Dark Matter Mystery Deepens

Dark Matter Mystery Deepens in Cosmic "Train Wreck"

This multi-wavelength image of Abell 520 shows the aftermath of a complicated collision of galaxy clusters, some of the most massive objects in the Universe. In this image, the hot gas as detected by Chandra is colored red. Optical data from the Canada-France-Hawaii and Subaru telescopes shows the starlight from the individual galaxies (yellow and orange). The location of most of the matter in the cluster (blue) was also found using these telescopes, by tracing the subtle light-bending effects on distant galaxies. This material is dominated by dark matter.

Abell 520 – click for 792×792 image

Additional information: here, here, here, here, here

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Readings, 27 August 2007

The text following each item is quoted material, except for editorial comments, which are in color.

Climate change and global warming

Last time around was all about physics and astronomy. This time it's about climate change and global warming, with special emphasis on climate modeling and the politics surrounding these things.

Catching Up With Climate

From the evidence of tree rings, the last 50 years were the warmest half-century in 1,300 years. Eleven of the past 12 years are the hottest on record since reliable record-keeping began in 1850; since 1870, sea level has risen some eight inches worldwide, and the rate is accelerating; since 1900, glaciers have shrunk 80 percent, and polar ice is melting fast; concentrations of carbon dioxide are 35 percent higher than preindustrial levels.

To lead off, we have an article on climate models, some of the people who contribute to them, and the diverse factors that enter into them.

A new dawn for climate prediction

Scientists must develop new, more adaptive approaches to predicting and monitoring climate, say climate modellers from the University of Exeter. In a 'perspectives' article published in leading journal Science, Professor Peter Cox and Professor David Stephenson argue that new prediction tools are required to help us to limit and adapt to climate change.

Here we have a brief overview of a Perspectives article, recently published in Science, about some shortcomings of current climate models with respect to usefulness in making policy decisions. This is the full article, but a subscription is required to read it all.

Cloudy Crystal Balls

Climate models may never produce predictions that agree with one another, even with dramatic improvements in their ability to imitate the physics and chemistry of the atmosphere and oceans. That's the conclusion of a report by James McWilliams, an applied mathematician and earth scientist at the University of California, Los Angeles. The mathematics of complex models guarantees that they will differ from one another, he argues. Therefore, says McWilliams, climate modelers need to change their approach to making predictions.

Julie Rehmeyer weighs in with an excellent summary of McWilliams' report. Although there are well-known shortcomings in current climate models, a key observation is this:

McWilliams says that discrepancies among models do not undermine the most crucial conclusion of climate modeling—the notion that increased levels of greenhouse gases emitted by people are causing the Earth to warm and will continue to do so. He notes that every credible climate model ever made has pointed to that same conclusion. "All sorts of smart climate scientists have tried to produce a model that doesn't show future warming," he says, "and no one has been able to in a credible way."

Happily, McWilliams' report is open access, and can be found here.

The Truth About Denial

If you think those who have long challenged the mainstream scientific findings about global warming recognize that the game is over, think again. Yes, 19 million people watched the "Live Earth" concerts last month, titans of corporate America are calling for laws mandating greenhouse cuts, "green" magazines fill newsstands, and the film based on Al Gore's best-selling book, "An Inconvenient Truth," won an Oscar. But outside Hollywood, Manhattan and other habitats of the chattering classes, the denial machine is running at full throttle—and continuing to shape both government policy and public opinion.

Sharon Begley at Newsweek gives us a detailed and hard-hitting account of the political tactics and strategies that global warming deniers have used over the years in attempting to discredit climate change science and prevent any effective government response. Mentioned in passsing is a review by Congressman Rush Holt (D-NJ), a PhD physicist, of Al Gore's book and movie, An Inconvenient Truth. It appeared in Science last month, and can be found here (subscription rqd).

Heretical Thoughts about Science and Society

My first heresy says that all the fuss about global warming is grossly exaggerated. Here I am opposing the holy brotherhood of climate model experts and the crowd of deluded citizens who believe the numbers predicted by the computer models. Of course, they say, I have no degree in meteorology and I am therefore not qualified to speak. But I have studied the climate models and I know what they can do.

The author of this piece, Freeman Dyson, is (of course) a highly-respected mathematician and theoretical physicist who has frequently in his long career written very intelligently about scientific and cultural subjects far outside his nominal sphere of expertise. Here he expresses skepticism about computer climate models and their general proclivity to support the idea of anthropogenic global warming.

