Happy Birthday to the Mouse
This month is the 30th birthday of the mouse. No, we're not talking Mickey or Minnie. In 1968, the computer mouse made its first appearance at a computer show in San Francisco.
At the time, computers were large machines, used mainly for number crunching. Computer monitors were rare, and personal desktop computers were many years away. Douglas Engelbart, working at the Stanford Research Institute, wanted to make computers more user-friendly. He built his first monitor in 1964 - it cost $80,000. Later, he designed an easy way to navigate around the screen. It was a small wooden box sitting on top of two flywheels. One flywheel rolled back and forth, the other rolled sideways. (Today's mice use a ball instead of the flywheels.) It was patented as an "X-Y Position Indicator for a Display System" but was quickly nicknamed a "mouse." The name stuck, and so did the idea. Since 1968, hundreds of millions of mice have invaded homes and offices around the world. Happy 30th birthday to the computer mouse.
It sounds like science fiction - a brain implant which lets a person communicate directly with a computer. However, it is now a reality. Six months ago, doctors at Emory University put a small electronic device inside the brain of a paralyzed man, who was unable to move or talk. The device amplifies (increases the power of) his brain signals, and sends them to a laptop computer. The man has learned how to control a cursor on a computer screen to point at messages. He can now communicate hunger or thirst, and use phrases like "see you later." The doctors hope to add other functions soon, like writing letters and turning the lights on and off.
Growing New Brain Cells
Scientists have discovered that people can grow new brain cells. Doctors used to believe that no new brain cells, called neurons, grow after you are born. When brain cells died, they could never be replaced. This belief lasted a long time, even though it was not based on any scientific data. Over the past 30 years, scientists doing research on animals found that many adult birds and mammals grow new brain cells. For example, mice given a more interesting environment, including more toys and the company of other mice, grew new brain cells and did better on behavioral tests.
Last spring, scientists found that new cells grow in the developing brains of young children. Between birth and age six, about 400 billion new cells form. And now, scientists report that adult brain cells also grow and divide. They found the new cells in the "hippocampus," an area important for memory and learning. This discovery may one day lead to medical treatments that repair diseased or damaged brains.
Math for Monkeys
How smart are monkeys? Many scientists believe that animals can not think because they do not have language. But others are trying to find out whether animals can think without language. In a study at Columbia University, two rhesus monkeys have learned to do some simple math. The monkeys can put pictures of one to nine objects into numerical order.
That is different than counting from one to nine. People count using symbols, like 1, 2, 3, which stand for the idea of numbers. The scientists at Columbia want to find out whether monkeys can also learn to count from one to nine using symbols. The symbols will be textures instead of numbers. They will teach the monkeys to match each texture with a certain number of objects. Then they will test whether the monkeys can put those textures in numerical order, which would show they can count.
Leonid Meteor shower - Update
Now that it's over, how did this meteor storm compare to expectations? Some sky watchers were disappointed, especially in parts of Asia, while Southern Europe got a better show than expected. Some locations reported about 2,000 meteors per hour, but most people saw far fewer. There were more fireballs than expected. A few of them shone as brightly as the full moon. There was no reported damage to any satellites. If you did not get a chance to see the show, you may get another chance, same time next year. (See the original article in October's News.)
Hand Transplant - Update
Clint Hallam, the man who received a hand transplant on Sept. 23, is doing well. He has begun moving the fingers of the donor hand, and there have been no signs of rejection. (See the original article in October's News.)
Leonid Meteor shower - November 17-18
Every day, dozens of meteors enter the Earth's atmosphere. Most of them never reach the ground. Instead, they burn up as they streak through the sky. We often call them shooting stars or falling stars.
("Meteoroids" are objects moving through space towards the Earth. A meteoroid that enters the atmosphere is called a "meteor." If the object reaches the ground it is called a "meteorite.")
Occasionally, there are meteor showers or storms, where hundreds or even thousands of meteors can be seen. The Leonid meteor shower occurs every year in mid-November, this year on November 17 & 18. For some lucky viewers, it may be quite a show. The best place to see the meteors this year will be in East Asia. The shower is expected to peak at about 2:20 p.m. EST. This means that for people living in the United States, most of it will occur during daylight. But if you are willing to get up early in the morning, you may see more meteors than usual. Look for them in the eastern sky, from about 1 a.m. local time until dawn, on November 17 and 18. The best time should be about 3:00 a.m. The meteors will seem to come from the direction of the constellation Leo, which is why this is called the Leonid shower.
