It was 3:21 a.m. when nine-year-old Glenn Kreamer awoke to the smell of burning. Except for the cracking(爆烈声) of flames somewhere below there was not a sound in the two-storey house at Baldwin Long Island.

    With his father away on night duty at a local factory, Glenn was worried about the safety of his mother, his sister Karen, 14 and his 12-year-old brother Todd. He ran downstairs through the smoke-filled house to push and pull at Karen and Todd until they sat up. Then he helped each one through the house to the safety of the garden. There, his sister and brother, taking short and quick breaths and coughing, fell down onto the lawn.

    The nine-year-old boy raced back into the house and upstairs to his mother's room. He found it impossible to wake her up. Mrs. Kreamer, a victim of the smoke, was unconscious(昏厥的), and there was nobody to help Glenn carry her to the garden. But the boy remained calm and, as a fireman said later, "acted with all the self-control of a trained adult."

    On the bedroom telephone, luckily still working, Glenn called his father and, leaving Mr. Kreamer to telephone the fire brigade and ambulance service, got on with the task of saving his mother.

    First he filled a bucket with water from the bathroom and threw water over his mother and her bed. Then, with a wet cloth around his head he went back to the garden.

    He could hear the fire engine coming up, but how would the firemen find his mother in the smoke-filled house where flames had almost swallowed up the ground floor?

    Grasping firmly a ball of string(线) from the garage, Glenn raced back into the house and dashed upstairs to his mother's room. Tying one end of the string to her hand, he ran back, laying out the string as he went, through the hall and back out into the garden.

    Minutes later he was telling fire chief John Coughlan, "The string will lead you to mother." Mrs. Kreamer was carried to safety as the flames were breaking through her bedroom floor.

    To save as much language diversity as possible in the face of its rapidly dying out, researchers suggest using “evolutionary trees”, a tool from conservation biology.

    One of the world's 7,000 languages disappears every other week, and half might not survive the 21st century, experts say.

    When setting conservation goals, ecologists use evolutionary trees—diagrams that show how biological species are related to one another—to identify species that have few close relatives. Such species are said to be evolutionarily distinct. Similarly, recent advances in the construction of language trees make it possible to measure how unique a language is.

    “Evolutionary trees have transformed our understanding of how life has evolved and helped us to decide which species most need conserving,” says Jonathan Davies, senior author of the new study.

    “The rapid rate of language loss, as well as limited resources for preservation（保护）, means that we must choose carefully where to focus our efforts,” adds Max Farrell, a PhD student in Davies' lab. “The more isolated (孤立的) a language in its family tree, the more unique information it contains and eventually contributes to language diversity.”

    As a case study, they used this approach to rank 350 Austronesian languages, spoken in islands spread across Southeast Asia and the Pacific Ocean.

    For each of these languages, the researchers combined measures of evolutionary distinctiveness (ED) and global endangerment (GE) to produce an “EDGE” score. The language with the highest score, which means it is extremely distinct（不同的） yet nearly dying out, was Kavalan, a language native to Tai Wan. The next-highest scores went to Tanibili, an endangered language in the Solomon Islands.

    By building trees for other language groups, language specialists could target preservation efforts and help reduce the loss of language diversity in the future, the researchers say.

Dogs are man's best friends—they are very good for children's health. Researchers found that family pets helped to protect babies against breathing problems and infections (感染).

    A team from Kuopio University Hospital in Finland studied 397 babies born at their hospital between September 2012 and May 2015 for their first year. They found that babies who lived with a dog or a cat spent fewer weeks with ear infections, coughs or runny noses. They were also less likely to need antibiotics (抗生素) than babies in homes without a pet.

    Study author, Dr. Eija Bergroth, said dogs brought dirt and bacteria (细菌) into the home, which helped children's immune system (免疫系统) to be strong. This improved their defenses against bacteria.

    As part of the study, parents filled out weekly diaries starting when the children were nine weeks old, recording information on babies' health as well as their contact with cats and dogs. They recorded if they had fever, ear infections, coughs or running noses. They also put down whether they needed antibiotics.

    Based on those diaries, the researchers found that about a third of the children spent most of their first year with a pet dog and 24 percent in a home with a cat. And children with no dog contact at home were healthy for 65 percent of the time, compared to between 72 and 76 percent for those who did have a pet.

    The researchers also found that contact with dogs, more than cats, was tied to fewer weeks of sickness for babies.

    However, the researchers said they couldn't rule out the possibility that people who own dogs are less likely to get sick for another reason, not due to any protection offered by pets.

    Halloween is a holiday full of tricks and treats and all things frightening and fun. But what happens when you trade your sweets for a scare? The result is always healthier than candy.

    Being frightened can be good for you. Think about your favorite scary books or movies. You are scared but you just can't resist reading or watching them. Being frightened makes your brain flood with healthy chemical substances that excite your mood and release feelings of great excitement.

    When you're frightened, your body also produces a chemical called oxytocin, which helps people bond with one another. So, if you're at a haunted(闹鬼的) house with some pals, that experience can help strengthen your friendship. “Watch people walking out of a haunted house, and you'll see lots of smiles and high fives,” says Dr. Margee Kerr, a sociologist who studies fear.

    There is also some evidence that being scared can help a person manage stressful situations. Things like giving a presentation in front of your class or performing in a school play can make us fearful and anxious. But these experiences help build a sort of endurance to fear that makes us more confident. “You become more comfortable with the physical experience of fear, and so you're better able to work through it during tense situations,” Kerr explains.

    Though some haunting may be healthy, it's important to remember that people experience fear in different ways. What may be fun for one person could be too scary for another. And Kerr notes that kids younger than six and or seven can't separate real and make-believe, so seeing something frightening could have lasting, negative effects.

Babies made from three people approved in UK

    Babies made from two women and one man have been approved by the UK's fertility regulator. The historic and controversial move is to prevent children from being born with deadly genetic diseases.

    Doctors in Newcastle — who developed the advanced form of In Vitro Fertilization or IVF (人工授精) — are expected to be the first to offer the procedure and have already appealed for donor eggs. The first such child could be born, at the earliest, by the end of 2017.

    Some families have lost multiple children to incurable mitochondrial (线粒体的) diseases, which can leave people with insufficient energy to keep their heart beating.

    The diseases are passed down from only the mother, so a technique using a donor egg as well as the mother's egg and father's sperm has been developed.

    The resulting child has a tiny amount of their DNA from the donor, but the procedure is legal and reviews say it is ethical (伦理的) and scientifically ready.

    "It is a decision of historic importance," said Sally Cheshire, chairwoman of the Human Fertilisation and Embryology Authority (HFEA). "I'm sure patients will be really pleased by what we've decided today."

    But some scientists have questioned the ethics of the technique, saying it could open the door to genetically-modified(转基因) 'designer' babies.

    The HFEA must approve every clinic and every patient before the procedure can take place. Three-person babies have been allowed only in cases where the risk of a child developing mitochondrial disease is very high.

    Prof Mary Herbert, from the Newcastle Fertility Centre, said, "It is enormously pleasing that our many years of research in this area can finally be applied to help families affected by these devastating diseases".

    "Now that we are moving forward towards clinical treatments, we will also need donors to donate eggs for use in treatment to prevent affected women transmitting disease to their children."

    Prof Sir Doug Turnbull, the director of the Welcome Centre for Mitochondrial Research at Newcastle University, said, "We are delighted by today's decision. We will also provide long-term follow up of any children born."

    NHS England has agreed to fund the treatment costs of the first trial of three-person IVF for those women who meet the HFEA criteria, as long as they agree to long-term follow up of their children after they are born.