origin of the first colonization of the Americas remains a most contentious topic in human evolution.”

    But comparisons based on skull shape are not considered conclusive by anthropologists, so a team of Mexican and British scientists, backed by the Natural Environment Research Council, has also attempted to take out DNA from the bones. Dr. Gonzales declined yesterday to say exactly what the results were, as they need to be checked, but indicated that they were consistent (一致) with an Australian origin.

    Researchers are trying to figure out exactly when and where a lizard got trapped in the sap(汁、液) of a tree. Over time, the tree sap turned into amber (琥珀), preserving the lizard's mains, which a man discovered and donated to the Miller Museum of geology at Queen's University. But the man didn't report the amber's age and where he got it.

    “The man who donated it died, unfortunately,” said Ellen Handyside, an undergraduate student at Queen's University. “We are really starting from scratch in determining its history Ellen Handyside is leading the research into the amber-surrounded lizard. She and her colleagues analyzed the chemical composition of the 4.7-inch -long piece of amber and learned some facts. “The amber wasn't actually artificial,” she told Live Science, “and we found that it did match up quite well to an amber sample.”

    The researchers analyzed the amber's carbon and hydrogen isotopes(同位素) and the results indicated that the amber was formed from the sap of a flowering tree. Moreover, the results suggested that the tree and the lizard, for that matter, lived in an area with a lot of rainfall and dated to the Neogene, a period that lasted from the end of the Paleogene Period 23.03 million years ago to the beginning of the present Quatemary Period. Next, the scientific team realized that the 2.7-inch-long lizard was likely a gecko(壁虎), according to a detailed, 3D, digital model of the animal's body that the researchers created through X-ray microscopy scans.

“We looked at the skull —the teeth are in place and the ear bones are there too. And we've even got some flesh, skin and its long toes,” Handyside said. “It's fantastic!” She said she hoped that they could figure out how the creature fit into the gecko family tree. “When you think of a gecko, you think of short and fat toes and sticky pads. That isn't what we're looking at, but it's more likely to live in trees. If it were a tree-living creature, then its death actually could make more sense,” Handyside said.

    Would it surprise you to learn that, like animals, trees communicate with each other and pass on their wealth to the next generation?

    UBC Professor Simard explains how trees are much more complex than most of us ever imagined. Although Charles Darwin thought that trees are competing for survival of the fittest, Simard shows just how wrong he was. In fact, the opposite is true: trees survive through their co-operation and support, passing around necessary nutrition (营养) “depending on who needs it”.

    Nitrogen (氮) and carbon are shared through miles of underground fungi (真菌) networks, making sure that all trees in the forest ecological system give and receive just the right amount to keep them all healthy. This hidden system works in a very similar way to the networks of neurons (神经元) in our brains, and when one tree is destroyed, it affects all.

    Simard talks about “mother trees”, usually the largest and oldest plants on which all other trees depend. She explains how dying trees pass on the wealth to the next generation, transporting important minerals to young trees so they may continue to grow. When humans cut down “mother trees” with no awareness of these highly complex “tree societies” or the networks on which they feed, we are reducing the chances of survival for the whole forest.

    “We didn't take any notice of it.” Simard says sadly. “Dying trees move nutrition into the young trees before dying, but we never give them chance.” If we could put across the message to the forestry industry, we could make a huge difference towards our environmental protection efforts for the future.

    There are many programs for high school students today that help lonely teenagers deal with loneliness. However, loneliness is not only a problem for teens but also an important and rarely acknowledged one in the elderly.

    In Britain, Tracey Crouch was appointed to be the first Minister of Loneliness in order to address the problems caused by loneliness. This is the first time such a position has been created.

    In Britain, there are around 9 million people who say they are lonely frequently. In Germany, a study conducted by Ruhr University Bochum found that 20 percent of people over the age of 85 felt lonely, and 14 percent of those between age 45 and 65 felt socially lonely. In the United States, more than 25 percent of the population live alone, more than 50 percent are unmarried.

    Loneliness is generally associated with heart disease  overweight, and anxiety. Additionally, the stress from loneliness can cause your cells to change on a molecular (分子) level that reduces its abilities to defend your body against diseases. In fact, doctors believe having feelings of loneliness is equivalent to smoking 15 cigarettes per day in regard to its effect on health!

    In Britain, the new Minister of Loneliness will help introduce government policies on the problem and fund a charity—an organization for helping people in need, to devote their efforts towards aiding loneliness. There are charities that link lonely seniors to high school students in order to give them a line of communication whenever they feel lonely!

    The possibilities for the new Minister of Loneliness are endless. For example, she can provide education services to household businesses so that they can identify lonely customers if they see one. Loneliness fits into the category of being a social problem that must be monitored by the entire community in order to help those in need. Therefore, government involvement in medical services and care for seniors and others is vital for happy seniors.