Posts about nobel laureate

The Nobel Prize in Physics 2009

The 2009 Nobel Prize in Physics honors three scientists, who have had important roles in shaping modern information technology, with one half to Charles Kuen Kao and with Willard Sterling Boyle and George Elwood Smith sharing the other half. Kao’s discoveries have paved the way for optical fiber technology, which today is used for almost all telephony and data communication. Boyle and Smith have invented a digital image sensor – CCD, or charge-coupled device – which today has become an electronic eye in almost all areas of photography. The Nobel prize site includes great information on the science behind the research that has been honored:

The first ideas of applications of light guiding in glass fibers (i.e. small glass rods) date from the late 1920’s. They were all about image transmission through a bundle of fibers. The motivation was medicine (gastroscope), defense (flexible periscope, image scrambler) and even early television. Bare glass fibers were, however, quite leaky and did not transmit much light. Each time the fibers were touching each other, or when the surface of the fibers was scratched, light was led away from the fibers. A breakthrough happened in the beginning of the 1950’s with the idea and demonstration that cladding the fibers would help light transmission, by facilitating total internal reflection.

Optical communication of today has reached its present status thanks to a number of breakthroughs. Light emitting diodes (LEDs) and especially diode lasers, first based on GaAs (800-900 nm) and later on InGaAsP (1-1.7 m), have been essential. The optical communication window has evolved from 870 nm to 1.3 m and, finally, to 1.55 m where fiber losses are lowest. Gradient-index fibers were used in the first optical communication lines. However, when moving towards longer wavelengths and longer communication distances, single-mode fibers have become more advantageous.

Nowadays, long-distance optical communication uses single mode fibers almost exclusively, following Kao’s vision. The first such systems used frequent electronic repeaters to compensate for the remaining losses. Most of these repeaters have now been replaced by optical amplifiers, in particular erbium-doped fiber amplifiers. Optical communication uses wavelength division multiplexing with different wavelengths to carry different signals in the same fiber, thus multiplying the transmission rate. The first non-experimental optical fiber links were installed in 1975 in UK, and soon after in the US and in Japan. The first transatlantic fiber-optic cable was installed in 1988.

Related: How telephone echoes lead to digital cameras2007 Nobel Prize in Physics2006 Nobel Prize in Physicsposts on Nobel laureates

2009 Nobel Prize in Chemistry: the Structure and Function of the Ribosome

graphic image of the components of a cellCross section of a cell by the Royal Swedish Academy of Sciences. A ribosome is about 25 nanometters (a millionth of a millimeter) in size. A cell contains tens of thousands of ribosomes.

The Nobel Prize in Chemistry for 2009 awards studies of one of life’s core processes: the ribosome’s translation of DNA information into life. Ribosomes produce proteins, which in turn control the chemistry in all living organisms. As ribosomes are crucial to life, they are also a major target for new antibiotics.

This year’s Nobel Prize in Chemistry awards Venkatraman Ramakrishnan, Thomas A. Steitz and Ada E. Yonath for having showed what the ribosome looks like and how it functions at the atomic level. All three have used a method called X-ray crystallography to map the position for each and every one of the hundreds of thousands of atoms that make up the ribosome.

Inside every cell in all organisms, there are DNA molecules. They contain the blueprints for how a human being, a plant or a bacterium, looks and functions. But the DNA molecule is passive. If there was nothing else, there would be no life.

The blueprints become transformed into living matter through the work of ribosomes. Based upon the information in DNA, ribosomes make proteins: oxygen-transporting haemoglobin, antibodies of the immune system, hormones such as insulin, the collagen of the skin, or enzymes that break down sugar. There are tens of thousands of proteins in the body and they all have different forms and functions. They build and control life at the chemical level.

