28 September 2007

Hexayurts and Other Cheap, Rapid Shelter

The Hexayurt is a clever idea for a quick, cheap, lightweight shelter. It can be seen as a part of an overall disaster relief program. Or it can be seen as a fun project, like these cardboard geodesic domes.

Other similar quick shelter ideas include the $500 all-season house and the Grancrete House. These quick houses have the potential to stand up to some fairly strong storms better than most fabric structures. In case of earthquake, they would do little damage to their inhabitants, unlike brick and earthen houses. Of course, if you want a house that is likely to survive most any disaster, build a monolithic dome.

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27 September 2007

Transcranial Magnetic Stimulation--For Targeted Neural Suppression

Transcranial Magnetic Stimulation (TMS) is a noninvasive way to stimulate neural activity using noninvasive electromagnetic coil devices placed over specific areas of the scalp. TMS has been used to treat depression, schizophrenia, and to rehabilitate from stroke (CVA).

Recent research suggests that TMS might also be used to selectively suppress specific regions of the brain, for research and possibly for therapy.
In a set of experiments, the researchers used TMS to generate weak, electrical currents in the brain with quick 2- to 4-second bursts of magnetic pulses to the visual cortex of cats. Direct measurements of the electrical discharge of nerve cells in the region in response to the pulses revealed that TMS predictably caused an initial flurry of neural activity, significantly increasing cell firing rates. This increased activity lasted 30 to 60 seconds, followed by a relatively lengthy 5 to 10 minutes of decreased activity.

What the researchers were able to determine for the first time was that the neural response to TMS correlated directly to changes in blood flow to the region. Using oxygen sensors and optical imaging, the researchers found that an initial increase in blood flow was followed by a longer period of decreased activity after the magnetic pulses were applied.

"This long-lasting suppression of activity was surprising," said Brian Pasley, a graduate student at HWNI and co-lead author of the study. "We're still trying to understand the physiological mechanisms underlying this effect, but it has implications for how TMS could be used in clinical applications."

The critical confirmation of the connection between blood flow and neural activity means that researchers can use TMS to alter neural activity, and then use fMRI, which tracks blood flow changes, to assess how the nerve cells respond over time.

"One of the most exciting applications of TMS is the ability to non-invasively modify neural activity in specific ways," said Pasley. "The brain is malleable, so brain stimulation may be used to alter and promote specific functions, like learning and memory, or suppress abnormal activity that underlies neurological disorders. If we can figure out the right ways to stimulate the brain, TMS will likely be useful in attempts to improve neural function."

Initially, this use of TMS will probably be used by researchers with animals, to test its potency and safety. But neurologists are desperately looking for good tools to rehabilitate stroke patients and patients with neurodegenerative disorders.

The combination of TMS with neurofeedback should be a particularly potent tool for neurologists and psychiatrists who are just a bit bolder than most of their colleagues.


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26 September 2007

SENS Update

SENS3, the third biannual SENS conference was held 6-10 Sept 2007 at Queens College, Cambridge. An excellent summary of the conference is available at Ouroborus. Apparently, progress has been made by several researchers on multiple fronts. To access talks from previous conferences, go to SENS1 here, or SENS2 here.

Aubrey de Grey's SENS is a seven-part approach to engineering increased longevity in humans. SENS research is being funded by the Methuselah Foundation, and other funding agencies and individuals.

Other important recent conferences of note were the Singularity Summit in San Francisco and the Nano-Bio technology Conference in Tucson. Both of those conferences were well covered by Michael Anissimov.

Hat tip Brian Wang

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25 September 2007

The Real Wars--How Most North Americans Die

While approximately 1,000 US military service members have died every year for the past three years while away at war, the true slaughter of US citizens takes place on America's highways, in homes, hospitals, and workplaces.
  1. Heart disease: 654,092
  2. Cancer: 550,270
  3. Stroke (cerebrovascular diseases): 150,147
  4. Chronic lower respiratory diseases: 123,884
  5. Accidents (unintentional injuries): 108,694
  6. Diabetes: 72,815
  7. Alzheimer's disease: 65,829
  8. Influenza/Pneumonia: 61,472
  9. Nephritis, nephrotic syndrome, and nephrosis: 42,762
  10. Septicemia: 33,464

Source: Deaths: Preliminary Data for 2004, tables 7

The image at the top of this post is of Randy Pausch and his children. Randy is an accomplished professor of Computer Science at Carnegie Mellon, diagnosed and under treatment for pancreatic cancer--a particularly rapid and deadly malignancy. It helps to put a face to the statistics.

The real mass casualty wars of our time are these wars taking place on home soil. The true anti-war protesters are those who work against the wanton death and destruction caused by these mass killers.

Speaking only for myself, I would choose a quick death in combat over a lingering death from heart disease, cancer, Alzheimer's, liver disease, Parkinson's, nephrosis, and any number of diseases that kill large numbers of us every year. My long experience in several intensive care units taught me the mercy of a rapid death.

