Hard disk pioneers win physics Nobel

Hard disk pioneers win physics Nobel
France's Albert Fert and Germany's Peter Gruenberg won the 2007 Nobel Prize for physics on Tuesday for a breakthrough in nanotechnology that lets huge amounts of data be squeezed into ever-smaller spaces. Gadgets from powerful laptops to iPods owe their existence to the discovery. The 10-million Swedish crown ($1.54 million) prize, awarded by The Royal Swedish Academy of Sciences, recognized the pair for revealing a physical effect called giant magnetoresistance. "It is thanks to this technology that it has been possible to miniaturize hard disks so radically in recent years," the academy said in a statement. Giant magnetoresistance -- GMR for short -- works through a large electrical response to a tiny magnetic input. When atoms are laid down on a hard disk in ultra-thin layers, they interact differently than when spread out more. This makes it possible to pack more data on disks. Surrounded by journalists in Paris soon after learning of his award, the 69-year-old Fert started chatting with some youngsters near the CNRS research centre he co-founded. "You like physics?" he asked, telling them he had just won the Nobel prize. "If you are able to listen to music on your MP3 player, it is a bit thanks to what I've done." Fert and Gruenberg, 68, figured out how to stack nanometer-thin layers of magnetic and non-magnetic atoms to produce the GMR effect. "The story of the GMR effect is a very good demonstration of how a totally unexpected scientific discovery can give rise to completely new technologies and commercial products," the Nobel committee wrote. SCIENCE FICTION It works because of a property called spin. Electrons -- the charged particles within atoms -- "spin" in different directions under various circumstances, producing the changes in resistance that are used to store data. "It is the thing that has made iPods possible and anything that requires lots of data storage, like YouTube," said Chris Marrows, a physicist at Leeds University who specializes in a branch of technology known as spintronics. Thanks to advances based on GMR, a typical laptop computer now holds about 100 gigabytes of data. That is equal to the information contained in a kilometer-long (3,280-foot) bookshelf, roughly an entire library floor of academic journals. Ben Murdin, a physics professor at the University of Surrey in southeast England, described the technology as something practically out of a work of science fiction. "A computer hard disk reader that uses a GMR sensor is equivalent to a jet flying at a speed of 30,000 kilometers (19,500 miles) per hour ... at a height of just one meter above the ground, and yet being able to see and catalogue every single blade of grass it passes over," Murdin said. Fert and Gruenberg each made the discovery independently of the other. They shared the 2007 Japan Prize for their work. As Nobel physics laureates, the two join the ranks of some of the greatest names in science, including Albert Einstein, Marie Curie, Niels Bohr and Wilhelm Rontgen. Rontgen won the first prize in 1901 for discovering X-rays. Gruenberg said the award was "slightly" expected. "But not completely because then I would have worn a tie," he told reporters, sporting an open-neck shirt. "What is my first reaction? Well, I can't remember, I was stunned." German Chancellor Angela Merkel, a physicist herself, said: "It is a great honor ... The prize shows how fundamental research can lead to technical, practical uses." Merkel's French counterpart, President Nicolas Sarkozy, portrayed the award as a coup for Europe. "It is European research which is crowned," Sarkozy said in a statement. He said Fert was among the great minds who led the way forward for French development and glory. This was the second of this year's crop of Nobel prizes, which are handed out annually for achievements in science, literature, economics and peace. All but one of the prizes were established in the will of 19th century dynamite millionaire Alfred Nobel. The economics award was established by Sweden's central bank in 1968. (Additional reporting by Maggie Fox in Washington, Simon Johnson, Sarah Edmonds, and Emma Bengtsson in Stockholm, and Michael Kahn in London and Thierry Leveque in Paris)

Racial Disparities Affect Breast Cancer Treatment

Racial Disparities Affect Breast Cancer Treatment

White Women More Likely to Receive Chemotherapy, Hormone Therapy

A new study suggests African-American women with breast cancer lag behind their white counterparts White Women More Likely to Receive Chemotherapy, Hormone Therapy

By all accounts, breast cancer survivor Yvonne Durham was lucky.

"It was the Friday before Mother's Day of 1992," she said. "I had had a biopsy of a lump in my left breast. And a man walked into the room and told me I had breast cancer."

"I was shocked. I was just totally shocked."

