This is SCIENCE IN THE NEWS, in VOA Special English. I'm Doug Johnson.
And I'm Mario Ritter. Today, we will tell about the 2009 Nobel Prizes for discoveries in science. We also will tell about progress against acquired immune deficiency syndrome, better known as AIDS.
The Nobel Prizes for Chemistry, Physics and Physiology or Medicine are to be presented in Sweden this week. The winners were chosen by the Royal Swedish Academy of Sciences. They will receive their prizes at ceremonies in Stockholm on December 10th. The winners in each area of science will share a prize valued at 1,400,000 dollars.
Nobel week is a busy time in the Swedish capital. The winners m ake speeches, meet with reporters and attend parties. But the most important event is when the King of Sweden presents the honorees with their awards.
Among those expected to accept their prizes are Elizabeth Blackburn, Carol Greider and Jack Szostak. They share the Nobel Prize for Physiology or Medicine. This year, it is presented for solving a problem in biology.
The three honorees are working in the United States. Elizabeth Blackburn does her research at the University of California in San Francisco. Carol Greider works at the Johns Hopkins University School of Medicine in Maryland. Jack Szostak works from the Harvard University Medical School, the Massachusetts General Hospital and the Howard Hughes Medical Institute.
The Royal Swedish Academy of Sciences says it is honoring the researchers for showing how telomeres and the enzyme that makes them protect chromosomes.
A telomere is a structure of genetic material. Telomerase is the enzyme in the body that builds the telomeres. A chromosome contains molecules of deoxyribonucleic acid, better known as DNA. This material carries the genetic information that makes us who we are. A telomere is at each end of a chromosome. Telomeres are necessary for a cell to divide.
The identification of telomeres about 20 years ago helped scientists understand how cells operate. But it was a finding that did not at first seem important to everyday life. Scientists now know that telomeres are involved in two subjects of widespread interest – aging and cancer.
The winners of the Nobel Prize in Physiology or Medicine were involved in the findings. Elizabeth Blackburn and Jack Szostak discovered the exact order of genetic information that protects chromosomes from ruin. They found that cells age if telomeres are shortened. For example, the first genetic copy of a sheep had shortened telomeres. The cloned animal started to suffer from arthritis at an age that some experts thought was unusually early for a sheep.
Ms. Blackburn and Carol Greider identified the enzyme telomerase. Cells do not die as fast if a lot of telomerase is produced, so aging is slowed. But studies suggest that cancer cells may use telomerase to divide in abnormal ways.
The winners of the Nobel Prize in medicine are all American citizens. Mr. Szostak came to the United States from England. Ms. Blackburn was born in Australia and is also an Australian citizen.
Another woman, an Israeli, is a winner of the Nobel Prize in Chemistry. She is Ada Yonath of the Weitzmann Institute of Science in Rehovot, Israel.
She is sharing the prize with two male researchers. They are Venkatraman Ramakrishnan of the MRC Laboratory of Molecular Biology at Cambridge University in England, and Thomas Steitz of Yale University in New Haven, Connecticut. Mr. Ramakrishnan is a British citizen, and Mr. Steitz is an American.
The Royal Swedish Academy of Sciences is honoring all three researchers for studies of the structure and operation of a kind of cell called a ribosome. The Academy said the three were chosen for having shown what a ribosome looks like and how it operates at the atomic level.
The researchers demonstrated how information in pieces of DNA is translated into the thousands of proteins contained in living matter.
Each researcher worked independently. They made maps that placed hundreds of thousands of atoms in the ribosomes. Some of their work involved X-rays produced by particle accelerators, devices that bring atomic particles into high energies.
The Royal Swedish Academy says the DNA in cells contains the designs for how people, plants and bacteria look and operate. But if there were nothing beyond the DNA in cells, life could not exist.
Ribosomes change the design into living matter of all kinds. They make proteins including oxygen-carrying blood substances, antibodies to protect against disease, and substances that break down sugar.
