WeChat is a social mobile application with voice and text messaging timeline and several social features like ‘Message in a Bottle'. WeChat, a popular instant messaging tool run by Tencent Holdings, aims to help users access mobile services without downloading separate apps, which experts said may challenge the business of smartphone app distributors such Apple Store.

This new feature, named ‘Mini Programs', allows WeChat users to find a variety of services such as ticket buying by scanning a QR (quick-response) code, saving them the trouble of installing a number of different apps on smart devices, according to the transcript of a speech by Zhang Xiaolong, Tencent's senior executive vice president, on Wednesday. The new function is expected to come online on January 9.

    Zhang, known as the father of WeChat, emphasized that ‘Min Programs' is not a mobile app distributing function.

    Still, experts and app developers said that the rollout (推出) of ‘Mini Programs' on WeChat will erode the market share of app distributors like Apple Store in China.

     “‘Mini Programs' will attract lots of start-ups, because a program based on WeChat can help them build up businesses at much lower costs,” a Shanghai-based app developer, told the Global Times Wednesday.

    If a start-up wants to promote its business via a separate application, it has to hire a special team to develop two different apps— one each for iOS and Android.

    Lsiunched in 2011, WeChat has evolved to include services such as ‘Order Taxi', ‘Food Delivery', e-commerce and payments from just an instant messaging app.

    Mexico sites on an island plateau (高原) surrounded by volcanic peaks, which makes air quality a constant concern for people who live there.

    In April, the country took a decisive step toward improving air quality by enacting a temporary ban on private and Federal vehicles in the city. The rule forbids people from driving in the city one day each week and one Saturday each month. Electric vehicles, government service vehicles, public transport options and school buses are not included in the ban.

    Mexico City isn't the first urban center to be involved in car-free living. But the ban is more than an awareness-raiser. It was enacted with the direct aim of solving air pollution. In March, the city sank into a deep brown haze of smog when the pollution levels passed the 200 mark. The city ordered some 1.1m of the area's 4.7m cars off the streets and also offered free bus and subway rides.

    Mexico City's temporary vehicle ban raises questions about the best ways to improve urban air quality. India, whose citizens breathe some of the world's dirtiest air, has tried a variety of solutions. Earlier this year, the Indian government started a 4% sales tax on new-car purchases.

    Beijing also has experience with cleaning the air. The city introduced alternate-day rules in advance of the 2008 Olympic Games, which produced good results. And then there is the London congestion (拥挤) charge, introduced in 2003. The charge has had a measurable effect on air quality.

For now, Mexico City — named by the United Nations as the most polluted city on the planet in 1992 — can look forward to the start of the region's rainy season, when daily showers will help lo clean the air.

    The meaning of silence varies among cultural groups. Silences may be thoughtful, or they may be empty when a person has nothing to say. A silence in a conversation may also show stubbornness, uneasiness, or worry. Silence may be viewed by some cultural groups as extremely uncomfortable; therefore attempts may be made to fill every gap (间隙) with conversation. Persons in other cultural groups value silence and view it as necessary for understanding a person's needs.

    Many Native Americans value silence and feel it is a basic part of communicating among people, just as some traditional Chinese and Thai persons do. Therefore, when a person from one of these cultures is speaking and suddenly stops, what maybe implied (暗示) is that the person wants the listener to consider what has been said before continuing. In these cultures, silence is a call for reflection.

    Other cultures may use silence in other ways, particularly when dealing with conflicts (冲突) among people or in relationships of people with different amounts of power. For example, Russian, French, and Spanish persons may use silence to show agreement between parties about the topic under discussion. However, Mexicans may use silence when instructions arc given by a person in authority rather than be rude to that person by arguing with him or her. In still another use, persons in Asian cultures may view silence as a sign of respect, particularly to an elder or a person in authority.

    Nurses and other care-givers need to be aware of the possible meanings of silence when they come across the personal anxiety their patients may be experiencing. Nurses should recognize their own personal and cultural construction of silence so that a patient's silence is not interrupted too early or allowed to go on unnecessarily. A nurse who understands the healing (治愈) value of silence can use this understanding to help in the care of patients from their own and from other cultures.

