SCIENCE IN THE NEWS - Polio Vaccine Ban in Parts of Nigeria(在线收听) |
SCIENCE IN THE NEWS - Polio Vaccine Ban in Parts of Nigeria / Safety Laws Urged for India / Two More Elements? Broadcast: Tuesday, March 02, 2004 (THEME) VOICE ONE: This is SCIENCE IN THE NEWS, in VOA Special English. I'm Bob Doughty. VOICE TWO: And I'm Faith Lapidus. On our program this week: Some local leaders in Nigeria continue to resist the fight against polio ... VOICE ONE: Indian lawmakers call for stronger safety rules for food and drink. VOICE TWO: And, chemistry students may get two more elements to learn. (THEME) VOICE TWO: In Nigeria, Islamic leaders in several northern states have banned the vaccine that prevents polio. Leaders in Kano and the other states say the vaccine is unsafe. They say the medicine contains chemicals that give people AIDS or prevent females from having babies. They say it is part of an American plot. VOICE ONE: The World Health Organization and the Nigerian government have done tests. Health officials say the vaccine is completely safe. They also asked Islamic leaders to help test the vaccine. Recently the Nigerian government appointed a committee to gather the facts. Last week the chairman said the committee was still waiting for the results of a test performed in India. He said the committee does not expect to release its final report to the public until early March. VOICE TWO: The ten countries in the vaccination campaign last week included Benin, Burkina Faso, Central African Republic, Chad and Cameroon. The others were Ghana, Ivory Coast, Niger, Togo and Nigeria. Also last week, the W-H-O reported a case of polio in Ivory Coast. The agency said Ivory Coast could be the eighth polio-free country re-infected because of the spreading virus from northern Nigeria. The disease causes paralysis. Victims lose the use of their arms or legs. The "Kick Polio Out of Africa" campaign began in nineteen-ninety-six. The W-H-O says two-hundred-five children each day were becoming paralyzed. By last year, however, just three-hundred-eighty-eight cases of polio were reported in Africa. That was almost half of all the new cases of polio in the world. The international goal is to defeat polio by the end of this year. Health officials say that may be impossible if the bans on the vaccine continue in northern Nigeria. (MUSIC) VOICE ONE: Indian lawmakers have confirmed that Coca-Cola and Pepsi drinks made in India contain pesticides. These poisons are used to kill insects on farms and in homes, but they can enter water supplies. The investigation showed that the pesticides came from the groundwater used in the drinks. The lawmakers said the problem is that India's food safety rules do not prevent this kind of situation. The committee reported tests on twelve kinds of soda drinks made by the Coca-Cola and Pepsi companies. The report said the tests found high levels of four pesticides. The companies say the drinks they make in India are safe and follow internationally accepted methods of production. Coke and Pepsi products are reported to control about eighty percent of the Indian soda market. Coca-Cola says it had twenty-two percent growth in India last year. VOICE TWO: The lawmakers began to investigate after an Indian public interest group reported about the pesticides. The Center for Science and Environment carried out the first tests. Its researchers used three bottles of each of the twelve kinds of sodas. They bought the drinks from different stores around New Delhi. The group says its laboratory workers tested all the drinks for sixteen kinds of pesticides. The researchers said they found one pesticide, lindane, in all the drinks tested. Lindane can be highly dangerous to humans. VOICE ONE: The researchers say most of the tested drinks also contained DDT. This pesticide is banned in the United States and some other countries. It can affect the central nervous system and cause problems during pregnancy. The United States Environmental Protection Agency says DDT is also believed to cause cancer. However, DDT remains popular in India to kill mosquitoes. The researchers said PepsiCo and Coca-Cola need better technology to remove poisons from the groundwater they use. However, the parliamentary investigators noted that neither company violated any Indian laws. The lawmakers say it is the laws that have to change. (MUSIC) VOICE TWO: All matter in the world is made of elements. Oxygen, for example, is the most common element on Earth. Elements are substances that cannot be separated into simpler substances by chemical methods. However, scientists can use nuclear reactions or radioactive decay to produce new elements. The goal is to find new materials and new ways to do chemistry. Russian and American scientists recently announced the discovery of two new chemical elements. Their findings appear in the magazine Physical Review C. VOICE ONE: Each element has a different number of protons in its nucleus. Protons are particles with a positive electrical charge. How many protons an element has establishes its place on the periodic table. This is the list of all the elements. Hydrogen, for example, is element number one. It has only one proton. It is the lightest gas known. Uranium is the heaviest element in nature. It has ninety-two protons. Elements with more than ninety-two protons are called superheavy elements. The two new elements are to appear as numbers one-hundred-thirteen and one-hundred-fifteen on the periodic table. VOICE TWO: The Russian scientists are from the Joint Institute for Nuclear Research in Dubna. They worked with researchers at the Lawrence Livermore National Laboratory in California. The two teams shot electrically charged protons of calcium at a target. This target was enriched americium. Americium is a radioactive metal. Very small amounts are commonly used in smoke detector devices. The scientists reported that a series of reactions created four atoms found in element one-hundred-fifteen. They say the atoms existed for ninety milliseconds. A millisecond is one-thousandth of a second. Then the atoms decayed into the other new element, with one-hundred-thirteen protons. The scientists say it remained this way for more than a second. Then it changed into known elements. VOICE ONE: The length of time that a nucleus can exist is very important. It is a measure of stability. Atoms that are forced together usually break apart quickly if the combined nucleus has more than ninety-two protons. For years researchers have been looking for what they call an "island of stability" on the periodic table. They believe that a nucleus with about one-hundred-fourteen protons may be able to exist for a long time. The two new elements have been named ununtrium and ununpentium. These are temporary names. The scientists will be able to choose others. VOICE TWO: But first the International Union of Pure and Applied Chemistry must confirm their discovery. Two years ago, a scientist in the United States provided false evidence about the discovery of element one-hundred-eighteen. Other laboratories must be able to reproduce findings of new elements. There are also rules about names. An element can be named after a mythological idea, a mineral, a place or country, a property, or a scientist. (MUSIC) VOICE ONE: It appears that insects existed on Earth twenty-million years earlier than thought. In fact, a new finding suggests that insects were among the first creatures on land. Two scientists from the United States have reported the discovery of a four-hundred-million-year-old insect. It was found in Scotland almost eighty years ago. But there was little interest until the two scientists rediscovered the fossil in a London museum. Next week, we will have more details about their findings. (THEME) VOICE TWO: SCIENCE IN THE NEWS was written by Karen Leggett, Jill Moss and Caty Weaver. Our producer was Cynthia Kirk. This is Faith Lapidus. VOICE ONE: And this is Bob Doughty. Listen next week for more news about science, in Special English, on the Voice of America. |
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