Related: The Nobel Prize in Chemistry 20082007 Nobel Prize in Chemistry2006 Nobel Prize in Chemistryposts on chemistrybasic research posts

Details from the Nobel Prize site (which continues to do a great job providing scientific information to the public openly).
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2009 Nobel Prize in Physiology or Medicine

This year’s Nobel Prize in Physiology or Medicine is awarded to three scientists who have solved a major problem in biology: how the chromosomes can be copied in a complete way during cell divisions and how they are protected against degradation. The Nobel Laureates have shown that the solution is to be found in the ends of the chromosomes – the telomeres – and in an enzyme that forms them – telomerase.

The long, thread-like DNA molecules that carry our genes are packed into chromosomes, the telomeres being the caps on their ends. Elizabeth Blackburn and Jack Szostak discovered that a unique DNA sequence in the telomeres protects the chromosomes from degradation. Carol Greider and Elizabeth Blackburn identified telomerase, the enzyme that makes telomere DNA. These discoveries explained how the ends of the chromosomes are protected by the telomeres and that they are built by telomerase.

If the telomeres are shortened, cells age. Conversely, if telomerase activity is high, telomere length is maintained, and cellular senescence is delayed. This is the case in cancer cells, which can be considered to have eternal life. Certain inherited diseases, in contrast, are characterized by a defective telomerase, resulting in damaged cells. The award of the Nobel Prize recognizes the discovery of a fundamental mechanism in the cell, a discovery that has stimulated the development of new therapeutic strategies.

Scientists began to investigate what roles the telomere might play in the cell. Szostak’s group identified yeast cells with mutations that led to a gradual shortening of the telomeres. Such cells grew poorly and eventually stopped dividing. Blackburn and her co-workers made mutations in the RNA of the telomerase and observed similar effects in Tetrahymena. In both cases, this led to premature cellular ageing – senescence. In contrast, functional telomeres instead prevent chromosomal damage and delay cellular senescence. Later on, Greider’s group showed that the senescence of human cells is also delayed by telomerase. Research in this area has been intense and it is now known that the DNA sequence in the telomere attracts proteins that form a protective cap around the fragile ends of the DNA strands.

Many scientists speculated that telomere shortening could be the reason for ageing, not only in the individual cells but also in the organism as a whole. But the ageing process has turned out to be complex and it is now thought to depend on several different factors, the telomere being one of them. Research in this area remains intense.

The 3 awardees are citizens of the USA; two were born elsewhere.
Read more about their research at the Nobel Prize web site.

Molecular biologist Elizabeth Blackburn–one of Time magazine’s 100 “Most Influential People in the World” in 2007–made headlines in 2004 when she was dismissed from the President’s Council on Bioethics after objecting to the council’s call for a moratorium on stem cell research and protesting the suppression of relevant scientific evidence in its final report.

Related: Nobel Prize in Physiology or Medicine 20082007 Nobel Prize in Physiology or Medicine2006 Nobel Prize in Physiology or Medicine

Webcast of Dr. Elizabeth Blackburn speaking at Google:
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Norman E. Borlaug 1914-2009

The Father Of the Green Revolution

Norman E. Borlaug, 95, an American plant pathologist who won the Nobel Peace Prize in 1970 for starting the “Green Revolution” that dramatically increased food production in developing nations and saved countless people from starvation, died Saturday at his home in Dallas.

“More than any other single person of this age, he has helped provide bread for a hungry world,” the Nobel committee said in honoring him. “Dr. Borlaug has introduced a dynamic factor into our assessment of the future and its potential.”

In his lecture accepting the Nobel Prize, he said an adequate supply of food is “the first component of social justice. . . . Otherwise there will be no peace.”

In 1977, Dr. Borlaug received the Medal of Freedom, the highest civilian honor of the U.S. government.

Billions Served: Norman Borlaug interviewed by Ronald Bailey

As a matter of fact, Mother Nature has crossed species barriers, and sometimes nature crosses barriers between genera–that is, between unrelated groups of species. Take the case of wheat. It is the result of a natural cross made by Mother Nature long before there was scientific man. Today’s modern red wheat variety is made up of three groups of seven chromosomes, and each of those three groups of seven chromosomes came from a different wild grass. First, Mother Nature crossed two of the grasses, and this cross became the durum wheats, which were the commercial grains of the first civilizations spanning from Sumeria until well into the Roman period. Then Mother Nature crossed that 14-chromosome durum wheat with another wild wheat grass to create what was essentially modern wheat at the time of the Roman Empire.