However, his distinguished status does not mean he is correct on this particular issue, any more than, say, Linus Pauling was correct in his championship of the the health benefits of megadoses of vitamin C. As Pauling himself has been quoted as advising "When an old and distinguished person speaks to you, listen to him carefully and with respect – but do not believe him. Never put your trust in anything but your own intellect. Your elder no matter whether he has gray hair or lost his hair, no matter whether he is a Nobel Laureate, may be wrong."

The Changing Arctic: A Response to Dyson's "Heretical Thoughts"

Knowing that Arctic climate models are imperfect, it would be reassuring for me, if not for the scientists, to be able to write that scientists keep making grim predictions that just that don't come true. If that were so, we could follow Dyson's line that the models aren't so good and "the fuss is exaggerated". Scarily, the truth is the other way around. The ice is melting faster than the grimmest of the scientist's predictions, and the predictions keep getting grimmer. Now we are talking about an Arctic free of ice in summer by 2040.

Author Alun Anderson, who has had top-level positions with Nature, Science, and New Scientist, gives a sensible rebuttal to Dyson's essay.

Science vs. politics gets down and dirty

Malicious, vindictive and mean-spirited. These are words that might surface in divorce court.

But they have been lobbed in the course of a different estrangement: the standoff between the Bush administration and the nation's scientific community.

The relationship, which has been troubled since the dawn of the Bush presidency, hit a new low last month when Richard Carmona, surgeon general from 2002 to 2006, lashed out at his former colleagues in testimony before a House committee.

This one isn't, strictly speaking, about climate change. It's more like the political science of contemporary science policy in the U. S. – but climate change is one of two or three leading scientific issues currently under contention. What this is really about is all-out propaganda warfare being waged by a highly ideological administration on behalf of its supporters (mainly in big business and organized religion) against parts of reality-based science that threaten the economic or ideological interests of those supporters. Political scientists will be studying this conflict for years to come, even if it does not further escalate.

Tags: climate change, climate modeling, global warming, science policy

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The role of hostility, anger, and depression in inflammation

Hasn't it "always" been known that anger and hostility raises one's blood pressure? However that may be, a recent study shows that the connection of hypertension with chronic anger and hostility may involve a disturbed immune system and inflammation – in addition to the well-known blood vessel constriction that is a part of the "fight or flight" stress response.

Hostile Men Could Have Greater Risk For Heart Disease

Men who are hostile and prone to frequent intense feelings of anger and depression could be harming their immune systems and putting themselves at risk for coronary heart disease as well as related disorders like type 2 diabetes and high blood pressure, a new study finds.

The results were found in a 10-year study of U. S. veterans of the Vietnam war.

The men had a series of blood levels taken on three occasions between 1992 and 2002. Researchers measured two immune system proteins known as C3 and C4. Both are markers of inflammation, which is the body’s response to injury or infection. Changes in C3 and C4 are associated with a number of diseases, including some that negatively can affect the arteries around the heart, such as diabetes.

Men whose psychological screening showed the highest level of hostility, depressive symptoms and anger had a 7.1 percent increase in their C3 levels, while men with low levels of these attributes showed no change over the 10-year study period.

Here's another report on this research: Hostility, anger linked to chronic inflammation

But a 2004 study had already demonstrated a stronger correlation between psychological variables and a marker of inflammation (C-reactive protein):

Anger, Hostility And Depressive Symptoms Linked To High C-reactive Protein Levels

Researchers at Duke University Medical Center have discovered that otherwise healthy people who are prone to anger, hostility and mild to moderate depressive symptoms produce higher levels of a substance that promotes cardiovascular disease and stroke.

The substance, C-reactive protein (CRP), has garnered considerable attention for its role in both promoting and predicting cardiovascular disease and stroke in initially healthy people. It is produced by the liver in response to inflammation, and inflammation has recently been shown to underlie the plaque that forms inside arteries as they clog.

The Duke study is the first to link this combination of negative psychological attributes with higher levels of CRP in people without traditional risk factors for heart disease...

More specifically,

121 healthy men and women were asked to complete standard personality questionnaires in which they described their psychological attributes, including anger, hostility and depression. The volunteers did not have any pre-existing conditions -- such as smoking, high blood pressure, diabetes or heart disease -- that would predispose them to having high CRP levels. High-sensitivity blood tests were then conducted to measure CRP levels.