Link to Randy Pausch courtesy of Pastorius via email.

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Saudi Religious Gestapo Get Pepper Sprayed

The Saudi religious police are guilty of beating people to death, fatally trapping schoolgirls in burning buildings, and generally making an oppressive nuisance of themselves across the Kingdom of Saudi Arabia. Is it possible that young Saudis are preparing to overthrow these corrupt medieval religious tyrants of the street?
According to Dr. Al-Marshood, the two commission members approached the girls in order to "politely" advice and guide them regarding their inappropriate clothing.

It gets better:

Consequently, the two girls started verbally abusing the commission members, which then lead to one of the girls pepper-spraying them in the face as the other girl filmed the incident on her mobile phone, while continuing to hurl insults at them.

YouTube, please.

The Eastern Province's head of the commission also revealed that with the help of the police his two employees were able to control the situation.

The two females were then escorted to the police station where they apologized for the attack, were cautioned and then released.

Naturally, I too would like to see the YouTube clip of this promising confrontation. No doubt the Saudi authorities consider it an example of their spoiled youth acting out against proper authority. Perhaps they're unaware of what happened across Eastern Europe in the late 1980s and early 1990s?

Islam is badly in need of reform--beginning in Iran and Saudi Arabia. The religious Gestapo of KSA is exactly the proper target for reform-minded Saudis. Keep it up.

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23 September 2007

The Fallibility of Research Findings--Another Reminder

Following closely on publication of this caution, this NYTimes Magazine piece provides further reasons for careful scrutiny of research findings.

Most people do not have the training in epidemiology and statistics required to judge a research paper's findings. That seems particularly true of many post-modernist minded journalist and academicians. The public should beware of the uncritical acceptance of research findings in the media and on campuses. Recent epidemiological overreach when looking at civilian casualties in Iraq highlights the ludicrous extent to which instruments of data analyses can be prostituted to the service of political journalism.

But the rare political whoring of epidemiology is just the tip of the iceberg. Given the inherent ambiguity of most research data, it is necessary to introduce some disciplined parsimony in transforming data to actionable information. Most scientists (outside of climate modeling) are able to admit the limitations of their findings and methods. Sadly, most "science" journalists too often lack the subtlety and nuance that reporting on science requires. They too easily succumb to the temptation for the "breakthrough", the "blockbuster headline", the sensational patina over what is likely to be "ho-hum" data in reality.

This is not nearly so much a problem for scientists as it is for the public. But if you read the article, you will see that it is also a problem for science.


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Competence: The Road Less Traveled

We at Al Fin blog emphasize the importance of teaching practical competence to children and youth. But adults, too, can acquire competence--if they are disciplined enough.
“The American Dream today is to own your own home,” he said. “It used to be to build your own home.”

He had no practical experience with carpentry, plumbing or electrical work. When he went to the store for supplies, he had to describe what he needed because he’d never learned various fixtures’ proper names.

...But Wernick refused to be swayed. In college, he’d studied math, chemistry and physics and learned theories he was sure he could apply to building. His work followed the pattern of most of history’s great scientists: trial and error.

Eventually, he succeeded. He finished the house and passed inspection. It was invaluable experience for his next dream: building a country home in Northwest Montana.

...In 1980, they decided to take a break from education and focus on building a home in the woods.

They wanted much more than a cabin on their North Fork property. They wanted a real home, a place they could raise their daughter, Rachelle.

They wanted to live off the grid and be completely self-sufficient. The North Fork — with no electricity or other utilities — was just the place.

“It was our dream to have a sustainable country home,” Wernick said.

And so they built their off-the-grid home in western Montana. Then promptly got roped into starting a boarding school on their new homesite.Jerry Wernick demonstrated his personal competence when he buckled down and learned the trade of homebuilding well enough to satisfy fastidious Southern California inspectors. He and his family further demonstrated competence when they successfully built their sustainable off-grid home in Montana.

Having demonstrated their competence twice over, it should be clear that the Wernicks are qualified to teach their boarding students something about competence, at their sustainable home in the Monatana forest. But that was 25 years ago. They have probably learned a great deal since then.

It wasn’t long before other parents heard about the couple tutoring children up the North Fork. Soon the Wernicks had four pupils. By 1982, they realized they had a full-blown school and formally opened Tamarack Springs Academy.

Within a few years, the school was full, and it has remained full ever since. The Wernicks accept just 10 students each year — a small enough number to board the students on their property.

Children have come from all over the country to study at Tamarack Springs.

Most heard about the school from former students or people who’ve met the Wernicks. Horn, from Midland, Mich., first heard about the school from her pastor, Jerry Wernick’s brother-in-law.

Elise Taylor of Calhoun, Ga., is the third member of her family to attend Tamarack Springs. Her older sister, Shannon, attended the school two years ago. Her brother, Michael, is a senior there this year.

For years, Taylor listened to stories about the small school in the woods and its legendary fall and winter campouts. When she was old enough to attend high school, she knew exactly where she wanted to go.

