Visiting Joshua Tree National Park, California

    Joshua Tree National Park is nearly 800,000 acres (英亩) large and surrounds parts of the Mojave and Colorado Deserts in South-central California. Although deserted at first sight, the park is full of wildlife and provides a variety of entertainment activities from hiking to climbing. Within a three-hour drive, Joshua Tree National Park takes at least a full day to visit.

Things to do

    Hiking opportunities within the park include several choices, from 12 self-guided nature routines to all-day back-country hikes.

    Joshua Tree NP has nine camping grounds, and back-country camping is also allowed.

    Rock climbing is a popular activity in the park, which has 10 mountains greater than 5, 000 feet in height.

When to visit

    Joshua Tree NP is open 365 days a year, although the best time to visit is October through April, when temperature is milder. The peak season is when the wild flowers bloom, and the summer months are the least crowded.

What to bring

    In addition to your camera and telescope, be sure to carry lots of water. Park and guiding maps can be picked up at any of the three visitor centers.

Fees

    Parking fees: You can buy a seven-day vehicle permit (周票) for $ 15, a single entry permit for $ 5, or Joshua Tree National Park annual (每年的) pass for $ 60.

    Camping fees: They vary by camping ground

    There is an old style out there of young girls talking endlessly on the phone with one another. It's an idea that is far from untrue in many families. I remember being a twelve-year-old and spending some quality time on the phone with my girl-friends, even though we'd seen each other at school. I didn't really have anything to talk about, I guess, but I think I was just happy to have someone else to talk to and that someone wanted to talk to me.

    We call this phenomenon (现象) of girls going on forever over the regular phone “girl talk”. And these days, girl talk has spread far beyond the old phone-teens communicate with each other pretty much nonstop through cell phone, texting，online chat. Is girl talk a good thing? According to experts, it can be-in limited quantities.

    Girl talk has its place. But too much of it, especially the kind during which problems are talked about endlessly can be not such a good thing. Psychologists (心理学家) think that too much of that kind of talking can lead to emotional problems such as depression (沮丧) and anxiety. Girls, much more so than boys, will always think of a problem and get worried, making the problem worse other than solving it. The best way is to try to guide the conversation toward something positive, or to do something about the problem rather than sit around and chat about it endlessly.

    Running is often tiring and a lot of hard work, but nothing beats the feeling you get after finishing a long workout around the track.

    But while it's long been believed that endorphins (脑内啡）—chemicals in the body that cause happiness — are behind the so-called “runner's high”，a study suggested that there may be more to this phenomenon than we previously knew.

    According to a recent study published by a group of scientists from several German universities, a group of chemicals called endocannabinoids (内源性大麻素）may actually be responsible for this familiar great feeling.

    To test this theory, the scientists turned to mice.

    Both mice and humans release high levels of endorphins and endocannabinoids after exercise, along with many other chemicals. After exercising on running wheels, the mice seemed happy and relaxed and displayed no signs of anxiety.

    But after being given a drug to block their endorphins the change. However, when their endocannabinoids were block with a different drug, their runner's high symptoms seemed to fade.

    “The long-held notion of endorphins being responsible for the runner's high is false. Endorphins are effective pain relievers, but only when it comes to the pain in your body and muscles you feel after working out,”Patrick Lucas Austin wrote on science blog Lifchacker.

    Similar studies are yet to be carried out on humans, but it's already well known that exercise is a highly effective way to get rid of stress or anxiety.

    The UK's National Health Service even prescribes (开药方)exercise to patients who are suffering from depression.

    “Being depressed can leave you feeling low in energy, which might put you off being more active. Regular exercise can boost your mood if you have depression, and it's especially useful for people with mild to moderate (中等的）depression,” it wrote on its website.

    It seems like nothing can beat that feeling we get after a good workout, even if we don t fully understand where it comes from. At least if we're feeling down, we know that all we have to do is put on our running shoes.

    Microsoft has developed a new smartphone app that interprets eye signals and translates them into letters, allowing people with motor neurone disease to communicate with others from a phone.

    The GazeSpeak app combines a smartphone's camera with artificial intelligence to recognize eye movements in real time and convert them into letters, words and sentences. For people suffering from ALS（渐冻症）, also known as motor neurone disease, eye movement can be the only way they are able to communicate.

    "Current eye-tracking input systems for people with ALS or other motor impairments are expensive, not robust under sunlight, and require frequent re-calibration and substantial, relatively immobile setups," said Xiaoyi Zhang, a researcher at Microsoft who developed the technology.

    "To mitigate the drawbacks…we created GazeSpeak, an eye-gesture communication system that runs on a smartphone, and is designed to be low-cost, robust, portable and easy to learn."