Respondents who were prone to anger, had high hostility levels, and showed mild to moderate symptoms of depression had two to three times higher CRP levels than their calmer counterparts. The more pronounced their negative moods, the higher CRP levels they had, the study showed.

In addition, the researcher had previously shown a relation between the psychological variables and another inflammatory substance (interleukin-6):

[H]ostile people who exhibit symptoms of depression have higher levels of stress hormones and circulating levels of an inflammatory substance called interleukin 6, another marker of inflammation that has been shown to predict heart disease in initially healthy people.

A number of other studies have demonstrated relationships between psychological stress conditions and disease states that involve the immune system, such as this one from 2006:

Anger And Hostility Speed Up Decline In Lung Power

The authors point out that hostility and anger have been associated with cardiovascular disease, death, and asthma, and that previous research has suggested that changes in mood can have short term effects on the lungs.

Anger and hostility will alter neurological and hormonal processes, which in turn may disturb immune system activity, producing chronic inflammation, suggest the authors.

An accompanying editorial comments that the physiological components of anger and stress overlap, and stress is well known to affect the immune system.

Bottom line: Get control over anger and depression if you want to stay healthy.

Of course, this is all closely related to what I discussed just a couple of weeks ago on stress and weight gain and in particular the extensive research of Robert Sapolsky summarized here.

Additional references:

• Coping With Stress Improves Cholesterol
  
• High Hostility May Predict Heart Disease More Than Other Risk Factors Such as Cholesterol and Smoking
  
• Hostility is among best predictors of heart disease in men
  

Tags: inflammation, stress, anger, hostility, depression, cardiovascular disease, hypertension

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Readings, 22 August 2007

It's all physics, astrophysics, and astronomy in this edition. Hope you find something interesting here.

The text following each item is quoted material, except for editorial comments, which are in color.

Dark matter

'Dark matter' doubters not silenced yet

Astro­no­mers have be­lieved for dec­ades that most of the mat­ter in the cos­mos is un­seen. It be­trays it­self only through its gravita­t­ional pull on vis­i­ble ob­jects, whose move­ments are of­ten hard to ex­plain with­out this “dark mat­ter.”

And the past year has seen in­creas­ingly bold claims that as­tro­no­mers have “proved” the stuff’s ex­ist­ence.

De­spite that, there’s a core of doubt­ers who are­n’t go­ing away. Many of them are stick­ing by an al­ter­na­tive the­o­ry that holds that tweak­ing our un­der­stand­ing of gra­vity could ex­plain things bet­ter than in­vok­ing some un­seen sub­stance un­like any we know.

However, the alternative theories have plenty of problems too.

Dark Matter—What's Out There?

For thousands of years, people have gazed at the stars and wondered, "What's out there?" But it wasn't until the 1930s that anyone realized there is much more out there than meets the eye. Recent observations have proven that about 22 percent of the universe is made out of a "dark matter" that is like the wind—although invisible, its influence can be seen. In a recent paper, SLAC Theoretical Physicist Michael Peskin provides an overview of how scientists are trying to unlock the mysteries of dark matter.

Researchers use high-tech machines to detect dark matter

In deep underground laboratories around the globe, a high-tech race is on to spot dark matter, the invisible cosmic glue that's believed to keep galaxies from spinning apart.

Whoever discovers the nature of dark matter would solve one of modern science's greatest mysteries and be a shoo-in for the Nobel Prize. Yet it's more than just a brainy exercise. Deciphering dark matter - along with a better understanding of another mysterious force called dark energy - could help reveal the fate of the universe.

Cosmic 'train wreck' defies dark matter theories

Disturbing evidence has emerged from the wreckage of an intergalactic pile-up suggesting that the already mysterious substance known as dark matter may be even less well understood than astronomers thought.

Additional articles about this research: here, here

Other things

Supercollisions on the horizon?

The project staggers the imagination: a machine that would stretch 20 miles through the bedrock 400 feet beneath Kane, DuPage and perhaps Will Counties. It could help physicists discover mysterious forces of the universe and new dimensions in the fabric of space and time.

But there are other mysteries to resolve before the first spade is turned for a proposed, multibillion-dollar International Linear Collider scientists hope to center under Fermi National Accelerator Laboratory's Batavia campus.

What would the neighbors think about subatomic particles being fired at nearly the speed of light under west suburban homes, back-yard pools and cornfields? And how to accommodate any criticisms in advance and bring folks onboard?

Something to read if you want to know a little about advanced particle accelerators, and a lot about the problems of getting one built.