After her diagnosis, Durham began a long road of treatment that included surgery, radiation therapy and hormone therapy with the drug Tamoxifen.

The treatment may be a major reason she is alive today. But a new study suggests that black women like Durham may be three times less likely to receive chemotherapy and five times less likely to receive Tamoxifen than their white counterparts.

"I had an excellent doctor, and in my heart I don't want to think that black women get different treatment," said Durham, who added that she was pleased with the level of care she received. "But sometimes I've noticed that doctors tell their white patients more than they tell us."

And when it comes to breast cancer, knowledge is key.

"For example, I had a white girlfriend with breast cancer who asked me if I was Her2 receptor positive. I didn't know what she was talking about," Durham said.

"My friend was no more educated than I was. But these receptors were explained to her. Staging was explained to her. I knew I had a good doctor, but I didn't know anything about these things."

White Women More Likely to Get Chemo

Whether because of breakdowns in doctor-patient communication or some other factor, disparities between the treatment of black women and white women with breast cancer exist, according a new study published today.

Researchers at the University of Michigan and Wayne State University found that among women with breast cancer that had spread to lymph nodes, white women were three times as likely to receive adjuvant chemotherapy and almost five times as likely to receive Tamoxifen, a common hormonal drug for breast cancer.

The study examined medical records from 651 women diagnosed with breast cancer at a major university hospital and cancer center in Detroit from 1990 to 1996. Of the women, 242 were white and 388 were black.

Previous studies had also shown differences in treatment rates between blacks and whites, but discerning the reasons for the differences was often difficult.

Blacks, for example, have been found to have a higher percentage of breast cancers that are "estrogen receptor negative," meaning they will not respond well to traditional hormone treatments such as Tamoxifen. Lower socioeconomic status, later stage at the time of diagnosis and several other factors had also been cited in the past as a possible reason for the disparities.

The researchers looked at women who had both "local stage"  cancers confined to the breast  as well as "regional stage"  cancers that had either spread to lymph nodes or physically extended outside the breast.

They then catalogued the types of treatment used. This included types of initial treatment such as mastectomy or breast-conserving surgery (such as lumpectomy) plus radiation, as well as "adjuvant," or supplemental, treatments like chemotherapy and hormone therapy with the drug Tamoxifen.

"Our goal was to do a comprehensive analysis, looking at factors such as socioeconomic status, co-morbidities, access to care, age, insurance status and others," said lead study author Mousumi Banerjee, a researcher at the University of Michigan School of Pubic Health. "When we adjusted for these, there was still a difference in the group with regional disease."

In women with regional-stage disease, whites were more than three times as likely to have received adjuvant chemotherapy and more than 4½ times more likely to have received adjuvant Tamoxifen. Banerjee said, "They were definitely noticeable differences."

Signs of Hope

Although the differences in treatment were cause for concern, there were some encouraging signs as well in the data.

Previous studies had shown differences between blacks and whites in rates of "breast-conserving" surgeries such as lumpectomy and adjuvant radiation  differences that were not seen in this study. There were also no significant differences seen in rates of Tamoxifen or chemotherapy use for local-stage disease.

"Usually surgery is part of the treatment," said Dr. Beverly Moy, a medical oncologist at the Massachusetts General Hospital. "But for some cancers, it is completely equivalent to do mastectomy versus lumpectomy plus radiation. Given an option, most women would choose keeping their breast. So it was nice to see similar rates of mastectomy and breast-conserving therapy (between blacks and whites) in this study."

Why the Difference?

Most experts were not surprised by the results of the study, but stated that figuring out why the differences existed would be difficult.

"It is sometimes very difficult to determine whether disparities are due to race or other factors," said Moy. "But in my opinion, race is a very important factor to consider."

"It is probably multifactorial," said Dr. Herbert Smitherman Jr., assistant dean of community and urban health at the Wayne State School of Medicine in Detroit. "The choices that people make are clearly a composite expression of their social and cultural circumstances, their conditions of living and the conditions of their community."

Smitherman adds that one factor may be physicians' ability to communicate effectively with their patients.

"There has been some literature showing that physicians' perception of the patient may be affected by race," said Smitherman. "This includes perceptions of patients' ability to understand choices, a sense of affiliation with patients and the ability to engage patients."

"When we walk into a patient's room, it's not like there's pixie dust and we leave everything back at the door."