The Leonid meteors come from the Comet 55P/Tempel-Tuttle. This comet takes just over 33 years to orbit the Sun. As it approaches the Sun and warms up, bits of dust, gas and small particles break off, forming a tail. Over many centuries, these particles have spread out, forming a trail along the comet's orbit. The Leonid meteor shower occurs each year as Earth passes through this trail. When Earth passes through the comet's tail soon after the comet goes by, we have a major meteor storm.
The comet poses no direct danger to people on Earth. It has never come close to hitting the planet. Most of the meteoroids are smaller than grains of sand, and they burn up high in the atmosphere. But this storm could cause other serious problems. It is the first since 1966 and the early days of the space program. The potential effects on spacecraft are unknown. The fast-moving particles, travelling over 155,000 mph, could be a danger to orbiting satellites. Large particles could poke holes in the equipment, causing serious damage. Another danger is "sand-blasting" by smaller meteoroids. This can cause extra wear and tear, and do major damage to lenses, mirrors and other optical equipment. Electrical damage is also a possibility. When tiny, fast-moving particles hit a satellite, they are vaporized into a plasma. A plasma is a very hot, electrically-charged gas. It could cause short circuits and damage to computer chips and other electronics. During the Perseids meteor shower in 1993, electrical damage caused a European communications satellite to spin out of control.
Satellite operators are taking precautions. Many of the satellites will be moved or turned to reduce the exposed area and protect delicate instruments. The only people in space will be the crew of the Russian Mir space station. The cosmonauts will stay in the Soyuz reentry vehicle during the storm, so that if necessary, they can safely return to Earth.
Doctors in France have transplanted the hand and forearm from a dead donor to a man who lost his hand in an accident in 1984. They attached "all the arteries, veins, nerves, tendons, muscles and skin after setting the two bones of the forearm." A similar transplant was tried in 1964. It failed when the transplanted hand was rejected after two weeks. Doctors believe that improvements in surgery methods and anti-rejection drugs have increased the chances for success this time. So far, the man appears to be doing well, although it will be many months before doctors know whether the hand will work.
Rejection is a serious problem for all transplant patients. The human immune system fights bacteria, viruses, and other foreign materials that enter the body. Transplant recipients must take strong drugs for the rest of their lives to suppress this normal response. Otherwise, the immune system would attack the transplant, causing rejection. Unfortunately, the anti-rejection drugs can have serious side-effects, and make the recipient less able to fight off infection and disease.
Soon after the transplant operation, this story took a strange twist. Originally, the patient, Clint Hallam, was identified as an Australian businessman who lost his hand in a logging accident. Actually, Mr. Hallam lost his hand in an accident while in prison. The hand was reattached, but amputated 5 years later because it did not work. It turns out that the only man with two different sets of fingerprints has a long criminal record, and is currently facing additional trouble with the law.
The planet Saturn has bright, wide rings. You can easily see them with a good backyard telescope. It was not until 1979 that faint, thin rings were discovered around Jupiter. Later, rings were also found around Uranus and Neptune.
Scientists have known that Saturn's rings are made of ice. But the makeup of Jupiter's rings was not known. Now, after studying new pictures from the Galileo spacecraft, scientists think that Jupiter's rings are made of dust. The dust comes from the planet's four small inner moons. Jupiter's strong gravity pulls in asteroids and other bits of space debris, which hit the moons at high speed. The impacts throw out clouds of dust, and the dust forms rings. The new pictures clearly show dust coming off two of the moons, Amalthea and Thebe. A similar process may have made the rings around Uranus and Neptune.
Turn Off the Lights (and Other Gadgets, Too)
All those electrical gadgets around your house may be using more energy than you think.
Electrical appliances obviously consume power when they are being used. But many appliances are kept on for long periods of time, even when they are not in use. And although they use less power in "standby," the wasted energy adds up over time. A report in "New Scientist" magazine says that many household appliances consume more energy while idle than in actual use. This wasted energy costs U.S. consumers $1 billion a year. The report blames the wasted power on poorly designed appliances.