Fears over factoids

Recent TV programmes have claimed that the Earth could be destroyed by black holes created in particle accelerators and that helium-3 from the Moon could be used for fusion energy. Frank Close warns that these "factoids" must be stamped out before they become accepted as facts

Here's an example of the kind of misinformation that can interfere with projects such as described in the previous item. Sadly, general scientific literacy being what it is, such misinformation spreads too easily.

Catching the Gravitational Wave

At first, Albert Einstein believed that gravitational waves existed, ripples small and large in the curvature of space and time. But he repeatedly changed his mind, first doubting their existence, then believing, and then changing his mind again.

In the end, after decades of debate, scientists confirmed every main point of Einstein's early theory of gravitational waves. In his new book, Traveling at the Speed of Thought: Einstein and the Quest for Gravitational Waves, published by Princeton University Press, University of Arkansas professor Daniel Kennefick traces the history of a theory that researchers believe will help them one day better understand some of the greatest mysteries in the universe.

Testing the elements of the Big Bang

Measurements of the amount of lithium in the universe combined with precision data from the cosmic microwave background are challenging our understanding both of stellar astrophysics and possibly even Big Bang nucleosynthesis itself, as Kenneth Nollett explains.

I wrote a little about this topic two months ago, here. And by the way, Ralph Alpher, who played a leading role in nucleosynthesis theory, died very recently, on August 12 – see next item.

Ralph Alpher, 86; pioneering physicist in cosmic research overlooked for a Nobel Prize

Ralph Alpher, the "forgotten father of the Big Bang" whose calculations provided the theoretical underpinning of the theory but were ignored when it came time to pass out Nobel Prizes, died Sunday at an acute care facility in Austin, Texas.

Other obituaries: here, here, here.

Indium arsenide may provide clues to quantum information processing

“We’re not saying we’ve built a quantum computer,” Andreas Fuhrer tells PhysOrg.com, “but this is an important first step towards spin manipulation via the spin-orbit interaction.”

Fuhrer, a scientist with the Department of Solid State Physics/Nanometer Consortium at Lund University in Sweden, points out that one way quantum information processing might come about is through the manipulation of spin states.

This is one example of how "spintronics" may make it possible to implement a quantum computer.

Scientists' galaxy quest yielding hundreds of new planets

It's boom time for planet hunters. Astronomers are bagging new worlds at an average rate of more than two a month.

As of July 20, the latest available date, 246 extrasolar planets had been detected circling other stars in the Milky Way galaxy. Among them are 25 alien "solar systems" consisting of two, three or four bodies orbiting single suns.

And the hits just keep coming, such as this, and this.

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Update on mirror neurons

I had a piece about mirror neurons here a year and a half ago. It seems to have been popular. There was a shorter piece here.

There's been a bit of recent news on the subject:

Culture Influences Brain Cells: Brain's Mirror Neurons Swayed By Ethnicity And Culture

In their study, the researchers wanted to investigate the imprint of culture on the so-called mirror neuron network. Mirror neurons fire when an individual performs an action, but they also fire when someone watches another individual perform that same action. Neuroscientists believe this "mirroring" is the neural mechanism by which we can read the minds of other people and empathize with them.

When it comes to the influence of culture, they found that indeed, the mirror neuron network responds differently depending on whether we are looking at someone who shares our culture, or someone who doesn't.

A special case of this culture specificity is language, and almost a year ago there was some research reported that linked written language with mirror neurons:

First Evidence Found of Mirror Neurons Role in Language

What do we find so gripping about a good book, the kind that makes us stay up later than we should to find out what happens to hero or heroine?

A new brain imaging study from UCLA may provide an answer, and further, shed light on the language problems common to autistic children. In a study published in the Sept. 19 issue of Current Biology, UCLA researchers show that specialized brain cells known as mirror neurons activate both when we observe the actions of others and when we simply read sentences describing the same action. When we read a book, these specialized cells respond as if we are actually doing what the book character was doing.

Another article on this research: here.

In fact, a similar relation seems to exist between spoken language and mirror neurons:

Strong Mental Link Between Actions And Words

The brain's premotor cortex shows the same activity pattern when subjects observe an action as when they hear words describing the same action, the study's authors said.

Concurrently with those reports, there were others linking mirror neurons with (non-linguistic) auditory stimuli: here, here, here.