Many antibiotic medicines currently in use block bacterial ribosomes from action. Bacteria cannot survive without bacterial ribosomes. Each Nobel Prize winner showed how ribosomes tie or bind with antibiotics. The Academy says new medicines could result from the work of the Nobel Prize winners in chemistry.
The Nobel Prize in Physics is going to three scientists who brought the light of knowledge to the subject of light. Half the prize money will go to Charles K. Kao. He did his award-winning work at the Chinese University of Hong Kong, China and at the Standard Telecommunication Laboratories in Britain.
The other two winners are Willard Boyle and George Smith. They did their research at Bell Laboratories in Murray Hill, New Jersey. Mr. Boyle and Mr. Smith will share the remaining prize money equally.
Mr. Kao discovered how to transmit, or send, light signals over long distances through optical glass fibers. He learned to get light to go far enough down a glass fiber to pass on signals. The signals can travel great distances. His work has made possible the development of communications carried around the world by the Internet.
When Mr. Kao began his research 20 years ago, fiber optic materials already existed. But they were short by comparison with today. Mr. Kao's work helped result in the fact that, if lined up, the current optical cables would make a fiber more than 965 million kilometers long.
Mr. Boyle and Mr. Smith invented the charge-coupled device, or CCD. The device can turn light into electrical signals. It provided technology for telescopes, medical images and digital cameras. The Royal Swedish Academy says the researchers' work has made possible great developments in those areas.
For example, doctors are able to use better instruments to examine organs in the body. And, many people now use cameras that do not require film.
Mr. Kao was born in Shanghai, China. He is a citizen of the United States and Britain. Mr. Boyle was born in Canada and is a citizen of Canada and the United States. Mr. Smith is an American.
December 1st was World AIDS Day. A new report about AIDS and the virus responsible for the disease provided some reason to celebrate.
Experts say the number of new H.I.V. infections has fallen by 17 percent since 2001. H.I.V. is short for the human immunodeficiency virus. The experts say estimates of new H.I.V. infections are down by about 15 percent in Africa, south of the Sahara Desert. And, new infections have decreased almost 25 percent in East Asia. In Eastern Europe, the number of new H.I.V. infections has leveled off. But new infections appear to be rising again in some countries.
The numbers come from a report by the UNAIDS program and the World Health Organization. It says H.I.V.-related deaths appear to have reached their highest level in 2004. Since then, deaths have fallen by around ten percent as more people have received treatment.
Experts credit the good news in the report, at least in part, to prevention programs. Yet treatments and population growth mean that more people than ever are living with H.I.V. The latest estimates say almost 33,500,000 have the virus. There were two million AIDS-related deaths last year, and 2,700,000 new infections.
This SCIENCE IN THE NEWS was written by Jerilyn Watson and Caty Weaver. Our producer was Brianna Blake. I'm Doug Johnson.
And I'm Mario Ritter. Listen again next week for more news about science in Special English on the Voice of America.
telomere: either of the sections of DNA occurring at the ends of a chromosome 端区（端粒）
enzyme: any of numerous proteins or conjugated proteins produced by living organisms and functioning as biochemical catalysts 酶
telomerase: an enzyme that is found in the telomeres of chromosomes in germ cells, stem cells, and most cancer cells and that preserves the length of telomeres across cell divisions 末端酶
deoxyribonucleic acid: DNA 脱氧核糖核酸
arthritis: inflammation of a joint, usually accompanied by pain, swelling, and stiffness, and resulting from infection, trauma, degenerative changes, metabolic disturbances, or other causes; it occurs in various forms, such as bacterial arthritis, osteoarthritis, or rheumatoid arthritis 关节炎
ribosome: a minute round particle composed of RNA and protein that is found in the cytoplasm of living cells and serves as the site of assembly for polypeptides encoded by messenger RNA 核糖体
Chinese Nobel Winner 诺贝尔奖得主高锟
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