    The app is used by the listener by pointing their smartphone at the speaker. A chart that can be stuck to the back of the smartphone is then used by the speaker to determine which eye movements to make in order to communicate.

    The sticker shows four grids of letters, which each correspond to a different eye movement. By looking up, down, left or right, the speaker selects which grids the letters they want belong to. The artificial intelligence algorithm is then able to predict the word or sentence they are trying to say.

    Zhang's research, Smartphone-Based Gaze Gesture Communication for People with Motor Disabilities, is set to be presented at the Conference on Human Factors in Computing Systems in May.

The Truth About the Environment

    For many environmentalists, the world seems to be getting worse. They have developed a hit-list of our main fears: that natural resources are running out, that the population is ever growing, leaving less and less to eat, that species are becoming disappeared in huge numbers, and that the planet's air and water are becoming ever more polluted.

    But a quick look at the facts shows a different picture. First, energy and other natural resources have become more abundant, not less so. Second, more food is now produced per head of the world's population than at any time in history. Fewer people are starving. Third, although species are indeed becoming disappeared, only about 0.7% of them are dying out in the next 50 years, not 25-50%, as has so often been predicted. And finally, most forms of environmental pollution either appear to have been best cured not by limiting economic growth, but by accelerating it.

    Yet public opinion surveys suggest that many people hold the belief that environmental standards are declining and four factors seem to cause this gap between what they know and what the reality is.

    One is the unbalanced budget for scientific research. Scientific funding goes mainly to areas with many problems. That may be wise policy, but it will also create an impression that many more potential problems exist than is the case.

    Secondly, environmental groups need to be noticed by the mass media. They also need to keep the money rolling in. Understandably, perhaps, they sometimes overstate their arguments. In 1997, for example, the World Wide Fund for Nature issued a press release entitled: „Two thirds of the world's forests lost forever'. The truth turns out to be nearer 20%.

    A third source of confusion is the attitude of the media. People are extremely more curious about bad news than good. Newspapers and broadcasters are there to provide what the public wants: That, however, can lead to significant misunderstanding. An example was that America came across EI Nino(厄尔尼诺) in 1997 and 1998. This climatic phenomenon was accused of breaking tourism, causing allergies, melting the ski-slopes, and causing 22 deaths. However, according to an article in the Bulletin of the American Meteorological Society, the damage was estimated at $4 billion but the benefits amounted to some $19 billion.

    The fourth factor is poor individual knowledge. People worry that the endless rise in the amount of things everyone throws away will cause the world to run out of places to dispose of waste. Yet, even if America's trash output continues to rise as it has done in the past, and even if the American population doubles by 2100, all the rubbish America produces through the entire 21st century will still take up only one 12,000th of the area of the entire United States.

    It is extremely important that we look at the facts if we want to make the best possible decisions for the future. It may be costly to be overly optimistic, but more costly still to be too pessimistic.

    Moscow city authorities have begun using comics (漫画) with characters from Russian fairy tales to explain to migrants (移民) how they should behave. They say a 100-page guide is needed to "keep a positive image" of the city and could help reduce "tensions" between natives and migrants. But critics have pointed out that foreign migrants and natives may be regarded as antagonists in the manual (手册).

    Russians and migrants have repeatedly flooded in Moscow recently. Many migrants from ex-Soviet republics in Central Asia, the Caucasus (高加索) and North Caucasus, arrive in Moscow every year, attracted by the capital's job opportunities and relatively high salaries. A significant number of them work in the Russian capital illegally.

    The new guide in Russian seeks to explain the "dos" and "don'ts" to migrants. They are urged not to cause trouble, by staring at women, or eating or talking loudly on the streets. They are also warned that the police may routinely (例行公事) stop them to check their documents.

    In the manual, Russia's famous "three warriors" are meant to represent the city's law enforcement agencies (执法机关), while Prince Yuri Dolgoruky (a historical character) is used for tours around Moscow. Meanwhile, Vasilisa the Wise and The Snow Maiden test the reader on Russia's language and history. A special section of the book explains the importance of following Moscow's strict residency and employment rules, stressing that migrants could otherwise be deported (驱逐出境) or banned from entry.

    The manual was written primarily for illegal migrants, Alexander Kalinin, who heads the group Support for Working Migrants in Moscow, told BBC Russian.

    "We want to raise their level of law awareness," he added.

    Migrant characters had initially (最初) been identified as representatives of different nationalities, but the book's authors later decided to drop this idea so as "not to offend anyone", said Mr. Kalinin.

    "The old conflict between Russian heroes and non-Slavic invaders is being revived," Yevgeny Varshaver, a migration expert told BBC Russian. He also suggested that the language used in the book would be "difficult" to understand for some migrants who were not native Russian speakers.