Further research appeared this January relating (musical) sounds and mirror neurons:

New Study Shows Brain Rapidly Forms Link Between Sounds And Actions That Produce Them

The researchers taught nine subjects with no previous musical training to play a five-note, 24-second song on a keyboard. Then they ran functional magnetic resonance imaging (fMRI) scans while the subjects listened to the song they had just learned, a different song using the same five notes, and a third song made up of additional notes.

When the subjects listened to the familiar music, their brains showed activity in a network of areas in the frontal and parietal lobes that are involved in the control of movements. The authors note that Broca's area, the human equivalent of the area in the brain where mirror neurons were found in monkeys, was particularly active when subjects listened to music they knew how to play compared with equally familiar music they did not know how to play.

Update: Here's an article on the subject that references this note: How Your Brain Allows You to Walk in Another's Shoes.

Background:

The mind's mirror

What Do Mirror Neurons Mean?

Reflecting on Another's Mind

The Origin of Speech

Tags: mirror neurons, neuroscience

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Readings, 20 August 2007

The text following each item is quoted material, except for editorial comments, which are in color.

Will John Wilbanks Launch the Next Scientific Revolution?

Enter John Wilbanks, executive director of the Science Commons initiative, and the six-year-old innovation of its parent organization, Creative Commons—an intelligent, understandable copyright that's revolutionizing how everything from photos to publications are shared. Wilbanks and his team (which includes Nobel Prize winners Joshua Lederberg and John Sulston) are focused on three areas where roadblocks to scientific discovery are most common: in accessing literature, obtaining materials, and sharing data.

Entrepreneurs See a Web Guided by Common Sense

From the billions of documents that form the World Wide Web and the links that weave them together, computer scientists and a growing collection of start-up companies are finding new ways to mine human intelligence.

Their goal is to add a layer of meaning on top of the existing Web that would make it less of a catalog and more of a guide — and even provide the foundation for systems that can reason in a human fashion. That level of artificial intelligence, with machines doing the thinking instead of simply following commands, has eluded researchers for more than half a century.

This is a December 2006 article by computer-savvy New York Times contributor John Markoff, about the still-evolving "Semantic Web".

The Real Transformers

I was introduced to my first sociable robot on a sunny afternoon in June. The robot, developed by graduate students at the Massachusetts Institute of Technology, was named Mertz. It had camera sensors behind its eyes, which were programmed to detect faces; when it found mine, the robot was supposed to gaze at me directly to initiate a kind of conversation. But Mertz was on the fritz that day, and one of its designers, a dark-haired young woman named Lijin Aryananda, was trying to figure out what was wrong with it. Mertz was getting fidgety, Aryananda was getting frustrated and I was starting to feel as if I were peeking behind the curtain of the Wizard of Oz.

Just in case (excusably) you can't infer what it's about from the title, this longish article is about "sociable robots".

Its Poor Reputation Aside, Our Fat Is Doing Us a Favor

We are now in what feels like the 347th year of the fastidiously vilified “obesity epidemic.” Health officials repeatedly warn that everywhere in the world people are gaining too much weight and putting themselves at risk of diabetes, high blood pressure, heart disease and other obesity-linked illnesses, not to mention taking up more than their fair share of molded plastic subway seat.

It’s easy to fear and despise our body fat and to see it as an unnatural, inert, pointless counterpoint to all things phat and fabulous. Yet fat tissue is not the problem here[.]

Natalie's writing style isn't exactly my cup of tea – too flowery and gaudy for my taste. However, what she writes is interesting, informative, and generally sound.

Bonobos, Left & Right

Imagine that you’re a writer and you have decided to offer your readers a first-hand account of the politically correct primate, the idol of the left, known for its “gay” relations, female supremacy, and pacific life-style. Your focus is the bonobo: a relative of the chimpanzee, and genetically equally close to us as the chimpanzee....

But whatever we find out, a Hobbesian make-over of the bonobo is not to be expected any time soon. I just can’t see this ape go from being a gentle, sexy primate to a nasty, violent one. Japanese primatologist Takeshi Furuichi, perhaps the only scientist to have studied both chimpanzees and bonobos in the forest, said it best: “With bonobos everything is peaceful. When I see bonobos they seem to be enjoying their lives.”

Frans deWaal, the author of this piece, is generally considered the authority on bonobos. But were you aware that green-technology expert Amory Lovins is also interested in these primates? See this and the videos here and here.

Swingers

Bonobos are celebrated as peace-loving, matriarchal, and sexually liberated. Are they?

This is the (rather long) article that Frans deWaal is responding to in the previous item.