Durum wheat was OK for making flat Arab bread, but it didn’t have elastic gluten. The thing that makes modern wheat different from all of the other cereals is that it has two proteins that give it the doughy quality when it’s mixed with water. Durum wheats don’t have gluten, and that’s why we use them to make spaghetti today. The second cross of durum wheat with the other wild wheat produced a wheat whose dough could be fermented with yeast to produce a big loaf. So modern bread wheat is the result of crossing three species barriers, a kind of natural genetic engineering.

I see no difference between the varieties carrying a BT gene or a herbicide resistance gene, or other genes that will come to be incorporated, and the varieties created by conventional plant breeding. I think the activists have blown the health risks of biotech all out of proportion.

the data that’s put out by the World Health Organization and [the U.N.’s Food and Agriculture Organization], there are probably 800 million people who are undernourished in the world. So there’s still a lot of work to do.

I am a bit more cautious about supporting genetic engineering in our food supply but I agree with him that we need to remain focused on the lives of hundreds of millions of hungry people (which is far too often ignored). I am worried about the risks to the environment and human health. I am also worried about the concentration of food plants in a greatly reduced genetic varieties that are more productive in general but increase the risks of massive food failures (due to limited genetic varieties).

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Roger Tsien Lecture On Green Florescent Protein

Nobel Laureate Roger Tsien discusses his research on green florescent protein. From the Nobel Prize web site:

n the 1960s, when the Japanese scientist Osamu Shimomura began to study the bioluminescent jelly-fish Aequorea victoria, he had no idea what a scientific revolution it would lead to. Thirty years later, Martin Chalfie used the jellyfish’s green fluorescent protein to help him study life’s smallest building block, the cell.

when Anton van Leeuwenhoek invented the microscope in the 17th century a new world opened up. Scientists could suddenly see bacteria, sperm and blood cells. Things they previously did not know even existed. This year’s Nobel Prize in Chemistry rewards a similar effect on science. The green fluorescent protein, GFP, has functioned in the past decade as a guiding star for biochemists, biologists, medical scientists and other researchers.

This is where the third Nobel Prize laureate Roger Tsien makes his entry. His greatest contribution to the GFP revolution was that he extended the researchers’ palette with many new colours that glowed longer and with higher intensity.

To begin with, Tsien charted how the GFP chromophore is formed chemically in the 238-amino-acid-long GFP protein. Researchers had previously shown that three amino acids in position 65–67 react chemically with each other to form the chromosphore. Tsien showed that this chemical reaction requires oxygen and explained how it can happen without the help of other proteins.

With the aid of DNA technology, Tsien took the next step and exchanged various amino acids in different parts of GFP. This led to the protein both absorbing and emitting light in other parts of the spectrum. By experimenting with the amino acid composition, Tsien was able to develop new variants of GFP that shine more strongly and in quite different colours such as cyan, blue and yellow. That is how researchers today can mark different proteins in different colours to see their interactions.

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The Nobel Prize in Chemistry 2008

The Nobel Prize in Chemistry 2008 is evenly shared by Osamu Shimomura, Boston University Medical School, USA; Martin Chalfie, Columbia University, New York, USA and Roger Y. Tsien, University of California, San Diego, USA for discovery and work with glowing green fluorescent protein.

The remarkable brightly glowing green fluorescent protein, GFP, was first observed in the beautiful jellyfish, Aequorea victoria in 1962. Since then, this protein has become one of the most important tools used in contemporary bioscience. With the aid of GFP, researchers have developed ways to watch processes that were previously invisible, such as the development of nerve cells in the brain or how cancer cells spread.