Kendra Schwartz, study co-author and professor of family medicine at Wayne State, said this possibility highlights the need for physicians to be more cognizant of their interactions with members of a different race.

"We really need to ask the patient explicitly  'what have you been told? What are your feelings about the treatment options?'" she said. "There are often people who initially don't want chemotherapy because of side effects, but if they are educated about how therapies improve survival, things can change."

Breaking Down the Walls

On the other side of the patient-doctor relationship, some worry that a history of distrust of the medical establishment among members of the black community may also be affecting patients' medical decision-making.

"There is some, perhaps appropriate, distrust of the medical community," said Smitherman. "It's been shaped from the Tuskegee study on down, and this is passed down through the generations," he added, referring to a notorious study in which black men were not informed of their diagnosis of syphilis, and in some cases, were denied treatment.

"All sorts of perceptions in society can affect the relationship with the physician. Patients ask themselves, 'can I trust this person with my life?'"

Breast cancer survivor Durham said she believes there are additional cultural issues that may play a role in patients' abilities to make the right choices.

"Some women, especially in our [black] culture and especially older women, may think of doctors as such an authority figure, they are afraid to ask questions and afraid they may sound stupid."

One possible solution is that patients diagnosed with breast cancer particularly blacks need to take a more active role in educating themselves and advocating for their choices.

"I would say, you're [the patient is] going to have to educate yourself," Smitherman said. "Part of being in the health-care system is that you have to get knowledge. You'll have to get on the Internet and look up stuff, and come prepared when you come into the physician's office."

"Write down your questions. Just like when you go to your accountant, or church, or a talk, be prepared ahead of time."

Durham agreed that patients need to have the ability to take ownership over their disease. Today she works as a program specialist for Encore Plus, an outreach and education program for breast and cervical cancer targeted at minority and medically underserved women.

"When I'm out in the [black] community talking about breast cancer, I tell people, 'we have to be our own best advocates.'"

"Patients need to talk to other women that have the disease, go into a support group setting. Where you lack understanding, search for it until you get it." 

Liquid Drops Defy Gravity, Travel Uphill

Liquid Drops Defy Gravity, Travel Uphill

Gravity-defying drops of liquid can travel uphill if the surface they are sitting on is shaken up and down vigorously enough, a new study finds.

If you've ever looked out a window on a rainy day, you've probably noticed that small drops of water tend to stay where they fall, while big ones roll down the glass. Small drops stay still because the surface tension holding them up is balanced against the force of gravity pulling them down. But for bigger drops, gravity overwhelms the surface tension force and causes the drop to slide down.

Mathematicians at the University of Bristol have shown that not only can small drops withstand the force of gravity, they can completely defy it. Even on an incline as steep as 85 degrees (almost perpendicular to the ground), small drops can travel uphill if the surface vibrates strongly enough.

"As the shaking plate rises, the drop is compressed, while it bulges upward as the plate falls," explained researcher Jens Eggers. "If the shaking is vigorous enough to overcome the surface tension experienced as the drop is compressed, the drop will tend to lean forward, producing a net force which drives the drop uphill."

Drops must be just the right size, as large drops will tend to break apart under the forces applied to them. Similarly, the liquid's viscosity is important: Pure water droplets aren't strong enough to hold together and would break apart, and liquids that are too thick will move too slowly. The results will be published online this week in the journal Physical Review Letters.

Scientists have previously used extremely hot surfaces to force water to move up an incline.

Understanding how to move these tiny droplets could help improve certain processes, like arranging pieces of DNA, said Egger's colleague Philippe Brunet. 

Monumental Human Voyages Revealed by Obscure Tool

Monumental Human Voyages Revealed by Obscure Tool

Big news about the adze this week.

Your first question might be, of course, what the heck is an adze? We live and breathe "ads," as in advertisements, but "adze?"

An adze is tool that looks like an ax but with the blade turned at a right angle.

It's a handy tool. Swing it overhead and down in an arc on a piece of wood and gouge out a big chunk with one fell swoop, or plane down the surface of a finished wooden object with finer strokes.

Obviously, it takes skill to use an adze given the dangers of taking off a toe, a finger or ending your sex life.

Although one might be hard pressed to find an adze today (unless you're a woodworker), adzes have been part of human history ever since people began making things.