Small pockets of competence flower and grow, sometimes from unlikely seed. While there are few Richard Proennekes in the modern western world, if more persons can learn how to nourish the potential of children and youth in their formative years, sufficient personal competence for meeting the coming challenges might spring up, as if from the void.

Is it really important for adults and youth to learn these basic living skills? Haven't we all grown beyond these primitive ways of thriving? Will it not be a few more years before breakthroughs in biotechnology, nanotechnology, and machine intelligence makes all of this "nonsense" obsolete?

Perhaps, although I seriously doubt it. The forces of Luddist reactionism and religious fanaticism are quite strong in the modern world. While western civilisation has acquired a large amount of momentum, it currently rests upon an electronic economic system that is quite vulnerable to disruption. Since modern research labs depend upon a small number of private and government beneficiaries, disrupting the flow of funds to research would not be terribly difficult for a determined and well-funded foe. Particularly in conjunction with other attacks against physical facilities, energy supplies, information infrastructure, etc.

Even under the best circumstances and economies, the technical problems needed to begin to achieve the goals of SENS regenerative medical engineering, ubiquitous molecular manufacturing, better-than-human machine intelligence, and large scale colonisation of space, will take several decades. If political incompetence (appeasement to primitivism) makes the tasks more difficult, it may take centuries.


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Robots--They Have A Long Way to Go

The above video describes the walking action of "Strider", a three-legged robot of unique design. High scores for innovation.

This wall-climbing robot may suggest more practical, scaled-down designs.

"Scarab" is a lunar prospector robot, with some unique characteristics making it a better prospector.

This article suggests that Japanese old-timers are not interested in interaction with the clutzy kludgy robots that researchers have been sending them. Is it possible that many robotics researchers lack the real-world life perspective necessary to avoid patronizing the old folks. Probably.

If one were to watch IRobot, then take a look at the state of the art in robotics research, it would be obvious that a robot gap exists between the movies and the real world.

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20 September 2007

Can You Carry a 300 Pound Backpack?

This exoskeleton from MIT promises to quadruple a person's carrying capacity at the cost of roughly 1 watt! While the human gait-matching mechanics need further work, the prospect of increasing the weight-bearing capacity of an able-bodied worker into the 200-300 pound range must be tempting for many employers--including many militaries.
In the September issue of the International Journal of Humanoid Robotics, the researchers report that their prototype can successfully take on 80 percent of an 80-pound load carried on a person's back, but there's one catch: The current model impedes the natural walking gait of the person wearing it.

...Exoskeleton devices could boost the weight that a person can carry, lessen the likelihood of leg or back injury and reduce the perceived level of difficulty of carrying a heavy load.

The person wearing the exoskeleton places his or her feet in boots attached to a series of tubes that run up the leg to the backpack, transferring the weight of the backpack to the ground. Springs at the ankle and hip and a damping device at the knee allow the device to approximate the walking motion of a human leg, with a very small external power input (one watt).

Other research teams have produced exoskeleton devices that can successfully carry a load but require a large power source (about 3,000 watts, supplied by a gasoline engine).

1 watt of energy can be supplied by rechargeable batteries. If the worker/soldier is wearing photovoltaic clothing, the exoskeleton can be powere in the daylight without depleting a battery charge, while charging backup batteries at the same time.

This form of human augmentation is evolutionary, rather than revolutionary. Consider it just another slow step in the long march toward cyborgs and augmented humans.

Hat tip Kurzweilai


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Measure of a Man--How Much Can You Take?

Remember the gom jabbar from Dune? The box of pain and fear that only "true humans" can withstand? Here is a real life gom jabbar that may be more than you can stand.
A square transmitter as big as a plasma TV screen is mounted on the back of a Jeep.

When turned on, it emits an invisible, focused beam of radiation - similar to the microwaves in a domestic cooker - that are tuned to a precise frequency to stimulate human nerve endings.

It can throw a wave of agony nearly half a mile.

Because the beam penetrates skin only to a depth of 1/64th of an inch, it cannot, says Raytheon, cause visible, permanent injury.

But anyone in the beam's path will feel, over their entire body, the agonising sensation I've just felt on my fingertip. The prospect doesn't bear thinking about.

"I have been in front of the full-sized system and, believe me, you just run. You don't have time to think about it - you just run," says George Svitak, a Raytheon executive.

...In tests, even the most hardened Marines flee after a few seconds of exposure. It just isn't possible to tough it out.

This machine has the ability to inflict limitless, unbearable pain.
...Silent Guardian and the Taser are just the first in a new wave of "non-lethal" weaponry being developed, mostly in the U.S.

Imagine such a device that was powerful enough to broadcast a pain signal from a satellite in low earth orbit. Would it be used for "ethnic cleansing?" Border control? Or just a new way to conduct old-fashioned warfare? Yes, I know the device is a natural instrument of torture as it is. Humans do bad things to each other. Have you ever read the story of Magellan's voyage to the Spice Islands . . . ?