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Dead tree publishing

Had a few further thoughts on a subject I return to from time to time...

Apropos of this item I mentioned here on the subject of scientific journals and publishing: It is a general fact that paper-based publishing is expensive, because of high fixed costs and marginal costs of materials (paper), printing, and distribution. Since the fixed costs are only slightly proportional to volume, they are especially a problem for small-circulation publications such as scientific journals.

With a high-volume publication such as a celebrity/gossip magazine the fixed costs are relatively small, and in any case there is plenty of advertising revenue to cover the expenses. Not so for scientific journals, or even most scientifically oriented publications for a general audience. The net result is that writers are under considerable pressure to keep their work brief and concise – minimize page count, column-inches, and word count as much as possible within fixed limits of "available" space. "All the news" – and only the news – that fits is printed.

Consequently, in publications for a general audience, there is a lot of pressure to leave out details and background that is "too technical", in favor of light and fluffy material that readers with a 9th grade reading level can easily absorb. Experienced science writers who advise aspiring writers cringe – literally – when critiquing the work of advisees if it is too lengthly and detailed. (Yes, S. B., I mean you.)

But the other side of the coin is that the writers of papers published in scientific and technical journals are subjected to draconian page count or word count limits, or even must pay (from their grants or institutional budgets) for each page published. And so they are under pressure to leave out all non-technical details, explanations, and background that the professional audience is presumed to know. And consequently, even if some member of the public who is not professional in the specific field of the journal article should happen to gain access to it, such a reader is likely to have difficulty deciphering the necessarily cryptic language of professionals in the field.

Online publication of technical scientific research does, or can, change all that. If the publication is entirely online, the costs of materials, printing, and distribution can be drastically lower. Even if printed publication is continued, online versions can be relieved of most or all space constraints, allowing writers to add to the online version as much explanatory detail and background as they wish. And at the same time, readers benefit from greatly reduced (or eliminated) charges, and the freedom to read only the parts suitable for their level of expertise.

It seems to me that everyone – except maybe the for-profit publishers – stands to benefit from open-access, low-price or free, online publication. Am I missing something?

Comments are welcome.

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Readings, 5 August 2007

I'm trying a new approach to this, so we have a bumper crop of readings this week. Don't count on as much every time, but have fun with the current list.

The text following each item is quoted material, except for editorial comments, which are in color.

General and physical science

Open Access and the Progress of Science

The power to transform research communication may be at each scientist's fingertips.

Open access publishing seems very important to me. It's quite frustrating – for both the writer and the reader – to present an overview of some important scientific research, yet have the actual research publication be inaccessible to most readers, and at best accessible to a few only by jumping through hoops. This is especially frustrating in the case of research that may have personal importance to certain readers, as with health and medical issues. It's also a major barrier to raising the scientific literacy of the public when there is no practical way for the public to gain a better understanding of a subject – by going to the original research papers – than provided by the mass media.

The chemistry of space grows more complex

The chemistry of outer space continues to amaze astronomers. After several decades of doubt, they know that chemical processes around and between stars produce complex molecules including precursors of organic life. But recent discoveries with a new observing technique show they have barely glimpsed what's really going on.

Space station's future in doubt

NASA has only a slim margin of error for completing construction of the international space station before the space shuttle is retired -- and more concerns about supplying it after that date....

And even if no unforeseen scheduling issues arise, experts said NASA faces problems dealing with changes to its work force as the agency moves to a future moon-Mars exploration program. And there is a shortage of science being done on the space station, conceived as a 200-mile-high floating laboratory.

In order to support real scientific research, NASA should be provided with a little of the hundreds of billions of $$ now being squandered on military boondoggles. Failing that, it would be a blessing if funding for real science came from savings that would result if the space station were simply abandoned, or at least mothballed for a few years. For comments regarding better use by NASA of its budget, see this and this.

The Great Global Warming Swindle Swindle

With all those other endangered species going extinct it's nice to know there's still a handful of global warming skeptics kicking around. ABC Science Online's Bernie Hobbs looks at the facts behind the vitriol in the film that's got everyone looking up the word 'polemic'.

Nice exposé of a propaganda film put out by global warming skeptics.

Self Assembly

Hofstadter's new book, deeply thought-provoking though it is, is less engaging than either Gödel, Escher, Bach or Le Ton Beau de Marot. Yet I Am a Strange Loop carries the high hopes of its author, not just those of its readers. Hofstadter feels that his first book, despite its massive popularity, has been widely misunderstood. Its fundamental message seems not to have been noticed: "It sometimes feels as if I had shouted a deeply cherished message out into an empty chasm and nobody heard me." This new volume is his attempt to set the record straight.