Tens of thousands of different proteins reside in a living organism, controlling important chemical processes in minute detail. If this protein machinery malfunctions, illness and disease often follow. That is why it has been imperative for bioscience to map the role of different proteins in the body.

This year’s Nobel Prize in Chemistry rewards the initial discovery of GFP and a series of important developments which have led to its use as a tagging tool in bioscience. By using DNA technology, researchers can now connect GFP to other interesting, but otherwise invisible, proteins. This glowing marker allows them to watch the movements, positions and interactions of the tagged proteins.

Researchers can also follow the fate of various cells with the help of GFP: nerve cell damage during Alzheimer’s disease or how insulin-producing beta cells are created in the pancreas of a growing embryo. In one spectacular experiment, researchers succeeded in tagging different nerve cells in the brain of a mouse with a kaleidoscope of colors.

Osamu Shimomura
, a Japanese citizen, was born 1928 in Kyoto, Japan. He received his Ph.D. in organic chemistry 1960 from Nagoya University, Japan. first isolated GFP from the jellyfish Aequorea victoria, which drifts with the currents off the west coast of North America. He discovered that this protein glowed bright green under ultraviolet light.

Martin Chalfie demonstrated the value of GFP as a luminous genetic tag for various biological phenomena. In one of his first experiments, he coloured six individual cells in the transparent roundworm Caenorhabditis elegans with the aid of GFP.

Roger Y. Tsien contributed to our general understanding of how GFP fluoresces. He also extended the colour palette beyond green allowing researchers to give various proteins and cells different colours. This enables scientists to follow several different biological processes at the same time.

Related: 2007 Nobel Prize in ChemistryNobel Laureate Initiates Symposia for Student ScientistsNobel Prize in Chemistry (2006)Webcasts by Chemistry and Physics Nobel Laureates

Nobel Prize in Physiology or Medicine 2008

photos of Harald zur Hausen, Françoise Barré-Sinoussi and Luc Montagnier

The Nobel Prize in Physiology or Medicine for 2008 with one half to Harald zur Hausen for his discovery of “human papilloma viruses causing cervical cancer” and the other half jointly to Françoise Barré-Sinoussi and Luc Montagnier for their discovery of “human immunodeficiency virus.”

Harald zur Hausen went against current dogma and postulated that oncogenic human papilloma virus (HPV) caused cervical cancer, the second most common cancer among women. He realized that HPV-DNA could exist in a non-productive state in the tumours, and should be detectable by specific searches for viral DNA. He found HPV to be a heterogeneous family of viruses. Only some HPV types cause cancer. His discovery has led to characterization of the natural history of HPV infection, an understanding of mechanisms of HPV-induced carcinogenesis and the development of prophylactic vaccines against HPV acquisition.

Françoise Barré-Sinoussi and Luc Montagnier discovered human immunodeficiency virus (HIV). Virus production was identified in lymphocytes from patients with enlarged lymph nodes in early stages of acquired immunodeficiency, and in blood from patients with late stage disease. They characterized this retrovirus as the first known human lentivirus based on its morphological, biochemical and immunological properties. HIV impaired the immune system because of massive virus replication and cell damage to lymphocytes. The discovery was one prerequisite for the current understanding of the biology of the disease and its antiretroviral treatment.

Related: 2007 Nobel Prize in Physiology or Medicine2006 Nobel Prize in Physiology or Medicine

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Nobel Laureate Initiates Symposia for Student Scientists

The video shows a portion of Oliver Smithies’ Nobel acceptance lecture. See the rest of the speech, and more info, on the Nobel Prize site.

As an undergraduate student at Oxford University in the 1940s, Oliver Smithies attended a series of lectures by Linus Pauling, one of the most influential chemists of the 20th century. It was a powerful experience, one that sparked the young scientist’s ambitions and helped launch his own eminent career.

“It was tremendously inspiring,” says Smithies, one of three scientists who shared the Nobel Prize in Medicine in 2007. “People were sitting in the aisles to listen to him.”