Hat tip Blogging the Singularity


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Re-Growing Damaged Brain

If humans are to live longer lives, we need ways to regenerate our brains from all sorts of neuronal damage. Adult brains can produce new neurons to replace some forms of brain damage. Maintaining brain function in extreme life extension is a matter of finding ways to expand this inherent ability of the brain.

Hat tip IConrad


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Academic Lobotomy and the Suppression of Ideas

Academic intolerance refuses to hear other points of view. What is worse, academic intolerance refuses to allow anyone else within its power to hear other points of view.
Former President of Harvard Lawrence H. Summers was set to speak in California this week at a dinner meeting of the Regents of the University of California (UC). That is, until his invitation was abruptly cancelled.

Over 150 professors in the UC system, led by Maureen Stanton, a professor in the Department of Evolution and Ecology at UC-Davis, started an online petition drive to put the kibosh on Summers’ impending speech. Their preposterous claim was that “inviting a keynote speaker who has come to symbolize gender and racial prejudice in academia conveys the wrong message to the university community and to the people of California.”

Instead, the UC’s regents have sent an altogether different message—the University of California has ceased to value academic freedom.

More generally, the quashing of Summers’ speech points to a troubling trend in academia. Increasingly, the unrestricted marketplace of ideas that must form the heart of any university worth the name is being poisoned by a perverse pressure to conform truth to political agenda and stifle any speaker who espouses uncomfortable or invonveneint opinions. In the present case, the culprits are academics who fashion themselves as progressives eager for social justice and tolerance, but the other side of the political spectrum is no less guilty in others. This situation is alarming and dangerous. If academic freedom cannot exist in the university, our society is in trouble.

...Maureen Stanton and company represent the worst of academia. The side that politicizes its classrooms and refuses to hear, or let others hear ideas that they find distasteful or uncomfortable, no matter their merit.

When tenured faculty seize the platform of ideas, and refuse to allow a diversity of ideas to be presented to the university environment--including the regents--it is clear that a tyranny has sprouted on the very ground where tyranny does the most harm to the minds of new generations of youth. The university exists to provide a rich garden of ideas from which young minds may sample and choose. Without that richness of intellectual choice, the youthful mind becomes academically lobotomised.

Maureen Stanton and her ilk reveal an insecurity within themselves which bodes ill for the future of North American academics.


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19 September 2007

Big Babies--Psychological Neoteny Grows More Common, Just As Al Fin Has Predicted

Psychological Neoteny is the retention of immature characteristics of behaviour--shirking from responsibility and seeking to escape the real world--in adults. It has nothing to do with adolescents, nor with the well-documented delayed neurological maturation of various brain centers until the late teens and early to middle twenties. It is an adult phenomenon, and here are some statistics documenting its growth?
it’s actually middle-aged adults — the parents — whose behavior has worsened.

Our most reliable measures show Americans ages 35 to 54 are suffering ballooning crises:

18,249 deaths from overdoses of illicit drugs in 2004, up 550 percent per capita since 1975, according to data from the National Center for Health Statistics.

46,925 fatal accidents and suicides in 2004, leaving today’s middle-agers 30 percent more at risk for such deaths than people aged 15 to 19, according to the national center.

More than four million arrests in 2005, including one million for violent crimes, 500,000 for drugs and 650,000 for drinking-related offenses, according to the F.B.I. All told, this represented a 200 percent leap per capita in major index felonies since 1975.

630,000 middle-agers in prison in 2005, up 600 percent since 1977, according to the Bureau of Justice Statistics.

21 million binge drinkers (those downing five or more drinks on one occasion in the previous month), double the number among teenagers and college students combined, according to the government’s National Household Survey on Drug Use and Health.

370,000 people treated in hospital emergency rooms for abusing illegal drugs in 2005, with overdose rates for heroin, cocaine, pharmaceuticals and drugs mixed with alcohol far higher than among teenagers.

More than half of all new H.I.V./AIDS diagnoses in 2005 were given to middle-aged Americans, up from less than one-third a decade ago, according to the Centers for Disease Control.

What is interesting about this article is not the extreme obtuseness demonstrated by the NY TImes writers [ed: the oped article is written by Mike Males, sociologist and author of a 1996 book defending a previous generation of teens from the accusation that they are stupid, crazy, reckless . . . which are charges that we at Al Fin do not repeat] in their commentary. It is that although the statistics are presented in a typically deceptive manner, it is still possible to see that more adults are behaving badly--precisely as Al Fin's theory of psychological neoteny suggests they will do.

The brains of teenagers are not fully developed. It is quite a good thing, too, because what that means is that the teenager can learn more things more quickly than the adult whose brain is more "set." Of course, teens also lack experience and judgment which might help them make better decisions. Forget about all that.

What is being stated by both Al Fin and the NY Times article, is that large numbers of adults are passing the age of brain maturation without actually learning responsible or wise behaviour. And unlike the adolescent, who has a chance to remake his own brain, and learn wisdom, the psychologically neotenous adult has used up the larger part of his chances to mature.