Is it just your imagination, or does it really rain more often on weekends?
Scientists studied 17 years of weather records for the Atlantic Ocean along the East Coast of North America. They found a definite weekly pattern. During that time, average rainfall was lowest on Mondays, then increased during the rest of the week. Saturdays had the most rain.
Why does this happen? Air pollution builds up during the work week. Cars are probably the main cause. Some of the pollutants are aerosols - tiny solid particles and drops of liquid suspended in the air. Scientists think the aerosols absorb the sun's heat. The air heats up and rises. More clouds form, bringing more rain.
The Disappearing Data
You may think that electronic and computerized information storage is permanent, but think again. Much of the digital information saved over the past several decades is either in danger of being lost or already gone.
There are two main problems. The first is that hardware and software are changing so fast. Old files and data may not be readable by the new systems. And even when old data is transferred to a new system, some of the information can be mixed-up or lost in the process.
The second is physical decay. Digital tapes and disks may last only 5 to 10 years. Even CD-ROMS may not last any longer than that. Experts have discovered that magnetic fields, humidity and oxidation can erase information stored on CDs.
The government and industry are looking at ways to fix this growing problem. Two companies have come up with solutions that may seem more like a step back in time. One company is converting digital information back to analog form for storage. The other is storing digital data on - believe it or not - paper.
Why Are Old Windows Thicker at the Bottom?
Glass windows in very old buildings and churches are often much thicker at the bottom than at the top. The usual explanation is that glass is not really a solid, but a "supercooled" liquid that slowly flows downward over time.
A new study shows that this idea is incorrect. Glass flows extremely slowly at normal temperatures. A Brazilian scientist, Edgar Dutra Zanotto, has calculated how long it takes different kinds of glass to flow. For the windows to be noticeably thicker at the bottom, it would take a period of time "well beyond the age of the universe," says Zanotto. His calculations prove what other scientists have said before. Old windows are not thicker at the bottom because the glass flows down.
So why are the bottoms thicker? Probably because of the way old glass windows were made. Molten glass was blown into a large hollow ball shape, which was then twirled and flattened. This made a round, rippled piece of glass which was thicker at the edges. The glass was cut, and the thicker sections were usually put at the bottom of the window. Today, most windows are made by floating molten glass on liquid tin. Glass made this way has a very even thickness and flat surface.
Bacteria Found in Unexpected Places
Bacteria and other microbes cause about 81 million cases of food poisoning in the United States each year. Raw and undercooked meat usually gets most of the blame. But some microbes on fruits and vegetables have also made people sick. Washing fruits and vegetables with water helps, but does not get rid of all the germs. Scientists are working on new germ-killing sprays and washes that will be safe enough to use on food. In one experiment, dipping fruit into a simple mixture of vinegar and hydrogen peroxide (available at pharmacies as a disinfectant) killed all the harmful bacteria. The new washes may be ready for sale soon.
Bacteria live in many unexpected places. Recently they were found in ponds where used nuclear fuel is stored (at Savannah River in South Carolina.) Radiation from the nuclear waste would be harmful to most life. Water in the ponds is kept very clean, so there is little food for the bacteria. But these, and other recently discovered kinds of bacteria, have adapted and learned to grow in difficult conditions.
Aluminum, a common metal, is harmful or toxic to most living things. So scientists were surprised to find bacteria that may actually need aluminum to grow. The bacteria live near geysers in Yellowstone National Park. Like many other bacteria found there, these are "thermophiles." (They live and grow at high temperatures.) These bacteria grow fastest at about 70 degrees Celsius (158 degrees Fahrenheit.) And the higher the temperature, the more aluminum they seem to need. Maybe someday these bacteria could be used to clean up soil contaminated with aluminum.
Too Much of a Good Thing?
If a little vitamin C is good for you, then more should be better, right? Maybe not. British scientists have found that too much vitamin C may actually harm you.