The core intellectual claim, then, is much the same as that of Gödel, Escher, Bach: namely, that a proper understanding of Gödel's proof helps us to see that life, mind and self are all constituted not by biochemistry but by the higher-level patterns that biochemistry makes possible. In particular, human selves are abstract self-referential (reflexively looping) patterns that arise spontaneously out of the meaningless base of neural activity.

Margaret Boden's review of Douglas Hofstadter's new book is brief, but should not be missed.

Do Loops Explain Consciousness? Review of I Am a Strange Loop

Another review of Hofstadter's book, by no less than Martin Gardner, who opines on its place in the philosophy of consciousness.

Mathematics

Poincaré, Perelman and proof

This is a review of Donal O'Shea's The Poincaré Conjecture: In Search of the Shape of the Universe. Both author and reviewer (Nigel Hitchin) are professional mathematicians, so the indications are this book is a must-have if you're even vaguely interested in the subject. The review itself nicely summarizes both the technical issues and the personal story of Grigori Perelman, who proved the Poincaré conjecture.

GEOMETRY AND THE IMAGINATION: Pricey Proof Keeps Gaining Support

No report on advances in topology is complete these days without an update on Russian mathematician Grigory Perelman's proof of Thurston's Geometrization Conjecture and its million-dollar corollary, the Poincaré conjecture (Science, 22 December 2006, p. 1848). After poring over Perelman's papers for 4 years, topologists are confident of the result, says John Morgan of Columbia University, who gave an overview of the proof at the Thurston conference.

There were other interesting results presented at the conference in honor of William Thurston. You can access accounts of these results here (subscription required for full access).

Tom Lehrer's Derivative Ditties

Should you be not old enough for the name Tom Lehrer even to ring a bell for you, Ivars Peterson offers a summary of the mathematician-songwriter's work having special appeal to the mathematically inclined. Such as "New Math". Somehow, he neglects to mention "Lobachevsky". Or perhaps you'd just like to know of a catchy little tune that's a hilarious send-up of Catholicism: "The Vatican Rag". (Needs to be heard sung to be really appreciated.) And for chemistry devotees there's "The Elements".

Technology

Building an Immersive Web

Early virtual worlds such as ­Second Life demonstrate that highly visual, 3-D online environments hold the potential to transform the way humans interact not only with computers but with each other .... Hyped as they are, these immersive environments address two fundamental aspects of being human: our visual and social natures.

A Smarter Web

New technologies will make online search more intelligent--and may even lead to a "Web 3.0."

This longish article may be for you if you have ever puzzled over questions like "What comes after Web 2.0?" or "What the heck is this 'Semantic Web' thing?"

At last, semiconductor industry begins embracing nano

Even though the conservative semiconductor industry, with its extreme performance and manufacturing demands, has done much of its manufacturing in nanoscale dimensions for years, it hasn’t yet had much use for the unique properties of nanoparticles, fullerenes, nanowires, quantum dots, etc.-the technologies usually considered “true” nanotech. Nor have the nanoscale patterning processes developed by the chip makers been of much use to the rest of the nanotechnology world.

But the old ways are starting to change.

A bot's life

Robotic designs based upon natural organisms are as diverse as the animal world itself. There are devices in the works that mimic caterpillars, spiders, dogs and octopuses. Their goals and purposes are equally varied, from new medical treatments to space labor to being a soldier's best friend.

Life sciences

What Do Mirror Neurons Mean?

The discovery of mirror neurons in the frontal lobes of macaques and their implications for human brain evolution is one of the most important findings of neuroscience in the last decade. Mirror neurons are active when the monkeys perform certain tasks, but they also fire when the monkeys watch someone else perform the same specific task. There is evidence that a similar observation/action matching system exists in humans.

This is a symposium comprising several papers on mirror neurons published in the last three years. I wrote about the subject here and here. These papers are technical but worth a look.

Genetic Engineers Who Don’t Just Tinker

FORGET genetic engineering. The new idea is synthetic biology, an effort by engineers to rewire the genetic circuitry of living organisms.

The ambitious undertaking includes genetic engineering, the now routine insertion of one or two genes into a bacterium or crop plant. But synthetic biologists aim to rearrange genes on a much wider scale, that of a genome, or an organism’s entire genetic code. Their plans include microbes modified to generate cheap petroleum out of plant waste, and, further down the line, designing whole organisms from scratch.