No, all is not lost. The adult brain still has the ability to generate new neurons, glial cells, etc. With discipline and practise, the adult brain can grow new pathways, learn, myelinate, and mature even more. But the difference in potential to achieve further maturity between most teens and the adult psychological neotenate, is an order of magnitude. The teen has all the advantage.

The lesson to be learned from all this, is that child-rearing and educational methods need to be changed promptly--before more generations of psychological neotenates are thrown out into the world unprepared. The world does not need more criminals, drug addicts, adult escapists from reality and responsibility. If Al Fin must repeat himself to get the point across to persons who are sometimes slow to learn, that is what he must do.


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More on the 88 Monkeys of Duke

What did the infamous 88 Duke University faculty accusers say, when Mike Nifong's case against the athletes began to collapse? "I'm sorry I jumped to conclusions without evidence?" Hardly.
--History professor Peter Wood claimed, in an interview with the New Yorker, that a lacrosse player advocated genocide against Native Americans. His evidence: an anonymous student evaluation in a class of 65.

--Literature professor Grant Farred published an October 2006 op-ed accusing Duke students of “secret racism” for seeking to vote Nifong out of office; in April 2007, he publicly deemed unnamed lacrosse players guilty of “perjury.”

--Houston Baker, by this point having been hired away by Vanderbilt, suggested that the lacrosse players might have been guilty of other rapes (he supplied no evidence) and e-mailed one player’s mother that her son and his teammates were “farm animals.”

Such statements seemed to violate the spirit if not the letter of Duke’s Faculty Handbook, which contains the following passage: “Members of the faculty expect Duke students to meet high standards of performance and behavior. It is only appropriate, therefore, that the faculty adheres to comparably high standards in dealing with students . . . Students are fellow members of the university community, deserving of respect and consideration in their dealings with the faculty.”

Yet — as our book makes clear — the Brodhead administration had shown no willingness to enforce the Handbook’s provisions at any point in the lacrosse affair. In spring 2006, at least three History professors used class time (in classes with lacrosse players) to deliver guilt-presuming lectures, including one who offered what he termed the findings of his “research” — that an “ejaculation had occurred.” An anthropology professor dismissed her class so the students could go outside and watch an anti-lacrosse rally. And a political science professor — after sending an e-mail in which she described the two lacrosse players in her class as accomplices to rape — gave both students an F on the final paper. One sued Duke; in an out-of-court settlement, Duke publicly announced that the grade had been changed (to a “pass”) and paid an undisclosed sum.

Group members disinclined toward unsubstantiated attacks or unprofessional behavior engaged in an Orwellian attempt to redefine the past. Perhaps the best example came in a January 2007 op-ed from English professor Cathy Davidson, who rationalized the Group of 88’s statement as nothing more than saying “that we faculty were listening to the anguish of students who felt demeaned by racist and sexist remarks swirling around in the media and on the campus quad in the aftermath of what happened on March 13 in the lacrosse house. The insults, at that time, were rampant. It was as if defending David Evans, Collin Finnerty and Reade Seligmann necessitated reverting to pernicious stereotypes about African-Americans, especially poor black women.”

These claims were absurd: in late March and early April 2006 virtually no one was publicly defending the lacrosse players “on the campus quad” or anyplace else, much less using racial stereotypes to do so.

While the Group members’ positions might have been divorced from reality, they had a chilling effect on campus discourse. For nearly six months, as an extraordinarily high-profile case of prosecutorial misconduct involving their own students unfolded before their very eyes, not one member of the Duke arts and sciences faculty publicly criticized Nifong’s behavior. The first who did so, Chemistry professor Steven Baldwin, also blasted the Group of 88 for betraying their responsibilities as professors. The response? The next day, the director of Duke’s women’s studies program accused Baldwin of using the “language of lynching,” while the co-director of Duke’s Center for Study of Race, Ethnicity, and Gender sent Baldwin an e-mail implying that they should settle their differences through violence.
Volokh Conspiracy

But the unprofessional behaviour of Duke U's faculty is par for the course for the humanities, on North American university campuses. These tenured clowns rule over their universities like monkey kings, preventing students from being exposed to a diversity of ideas--the only kind of diversity that truly counts in an educational setting such as an university.

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18 September 2007

Phase Change Memory Using Nanowires

The quest to create fast, non-volatile phase-change memory dates to Stanford Ovshinky's 1966 patent application. Since then, many companies such as Intel, have made significant progress toward developing such a potentially revolutionary memory technology. The latest advance comes from a UPenn team that used nanowires to fabricate a phase change memory.
Ritesh Agarwal, an assistant professor in the Department of Materials Science and Engineering, and colleagues developed a self-assembling nanowire of germanium antimony telluride, a phase-changing material that switches between amorphous and crystalline structures, the key to read/write computer memory. Fabrication of the nanoscale devices, roughly 100 atoms in diameter, was performed without conventional lithography, the blunt, top-down manufacturing process that employs strong chemicals and often produces unusable materials with space, size and efficiency limitations.