Many people take megadoses (very large doses) of vitamin C to prevent colds, and to protect themselves from harmful molecules called "free radicals." The free radicals attack other molecules in your body. They can damage your cells and DNA (genes) and may cause cancer, heart disease, cataracts and other problems. Some vitamins (including C) and other substances in food act as "antioxidants," which prevent the free radicals from doing harm.
Researchers gave 30 healthy people a daily supplement of 500 milligrams of vitamin C. (For adults, the recommended daily allowance is 60 milligrams.) As expected, the vitamin worked as an antioxidant for some parts of their DNA. But when the researchers looked at other parts, which had not been studied in earlier tests, the vitamin C had actually increased the amount of DNA oxidation. The vitamin had both good and harmful effects at the same time.
The researchers say that people should be cautious about taking too much vitamin C. As always, the best advice is to eat a healthy and varied diet, including lots of fruit and vegetables.
A New View of REM Sleep
Scientists still do not know why we sleep, or what causes sleep. We do know that during the night, you go from deep sleep to light sleep and back again several times. The light sleep is also called REM sleep. REM stands for rapid eye movement. It is during REM sleep that you dream. While dreaming, your eyes move rapidly back and forth. Most scientists believe that the eye movement is caused by the dreams.
Scientist Dr. David Maurice has a different idea. He says that you move your eyeballs while sleeping in order to get oxygen to the cornea. There are no blood vessels in your cornea. The cells absorb oxygen from the air and other parts of the eyeball. "The cornea is full of living cells and they need to be nourished," says Dr. Maurice. Maybe dreaming does not cause REM, but instead, it is the eye movements that cause dreaming.
Athletes and Concussions
Doctors say that athletes who get concussions often return to play too soon. If the first injury is not completely healed, another blow to the head, even a minor one, is very dangerous. It can cause rapid swelling of the brain and lead to death. In the United States, sports cause about 300,000 brain injuries a year (most of these are concussions), and about 500 deaths.
A concussion is a brain injury caused by a hit on the head. You can have a concussion without becoming unconscious. Symptoms of concussion include headache, nausea, blurred vision, confusion, memory loss, and problems with coordination and speech. Head injuries cause the loss of brain cells, and even though the brain seems to heal, repeated injuries in young people may cause problems later in life.
11-Year Old Scientist
Emily Rosa of Loveland, Colorado, had an interesting idea for her fourth grade science fair. The results of her experiment have been published in the Journal of the American Medical Association (JAMA). According to the Guiness Book of World Records, she may be the youngest person ever to have their work published in a major scientific journal.
"Therapeutic touch" has become a common alternative medical treatment. In therapeutic touch, healers move their hands above a patient's body, working on their "human energy field." It is taught at nursing schools and colleges, and used at many medical centers. Although many people believe the treatment works, others question whether it is effective.
Emily designed an experiment to test therapeutic touch. A screen was used to separate Emily and a healer. Emily flipped a coin to chose whether to put her hand near the healer's left or right hand. The healer then decided which hand Emily was near. She did 280 tests with 21 healers. They got the right answer only 44 percent of the time. If they had just guessed, they would have been right about half (50 percent) of the time.
The editors at JAMA said Emily's study was well done and the results were clear. Congratulations Emily, for making an important scientific contribution.
Farewell to Mars Pathfinder
The world watched as the Pathfinder spacecraft landed on Mars last summer. From July 4 to September 27, 1997, it sent home amazing pictures and daily weather reports. Then the signals stopped. NASA continued trying for months to regain communications, but finally gave up on March 11.
The mission was successful well beyond everyone's expectations. The lander was designed to last for a month, and the rover, named Sojourner, for just a week. Instead, they operated for almost 3 months. The lander sent back over 16,000 pictures. Sojourner travelled about 300 feet across the Martian surface, collecting data and over 500 pictures.
Ice on the Moon
The Lunar Prospector was launched on January 7 to orbit and study the Moon. Measurements made by the spacecraft's instruments have found water at both lunar poles. The water is in the form of small ice particles, mixed in with the Moon's soil. It has been found only at the poles in the shade of deep craters, where the temperature is 280 degrees Fahrenheit below zero. There may be 11 million to 330 million tons of ice (2.6 billion to 26 billion gallons of water) on the Moon. Scientists believe the Moon was hot and dry when it formed, and that the water came from comets.