Can Adult Stem Cells Do It All?

Scientists may have turned mouse skin cells into embryolike stem cells, but prior claims for the power of adult cells have yet to stand the test of time.

Don't believe everything you read by opponents of embryonic stem cell research, such as the supposed power of adult stem cells to do whatever ESCs can.

An Elegant Molecular Dance

Her team's strategy is to spy on biological machines in action, watching as individual molecules fold, interact with one another, and do their work. They use sensitive optical imaging techniques to collect extraordinarily detailed pictures of this activity—watching, for example, as a single molecule of RNA folds into its functional shape or a tiny polio virus invades a mammalian cell. Combining those images with findings from their experiments in molecular biology and biochemistry, the scientists are revealing how the structural dynamics and movements of molecules drive biological processes. ...

One of the lab's most recent successes, however, is developing a precise portrait of the molecular dance that creates telomerase, a complex of molecules that protects the ends of chromosomes during DNA replication. Michael Stone, a postdoctoral fellow in Zhuang's lab, led the study published in the March 22 issue of Nature. The enzyme is essential for rapidly dividing cells, such as those in a developing embryo, but is usually shut off in healthy adult human cells. Upregulating the enzyme's activity allows adult cells to achieve a dangerous immortality. The enzyme is inappropriately active in the vast majority of human cancers, making it a potential target for new cancer therapies. ...

With experiments like these, Zhuang says biophysicists and biologists are steadily moving their field toward the kind of fundamental and quantitative ways of explaining the world that first attracted her to science.

Arresting developments

Dr Harel has been working on a computer model of C. elegans. He hopes this will reveal exactly how pluripotent stem cells—those capable of becoming any sort of mature cell—decide which speciality they will take on. He thinks that a true understanding of the processes involved will be demonstrated only when it is possible to build a simulation that does exactly—but artificially—what happens in nature.

There are interesting ideas in this short piece, the nature of which you would never guess from the dreadfully useless title. For example, the idea of computer modeling of entire, albeit simple, organisms. Inevitably, with the ever-increasing power of supercomputers, it will be possible before long to model more complex animals, like, say, jellyfish. This will enable zoologists who study such critters to gauge the quality of their understanding by observing how lifelike their computer models are.

Brain Boosters

Two days from now I'm planning to further tweak my mind by taking a brain-boost pill. Called Provigil, it differs from its predecessors in that it is believed to home in on a section of the brain that helps govern alertness and memory. The pill is manufactured by ­Cephalon of Frazer, PA, and its active ingredient is called modafinil. The drug's targeted delivery is supposed to prevent the side effects of stimulants that diffuse throughout the brain and rev up everything.

In addition to the Provigil the writer discusses electrical stimulation devices for the brain, which supposedly enhance performance, however slightly. Personally, I find caffeine works pretty well, and abundant evidence that's pretty well-known to all suggests I'm hardly alone. But did you know that the caffeine, plus exercise, may lower risk of skin cancer too?

Health and medicine

Gene therapy trial on hold

As the US Food and Drug Administration prepares to investigate the death of a patient in a phase I/II gene therapy trial for inflammatory arthritis, researchers in the field say the treatment's delivery vector, an adeno-associated virus (AAV), was unlikely to be the culprit.

It will be very good news if these researchers are correct, as a number of mainstream media accounts are portraying this gene therapy trial problem as yet another black eye for the whole concept of gene therapy.

Obesity: A Link to Rare Gene Variations

Sometimes, the rarest of the rare can still have an impact. A multi-institutional team of scientists led by Berkeley Lab geneticist Len Pennacchio has found that extremely uncommon gene variations likely contribute to obesity.

How and why — and to what extent — remain a mystery, but the research adds another clue to the problem of obesity, which is reaching epidemic proportions in developed nations. Overeating and lack of exercise loom as the chief culprits. But heredity and gene defects are implicated too, and now scientists have a better understanding of their role.

AIDS Abated: Genome scans illuminate immune control of HIV

Some people who contract HIV, the virus that causes AIDS, maintain low amounts of the virus in their bodies for years. These long-term nonprogressors—so called because a decade or more can pass before they develop full-blown AIDS—have attracted great attention from researchers.

Now, using powerful, whole-genome scans, researchers have identified three genetic variations that partially explain why some HIV-infected people develop AIDS quickly while others keep it at bay.

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