Instead, researchers used self-assembly, a process by which chemical reactants crystallize at lower temperatures mediated by nanoscale metal catalysts to spontaneously form nanowires that were 30-50 nanometers in diameter and 10 micrometers in length, and then they fabricated memory devices on silicon substrates.

“We measured the resulting nanowires for write-current amplitude, switching speed between amorphous and crystalline phases, long-term durability and data retention time,” Agarwal said.

Tests showed extremely low power consumption for data encoding (0.7mW per bit). They also indicated the data writing, erasing and retrieval (50 nanoseconds) to be 1,000 times faster than conventional Flash memory and indicated the device would not lose data even after approximately 100,000 years of use, all with the potential to realize terabit-level nonvolatile memory device density.

“This new form of memory has the potential to revolutionize the way we share information, transfer data and even download entertainment as consumers,” Agarwal said. “This represents a potential sea-change in the way we access and store data.”

The history of computer memory research is littered with failed concepts that offered great promise, but could not deliver for technical or economic reasons. Phase change memory technology is a relatively simple concept and should not be expensive, once developed. It will be much faster and more radiation resistant than flash memory, and will last much longer. Memory density should also be better than flash, and since it is non-volatile, it may become a replacement for hard disk drives. If it can be made fast enough, it may also replace volatile RAM memory.

In other words, regardless of whether phase change memory is implemented from the top down (lithography) or the bottom up (nano-wires), the underlying technology is likely to come standard, at least in top of the line machines, in the near future.

Hat tip Brian Wang.

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16 September 2007

Learn to Reserve Judgment Until the Facts are All In

A lot of people trust research findings implicitly. Experienced researchers and data analysts do not.
There is increasing concern that most current published research findings are false. The probability that a research claim is true may depend on study power and bias, the number of other studies on the same question, and, importantly, the ratio of true to no relationships among the relationships probed in each scientific field. In this framework, a research finding is less likely to be true when the studies conducted in a field are smaller; when effect sizes are smaller; when there is a greater number and lesser preselection of tested relationships; where there is greater flexibility in designs, definitions, outcomes, and analytical modes; when there is greater financial and other interest and prejudice; and when more teams are involved in a scientific field in chase of statistical significance. Simulations show that for most study designs and settings, it is more likely for a research claim to be false than true. Moreover, for many current scientific fields, claimed research findings may often be simply accurate measures of the prevailing bias. In this essay, I discuss the implications of these problems for the conduct and interpretation of research.
Why Most Published Research Findings Are False

Of course, since this finding is based upon a simulation--and we know from climate science how simulations and computer models are subject to biasing by bad data--we should be suspicious of this finding as well. And rightly so. There is no such thing as perfect data. Some algorithms used in models and simulations are sufficiently recursive so as to create absurd results that diverge wildly with each run.

So, if you are tempted to place too much faith in an area of science that is particularly subject to biasing and simulation error--such as climate science--it might be wise to reserve judgment until the picture can be clarified by better research.

Hat tip Futurepundit.


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An Optical Trick

Click on this link to get the Google Video larger screen version, then watch it for the full one and a half minutes. You may feel like you're in The Matrix for a few seconds.


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Teenage Risk-Taking: Causes and Explanations

If teenagers drink too much alcohol or take psychoactive drugs in excessive quantities, they risk life-long damage to their ultimate cognitive capacity. Teenagers typically engage in risky behaviour. An interesting question is whether the risky behaviour is caused by society's misguided restrictions on teen activity, or by the lack of activity in the still-developing prefrontal brain regions, or both?
Plenty of adolescent behaviors are annoying, but others can be dangerous or even potentially deadly-- like substance abuse and unprotected sex. Brain researcher Monique Ernst points out that teenagers' propensity for thrill-seeking doesn't just come from having more independence, exposure to risky behaviors, or peer pressure.

"This behavior doesn't come from the environment only," she says. "It is actually very much governed by changes that happen in the brain as the adolescents grow."

Ernst, a researcher and clinician in the National Institute of Mental Health's (NIMH) Mood and Anxiety Disorders Program Branch, says in spite of teens generally being at their peak of health, they have a disproportionately high rate of injury and death.

"Their speed of reaction time is really high, their cognitive function, or their thinking, is pretty good, their athletic ability is great," Ernst says. "So they're really healthy, and at the same time, their rate of being sick or impaired and their rate of [injury and death] is really high.
Risky Teen Brains

The evidence is good that both factors are coming into play to determine much of the risk-taking seen in the teen years.

Many young adults, even middle-aged adults, continue in risk-taking behaviours long after the pre-frontal regions should have myelinated completely, and long after most of the "pruning" of the neocortex will have taken place. Those adults who are drawn to risky professions--the military, high rise construction, various high-risk maintenance jobs, underground mining, racing pilots and drivers, fishermen etc.--likely have "fully meylinated" forebrains, yet still rush to risky behaviours. That is not counting all the lawyers, accountants, dentists, physicians etc. who spend their free time pursuing high risk sports. Most risky of all--using the cell phone while driving--remains to be explained by neuroscience and the behavioural sciences.