The Prospector should continue to orbit and collect information about the Moon for at least a year.
About 10 million people in the U.S. have reading problems caused by dyslexia. Most people think of dyslexia as mixing up letters or reading words backwards. Instead, dyslexics are not able to break written words down into separate language sounds, called phonemes. (American English has 44 different phonemes.)
Scientists made maps of working brains using high-tech MRI equipment. These scans showed that dyslexics have less activity than normal in some areas of the brain, and more activity in other areas. This information may help doctors diagnose dyslexia sooner in children, and may lead to new and better treatments for the problem.
Simple life forms have been found living in some very extreme conditions here on Earth. Microbes and tiny worms live in the frozen deserts of Antarctica. Bacteria live in hot sulfur springs and undersea hydrothermal vents, at temperatures that would "cook" ordinary plants and animals. They survive by making special heat-resistant enzymes. (Enzymes are molecules needed to carry out the chemical reactions of life, including digestion, growth, reproduction, etc.)
Until now, only single cell plants and bacteria have been known to live at these very high temperatures. For more complex animals, the record holder was an ant living in the Sahara Desert, where the air temperature reaches 55°C (131°F.)
Now scientists have found tube worms 10 cm (4 inches) long that survive under amazing conditions. Named Pompeii worms, they cling to hydrothermal vents deep on the ocean floor, off the coast of Costa Rica. The tails of the worms are in water up to 81°C (178°F) while the water around their heads is much cooler, about 22°C (72°F.) In addition, they sometimes leave their tube to search for food in nearby 10°C (50°F) water. It is not known how they survive such a wide temperature range.
The water inside the worms' tubes contains sulfides and heavy metals which would be toxic to most other life. Scientists think that bacteria living on and around the worms may detoxify the environment. If so, these bacteria may one day be useful for cleaning up toxic waste sites.
Sunscreens --- Frequent sunburns early in life have been linked to later skin cancer. Since sunscreens are good at protecting against sunburn, most scientists believe that using sunscreen will help prevent skin cancer. But the rate of skin cancer has been rising for the last 25 years. This fact, and other new research, has made a few scientists question whether sunscreen protects against cancer or not. Until there is proof, most scientists and dermatologists continue to recommend the use of sunscreen, in addition to reducing time spent in the sun and covering up with protective clothes.
Food Poisoning --- Scientists are testing a new vaccine against E. coli, the dangerous bacteria that can cause food poisoning. One strain, known as E. coli 0157, causes about 20,000 cases of food poisoning in the U.S. each year, killing up to 250 people. If successful, the vaccine could protect humans against this disease. It could also be used on cattle, which are the most common source of the infection.
Chocolate --- Many people believe chocolate causes migraine and other headaches. Now, just in time for Valentine's Day, a new study shows that chocolate, by itself, is probably not to blame for those headaches, even in people who suffer frequent migraines.
The End of the Universe
How will the universe end? Will it continue to expand forever? Or will the force of gravity eventually cause it to collapse in on itself?
Studies over the last few years have hinted that there is not enough matter in the universe to stop the expansion. New observations of distant supernovas (exploding stars) support that idea. Two independent groups of scientists have studied over 40 of the brightest supernovas. They found that the oldest ones were receding (moving away) at the same speed as the younger ones. This means that the universe has been expanding at a constant rate, and should continue to expand at the same rate. The data also suggest that the universe is about 15 billion years old, much older than many astronomers had previously thought.
Warmest Year on Record
1997 was the warmest year on Earth, according to US government scientists, with an average surface temperature of just over 62 degrees Fahrenheit. This is 3/4 °F above normal, and was 0.15 °F above the previous record set in 1990. Since the start of this century, the Earth's average temperature has increased by about 1 °F. And the 1980's and 1990's have been the warmest decades since people began keeping records in the mid-1800's.
Most scientists believe that human activity is at least partly responsible for the rise in temperature. Burning oil and coal releases gases like carbon dioxide (CO2) which trap heat in the atmosphere. Last December, representatives from 150 countries met in Kyoto, Japan and agreed to reduce emissions of CO2 and 5 other "greenhouse gasses. "