Why do human beings still risk their lives under ground and doing one of the dirtiest and most dangerous jobs in the world? It is an increasingly urgent question, given the recent mining accidents in Sago, W. Va and Huntington, Utah. A small group of engineers and robotics experts look forward to a day in the not-too-distant future when robots and other technology do most of the dangerous mining work.

    Robotic technology, in particular, holds much promise, McAteer says, especially when it comes to mapping mines and rescuing trapped miners — the special operations of the mining industry.

    One of the first mining robots was developed five years ago at Carnegie Mellon University's Robotics Institute. It was called Groundhog. It used lasers(激光器) to “see” in dark tunnels and map abandoned mines—some of the most dangerous work in the business.

    The latest design is called Cave Crawler. It's a bit smaller than Groundhog, and even more advanced. It can take photos and videos and has more sensors that can detect the presence of dangerous gases. Incredibly, the robot has a real sense of logic. If it comes across an obstacle it gets momentarily confused. It has to think about what to do and where to go next. Sometimes it throws a fit just like a real person.

    The greatest problem, though, is cost. The money of the earliest research project was provided by the government, but that money had dried up, and it's not clear where future money will come from. Partly for that reason, and partly because of advances in safety, mining is not nearly as dangerous as it was in the past. Since 1990, fatalities(致命性) have declined by 67% and injuries by 51% , according to the National Mining Association.

    Some experts predict that robots in mines will serve much of the same function that they do in the automotive industry. The robots do the most boring and dangerous jobs，but won't get rid of the need for human workers.

    Everyone takes drugs. Sometimes a drug might be called a herb but the effect is the same. Drugs and herbs can make life better for they are used to improve health. From the simplest headache to a cure for cancer, people believe that certain drugs can help them. But there is danger if the drugs are not used in a proper way.

    American teenagers sometimes use certain drugs to feel good. They call this “getting high”. The problem is that once a young man or a young woman has the feeling of “getting high”, they want to do it often. If school is boring or too hard, students might get depressed and a drug or herb might help them feel better. If the student takes too much of a drug, the body may change in a wrong way such as a confused mind, poor sight, a headache, and an uncomfortable stomach.

    Schools now have D．A．R．E．program which means Drug Abuse Resistance Education. This program was started so that young students from age 10 to 18 might understand how a drug affects their bodies. The main point of the program is education. Once a student understands certain drugs can cause ill health，he will know he should not use them.

    Education is the key to good nutrition as well. If a student eats correctly, he or she will be full of energy which leads to good study habits and good grades. Poor nutrition may cause the need for more sleep and poor concentration. Proper food is similar to the proper use of drugs. Both allow a healthy body to grow while misuse of them prevents a person from developing normally.

    As free as they make us, mobile phones still need to stay close to a power source. Soon that may change with "green" power.

    Three Chilean students got the idea for a plant-powered device(装置) to charge（使……充电） their cellphones, while sitting in their school's outdoor courtyard during a break from exams, with dead mobile phones. Then, one of them had an "aha" moment.

    “It occurred to Camila to say about plants,” said inventor Evelyn Aravena. “'Why don't you have a socket, if there are so many plants? 'After that, we thought, 'why don't they have a charging outlet（插座）? Because there are so many plants and living things that have the potential to produce energy, why not?'”

    Their invention—a small biological circuit called E-Kaia—uses the energy plants to produce during photosynthesis(光合作用). A plant uses only a small part of that energy and the rest goes into the soil, and that's where the E-Kaia collects it. The device plugs into the ground and then into your phone.

    "It's the most amazing project I've ever seen in my life, plain and simple. They brought this original model, and it worked — and that's when it all changed, at least from my personal point of view and I began to support them." said Mauricio Cifuentes.

    The device solved two problems for the engineering students — they needed an idea for a class project, and an outlet to plug in their phones.

    "Looking for a place to charge the notebook, which had no power, and the mobile phones, we weren't able to find anything because all the other students were in the same state of madness trying to find a place to charge their devices," said Aravena.

    But plants are everywhere, and the bio－circuit makes good use of their excess(过多的) power.

    The E-Kaia doesn't carry much charge but it's powerful enough to completely recharge a mobile phone in less than two hours.

    The student inventors have applied for patents（专利） on their technology, and expect the E-Kaia to go on sale in the near 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.

Pacific Science Center Guide

◆Visit Pacific Science Centerˈs Store

Donˈt forget to stop by Pacific Science Centerˈs Store while you are here to pick up a wonderful science activity or souvenir to remember your visit. The store is located upstairs in Building 3 right next to the Laser Dome.

    ◆Hungry

Our exhibits will feed your mind but what about your body? Our café offers a complete menu of lunch and snack options, in addition to seasonal specials. The café is located upstairs in Building 1 and is open daily until one hour before Pacific Science Center closes.

    ◆Rental Information

    Lockers are available to store any belongings during your visit. The lockers are located in Building 1 near the Information Desk and in Building 3. Pushchairs and wheelchairs are available to rent at the Information Desk and Denny Way entrance. ID required.

◆Support Pacific Science Center

Since 1962, Pacific Science Center has been inspiring a passion for discovery and lifelong learning in science, math and technology. Today, Pacific Science Center serves more than 1.3million people a year and brings inquiry-based science education to classrooms and community events all over Washington State. Itˈs an amazing accomplishment and one we cannot achieve without generous support from individuals, corporations, and other social organizations. Visit pacific science center.org to find various ways you can support Pacific Science Center.

New research into a long-lived tree has shown some of the tricks that have helped it survive for thousands of years. The ginkgo(银杏树) is a huge, slow-growing tree with fan-shaped leaves, native to China, but planted in parks and gardens across the world. Some of the largest ginkgoes are said to be more than 3, 000 years old.

In order to discover how these and other trees can live for so long, scientists from the US and China studied 34 healthy ginkgoes of different ages. The team studied growth rings in each tree's trunk(树干), as well as cells(细胞) from the bark, leaves and seeds. They found that 600-year-old trees were just as healthy as 2-year-olds.

To learn more, the team then looked in detail at the DNA of nine trees aged between three and 667 years old. DNA is the chemical in the cells of plants and animals that holds instructions that tell any living thing how to grow and develop-including what to do at different times in its life At the beginning of a tree's life, DNA instructs the cells in a seedling to divide quickly so the tree grows rapidly. The cells also make special chemicals to help the young plant survive difficult situations, such as disease. As most trees grow older, their DNA tells their cells to divide more slowly (so growth slows down) and to make fewer chemical defenses(防御).

Ginkgoes, however, do things differently. The team found that although their growth finally slows, both young and old trees make protective chemicals." The secret is keeping a really healthy defense system," said researcher Richard Dixon." As ginkgoes age, they show no sign of weakening their ability to defend themselves from things like disease. "Other trees that live for a long time may have the same ability.

For all their defenses, though, ginkgoes cannot live forever--they finally meet with deadly accidents such as fire, disease and storms. While they last, however, these leafy trees are some of the most beautiful trees in the world.