    As most people know, in the last few years, sandstorms have swept across many cities and areas of North China, polluting the air and disturbing daily lives of human beings. People look dirty and suffer many kinds of illnesses, such as breath difficulty. The sandstorm is such a serious problem that it has not only weakened the industrial and agricultural development of our country but also caused a lot of trouble to the living conditions of the Chinese people.

    Therefore, effective measures should be taken as soon as possible to stop its happening. So how should we deal with the frightening sandstorms?

    Some experts offer practical advice as follows: For one thing, more money ought to be put into tree planting and forest protection in order to keep more water on the Earth. For another, government of all countries should make laws on environment protection. For example, banning the use of throw-away chopsticks and punishing illegal tree cutting. Scientists should also study and find ways to lower the grade of its destruction and to improve the environment. As for some schools, education about sandstorms should be spread properly and timely to make more and more people attach great importance to this problem.

    How people look forward to sunny days with soft wind touching their faces now and forever! The golden days can come back so long as we try our best to protect the natural environment from today on. And the fact is that what I expect is not just a dream. There are some sweet fruits from the early efforts.

    Government in Tibet have denied the permanent( 永久的) closure of Mount Qomolangma National Nature Reserve.

    The announcement came after a report went viral online claiming the base camp of the world's highest mountain was "permanently closed due to heavy pollution" and caused a universal misunderstanding.

    Mount Qomolangma National Nature Reserve was set up in 1988. Covering an area of more than 33, 800 square km, it is home to one of the world's most weak ecosystems(生态系统).

    Kelsang, deputy director of the reserves administration, said ordinary tourists are allowed to visit areas around Rongpo Monastery, almost 5,000 meters above sea level. As for travelers who have a climbing permit, they can go to the base camp at an altitude of 5,200 meters. The mountaineering activities have been permitted by the regional forestry department.

    To conserve the environment surrounding Mount Qomolangma, China carried out three major clean-ups at an altitude of 5, 200 meters and above last spring, collecting eight tonnes of household wastes, human wastes and mountaineering trash. This year, the clean-up will continue, and the remains of mountaineering victims(受害者) above 8,000 meters will be centrally dealt  with for the first  time. Meanwhile, the number of people who stay at the base camp will be kept under 300.

Recently, there are 85 wildlife protectors in the reserve, and 1,000 herders have part-time jobs going around and cleaning up garbage.

These measures aim to strike a balance between various demands such as environmental protection, local poverty relief, mountaineering and education, said Wang Shen, county chief of Dingri at the mountain foot.

Learning, Fast and Deep

    Over the past five years researchers in artificial intelligence have become the rock stars of the technology world. A branch of AI known as deep learning, which uses neural(神经的) networks to scan through large volumes of data looking for patterns, has proven so useful that skilled practitioners can command high six-figure salaries to build software for Amazon, Apple, Facebook and Google.

    The standard route into these jobs has been a PhD in computer science from one of America's top universities. Earning one takes years and requires a personality suited to academia, which is rare among more normal folk.

    That is changing.

    Last month fast.ai, a non-profit education organization based in San Francisco, kicked off the third year of its course in deep learning. Since its foundation it has attracted more than 100, 000 students around the globe from India to Nigeria. The course and others like it, come with a simple idea: there is no need to spend years obtaining a PhD in order to practise deep learning. Creating software that learns can be taught as a craft, not as a high intellectual pursuit to be undertaken only in an ivory tower. Fast. ai's course can be completed in just seven weeks.

    To make it accessible to anyone who wants to learn how to build AI software is the aim of Jeremy Howard, who founded fast.ai with Rachel Thomas, a mathematician. He says school mathematics is sufficient. "No. Greek. Letters," Mr. Howard intones, pounding the table with his fist for punctuation.

    Some experts worry that this will serve only to create a flood of unreliable AI systems which will be useless at best and dangerous at worst. In the earliest days of the Internet, only a select few nerds, namely computer holies with specific skills, could build applications. Not many people used them. Then the invention of the World Wide Web led to an explosion of web pages, both good and bad. But it was only by opening up to all that the Internet gave birth to online shopping, instant global communications and search. If Mr. Howard and others have their way, making the development of AI software easier will bring forth a new crop of fruit of a different kind.