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Brain Stem Consciousness: Assessing the Importance of the Neocortex in "Consciousness"

Some of the more promising approaches to AGI are attempting to imitate the modular approach to intelligent neural nets that evolution has taken in mammals. Much of the emphasis (eg numenta) is on the structure of the human neocortex and its connections to midbrain structures. Is it possible that by leaving out the brainstem, that these models are neglecting the essential piece, at least for "conscious" intelligence?
With some notable exceptions (e.g. Scheibel & Scheibel 1977; Panksepp 1982; Thompson 1993; Bogen 1995; Watt 2000; Parvizi & Damasio 2001), brainstem mechanisms have not figured prominently in the upsurge of interest in the nature and organization of consciousness that was ushered in with cognitivism in psychology and neuroscience (Mandler 1975; Miller 1986; Baars 1988). Few cognitivists or neuroscientists would today object to the assertion that “cortex is the organ of consciousness”.1 This is, in a sense, a return to an older view of the supremacy of the cerebral cortex from which a fundamental discovery of the late 1940s had stimulated a partial retreat. In keeping with the sense that the cerebral cortex is the organ of higher functions it had been widely assumed that the regulation of its two primary states – sleep and wakefulness – was a cortical function as well (see, e.g., the critical discussion of this stance in Gamper 1926, pp. 68- 78). Then, in the late 1940s, Moruzzi and Magoun (1949) discovered that local stimulation of circumscribed cell groups in the pons and midbrain of experimental animals exerts a global activating influence on the cerebral cortex as well as on behavioral state, and that experimental lesions in these brainstem sites are capable of rendering animals somnolent and even comatose (Magoun 1954; cf. Parvizi & Damasio 2003). This came as a shock to the corticocentric perspective, and stimulated an avalanche of research on brainstem regulation of sleep and wakefulness and its relationship to the conscious state (summarized in symposium volumes edited by Adrian et al. 1954; Jasper et al. 1958; and Eccles 1966).
Read the entire paper here

Of course, what applies to the study of human consciousness may not apply to the quest for AGI--which may not require consciousness as we understand it. Most of us in medicine or the neurological sciences have run across patients with significant hydrocephalus who are also highly functional, and even highly intelligent in some cases. Their neocortex may be compressed by CSF to very thin dimensions, with minimal if any diminution of consciousness, and/or intelligence.

Still, it is fascinating to mentally rearrange the priority of the various parts of the brain, in terms of importance for "consciousness" or "intelligence." The teenage brain is both conscious and intelligent, while at the same time it is highly plastic and in a state of rapid development. Perhaps it is actually the state of "incompleteness" that makes the teenage brain so potent. I suspect so.

The major criticism of the teenage brain--which is not truly a criticism--is that it lacks independent judgment that comes from experience. The question involved in that particular "criticsim" is: Does the lack of forebrain meylination (pertaining to plasticity) cause the lack of judgment, or is it possible to maintain the plasticity over time while supplying the experience that leads to sound situational judgment?

While many persons are insulted or offended by the idea that the lack of teen judgment may at least in part be accounted for by the plasticity and rapid development of the teen brain, it would be more constructive to look at what can actually be demonstrated by imaging studies and other minimally subjective data.

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15 September 2007

The $100 then $175 now $188 Laptop--Has Anyone Heard of Sharing?

The "One Laptop per Child" project was an interesting idea, but as anyone should have expected, the price has risen well above US $100.
Leaders of the nonprofit One Laptop Per Child that was spun out of MIT acknowledged Friday that the devices are now slated to cost $188 when mass production begins this fall. The last price the nonprofit announced was $176; it described $100 as a long-term goal.

Spokesman George Snell blamed the increase on a variety of factors, including currency fluctuations and rising costs of such components as nickel and silicon. He said the project was committed to keeping the price from rising above $190.

While less than $200 for an innovative, wireless-enabled, hand-powered laptop is a relative bargain, a price nearly twice what the project's memorable nickname promised could make it harder for One Laptop Per Child to sign up international governments as customers. Those governments are expected to give the computers to children for them to keep and tinker with, which the project's founders believe will cause critical thinking and creativity to blossom.

The actual hardware appears to be quite good, for the price, but it is quite likely that aiming for one laptop per child will be not only too expensive, but actually not necessary for optimal learning. What students of the third world need more than one laptop per child, is dedicated, professional teachers along with good learning materials, textbooks, pencils and paper, school buildings, plenty of food to eat, and freedom from disease and war. The laptops should be way down the list, actually.

But there is nothing wrong with sending these laptops, as long as they are sent to governments that will not steal the machines, resell them on the black market, and pocket the money in Swiss bank accounts for corrupt officials. The project's leaders may be guilty not only of excessive price point optimism, but of lack of oversight of the actual conditions of delivery and utilisation.