During the Stone Age, early humans chipped away at hunks of rock to make hand-held adzes which were probably used to butcher animals or fashion other tools. The Egyptians refined the adze by making it from metal and then mounting the blade on a wooden handle. Other cultures made their adzes out of whatever was at hand—shell, wood, bone—anything that would slice and dice.

The adze can also be a key to mapping ancient human migrations because it's portable.

This week, Kenneth Collerson and Marshall Weisler of the University of Queensland, Australia, announced they have traced the sea voyages of adzes, and therefore people, into the far reaches of the eastern Pacific Ocean 4,000 year ago.

Peopling the Pacific was an adventure of mythic proportions. For centuries, no one believed that the Pacific Islanders got there under their own steam (or sail). Instead, the story went, these "primitive" people must have been out for a leisurely Sunday sail when the seas shifted and a coral atoll rose up and beached their boat, forcing them to settle down and make do.

But research tracing pottery types, canoe designs, fish hooks and common language eventually demonstrated that long ago people must have been voluntarily crisscrossing the vast Pacific in search of new homes. More recently, experimental voyages in replica canoes with sails also showed that long sea voyages were not only possible, but probable, even 4,000 years ago.

Collerson and Weisler have underscored the seafaring skills of these early people by analyzing the origins of trace elements in the basalt rock of stone adzes found across the remote Eastern Polynesian Islands, specifically the Tuamotu Islands, where there is no endemic basalt.

The researchers found that the basalt used in adzes came from five different atolls ringing the Tuamotus, and each atoll is thousands of kilometers away.

For example, one adze originated on Kasho'olawe, Hawaii, more than 4,000 kilometers away. There are no such ancient adzes on Kasho'olawe, but the basalt is easily found along the shoreline where modern sailors still conduct ceremonies before long seas voyages.

Long ago, Hawaiians must have had adzes on board as they set sail for the great unknown. Or maybe they casually pitched a few beach stones into the bottom of the boat for ballast and then threw them out after reaching Eastern Polynesia.

The adzes, evidence of a monumental journey, might then have been carved by Tuamotu Islanders who were smart enough to figure out what to do with the garbage of passing tourists.

Why do migratory birds fly in a V-formation?

Why do migratory birds fly in a V-formation?

Bruce Batt, chief biologist for the conservation group Ducks Unlimited, based in Memphis, Tenn., explains. 

The linear flight formations of migratory birds are called echelons. The V and the J structures are typical and are the most readily recognized flock echelons, but other variations also occur. Studies of several species have shown that a true V-shaped echelon is, in fact, less common than a J formation is. There are two well-supported and complementary explanations for why birds fly in formation. One is to conserve energy by taking advantage of the upwash vortex fields created by the wings of the birds in front. The other is to facilitate orientation and communication among the birds. These explanations are not mutually exclusive, and both have been backed by a variety of studies. The relative importance of each undoubtedly shifts as various factors, such as the season of the year or the purpose of individual flights, change. During local feeding flights, for example, energy conservation is probably much less important than careful orientation and collision avoidance are. During long-distance migration, orientation and communication remain necessary, but there is also much to be gained for each bird in the flock by optimizing its position to conserve energy. 

Fluid dynamics and energy wave configuration calculations have been used to test predictions of where birds should position themselves in relation to others to conserve the most energy as they travel through the air. Analyses of flock formations using photography have measured bird positions and found them to almost always be located such that they gain some energetic advantage. The animals are not very often in the expected optimal location, however, indicating that other factors also influence position in the formation.

Knowledge of birds visual axes, "blind spots" and field of vision have allowed researchers to pinpoint the best locations for birds within a flock to maintain optimal visual positioning. Actual positions of the animals are usually positively related to these predictions but are, again, not always optimal. Studies have categorized the positions of birds and found that some individuals take positions that are most closely predicted to satisfy the energy conservation hypothesis; others are in better visual contact positions; and still others are not apparently responding to either benefit or are in a position that should gain some advantage from both benefits. 

The leaders of formations change from time to time, but the causes, frequency and characteristics of these changes have not yet been determined. Sustained observation from the ground of flocks covering great distances in the air is very difficult. There are plenty of intuitive predictions about leader choice that quickly come to mind relative to the age, experience, sex, condition and social status of the leaders, but researchers have not figured out how to overcome the prohibitive logistic issues to test them. Some scientists have trained birds to fly in formation with small aircraft; perhaps their experiences will yield opportunities to test these ideas.