Now Smithies, who was a genetics professor at the University of Wisconsin-Madison from 1960-88, is taking it upon himself to expose a new generation of undergraduates to this sort of experience. Using the prize money that came with his Nobel Prize, Smithies is funding symposia at all four universities he has been affiliated with throughout his scientific career: Oxford, the University of Toronto, UW-Madison and the University of North Carolina, where he is currently the Excellence Professor of Pathology and Laboratory Medicine. Each university will receive about $130,000 to get things started.

“He wants the symposium to be a day when we bring the very best in biology to campus to interact with the students,” says geneticist Fred Blattner, who is in charge of organizing the symposium at UW-Madison and who collaborated with Smithies when their careers paths overlapped in Wisconsin.

The first of two speakers at the UW-Madison’s inaugural Oliver Smithies Symposium will be Leroy Hood, director of the Institute for Systems Biology, located in Seattle. Hood is a pioneer of high-throughput technologies and was instrumental in developing the technology used to sequence the human genome. More recently, Hood has focused his efforts on systems biology, the field of science in which researchers create computer models to describe complex biological processes, such as the development of cancer in the body. He is also at the forefront of efforts to use computer models to help doctors tailor drugs and dosages to an individual’s genetic makeup.
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Challenging the Science Status Quo

Challenging Science

When scientists question facets of existing theories or propose new ones, they present the best evidence available and make the strongest arguments they can to their colleagues. Colleagues in turn challenge that evidence and reasoning. The rigor of this process is what makes science such a powerful tool.

Lynn Margulis wrote a paper, “The Origin of Mitosing Eukaryotic Cells,” which argued that eukaryotic cells – those with a true nucleus – arose when cells with no nucleus symbiotically incorporated other such cells to make new cells that could perform more functions. The paper was rejected by many journals, and when eventually published by The Journal of Theoretical Biology it was highly criticized. Margulis spent decades defending her work, but scientists now accept her suggested mechanism through which organelles such as mitochondria and chloroplasts evolved. Her suggestions about other organelles have not stood up to experimental tests, and are not as widely accepted.

In 1982, Stanley Prusiner published an article on his research into scrapie – a disease in sheep related to Creutzfeldt-Jakob disease – which argued that the infectious agent was not a virus but a protein, which Prusiner called a “prion”. Because no one had heard of a protein replicating without a nucleic acid like DNA or RNA, many virologists and scrapie researchers reacted to the article with incredulity. When the media picked up the story, “the personal attacks of the naysayers at times became very vicious,” according to Prusiner. However, his critics failed to find the nucleic acid they were sure existed, and less than two years later, Prusiner’s lab had isolated the protein. Subsequent research provided even more support for prions, and in 1997 Prusiner was awarded the Nobel Prize in Physiology or Medicine.

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Science Education in the 21st Century

Photo of Dr. Carl Wieman

Science Education in the 21st Century: Using the Tools of Science to Teach Science podcast by Dr. Carl Wieman, recipient of the Nobel Prize in Physics in 2001. Also received the first NSF Distinguished teaching Scholars award (NSF’s “highest honor for excellence in both teaching and research”) and the National Professor Of The Year (CASE and Carnegie Foundation).

Dr. Carl Wieman, recipient of the Nobel Prize in Physics in 2001, discusses the failures of traditional educational practices, even as used by “very good” teachers, and the successes of some new practices and technology that characterize this more effective approach. Research on how people learn science is now revealing how many teachers badly misinterpret what students are thinking and learning from traditional science classes and exams.

However, research is also providing insights on how to do much better. The combination of this research with modern information technology is setting the stage for a new more effective approach to science education based on using the tools of science. This can provide a relevant and effective science education to all students.

Podcast recording 21 Nov 2005 at the University of British Columbia.

Text of March 15, 2006 Dr. Wieman testimony to the US House of Representatives Science Committee.

Nobel Laureate Joins UBC to Boost Science Education

via: Maintaining scientific humility