A computer is not a magic wand. If it were so, the test scores of American students would be quite high, internationally, when instead the scores are quite low.

As the price of these machines continues to grow, it may be necessary to rethink many of the assumptions underlying the overall project. It may be necessary to go slowly, as conditions merit. And it may be necessary for the children to share.


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14 September 2007

Psychological Neoteny and Leaving Adolescence

Adolescence in modern societies is largely an artifact of current childraising and educational techniques. Adolescents are protected from most real world responsibilities, sequestered in schools with others of their age group until their early twenties, and receive minimal supervision and guidance in the acquisition of practical real world skills from "adults" who may or may not have gained a level of wisdom and judgment from their own encounters with the adult world of responsibility.

Current baby-boomers are the first generation to have been raised under the new, pampered, age-isolated and work-restricted regime of child-raising. Baby-boomers have raised their own children under a similar-but-more-so regime of age isolation and sheltering from responsibility. A third generation is currently being raised into this regime.

Besides poor child-raising and a counter-productive educational system, in their quest to become responsible adults, modern youth must also battle against a "youth culture" that encourages binge drinking, psychoactive drug use, and other acts of "rebellion" which may have long-term consequences for their ability to function optimally in a world of personal responsibility.

In earlier America, youth were not treated as adolescents. This online book, The Underground History of American Education, provides an extensive look at earlier educational practises in America. Joseph Kett's Rites of Passage likewise provides an illuminating look at what the education and life of American youths was like prior to the wars of the 20th century. Adolescence as we know it was largely unknown in those times. It is an artifact of modern practises.

Dr. Robert Epstein has looked at this issue extensively, and has written the book The Case Against Adolescence. Epstein has come to the conclusion that adolescents are able to learn most if not all adult competencies and responsibilities--if society would give them a chance. But that is not likely, given current attitudes, educational methods and laws, and childraising techniques--combined with a destructive and corporate controlled "youth culture."

A final complication and confusion for many, is the fact that parts of the human brain do not fully develop, myelinate, and neurologically prune until the mid-twenties. What does this mean? It means that the brains of youth are still "plastic" up until their twenties--still developing. They will lack some forebrain function as youth, which may serve them in good stead at a later age, if they are given the proper training and guidance in the meantime--and do not damage their own neural development through unwise excesses of psychoactive drugs and alcohol.

Then what is "psychological neoteny?" It is merely the end result, in adulthood, of not having learned the lessons of judgment and responsibility in youth that are necessary to live a responsible life of personal competence. A psychological neotenate is a victim of combined dysfunctionalities of society, parents, educational systems, and age-segregation with sheltering from responsiblity.

I refer to psychological neotenates as "lifelong incompetents." The reason for the "lifelong" descriptor is that these "adults" are beyond the age of maximal plasticity of the brain. They have largely lost their chance to grow into responsiblity and competence. Is that an absolute barrier to growth? No. The human brain retains some ability to modify itself, retains stem cells and glial function, well into maturity and beyond. But the youthful brain, with its ongoing myelination and active pruning, remains significantly more plastic until the mid-twenties.

Never has western culture needed competence from its youth more than at this time. The west is being challenged on several fronts--ideologically, demographically, spiritually (recall that I am an atheist, so the concept of "spirituality" will be a broad one), and on current and near-future battlefields.

In North American cultures, and in the UK, there is a general failure of competence-formation among a large proportion of youth. That is the report from large employers, it is the complaint of industries wanting to establish plants inside the US, it is the tale of credit statistics and bankruptcy courts, it is the story of youth and young adults staying with their parents into their twenties and thirties. One must look for the threads of this particular tapestry, because of the rapidity of its flux.

Children are not a Blank Slate. Yet many of the potential abilities and competencies of children and youth, are latent. They must be developed within the proper time windows. If child-rearing and educational practises are not geared toward encouraging development of these latent competencies within the proper time windows, the child will suffer in later life from a lack of these competencies. Of all the educational systems of the world, only the Montessori and similar approaches, acknowledge this critical developmental sequence.

Later youth and early adulthood, with the late development of the forebrain, absolutely requires exposure to multiple philosophies, spiritual approaches, political ideologies, and professional/vocational styles. A failure to expose youth and young adults to a diversity of ideas is the equivalent of an academic lobotomy--an indoctrination or brainwashing rather than an education. We see this academic lobotomy practise commonly at modern universities, in the arts, humanities, and social sciences.

Fortunately, there are alternative paths through life, apart from the dysfunctional educational systems and universities of many western societies. Paths where children are allowed to develop competencies and responsibilities commensurate with their growing abilities.

I will develop this idea more later.

Bonus: Epstein's essay "Let's Abolish High School."

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11 September 2007

Adventures in RF Chemistry--It's not Ice-9

Just hit salt water with radio frequency (RF) waves of the right type, and the hydrogen will separate and burn. John Kanzius discovered this technique by accident in the course of tinkering with RF to cure cancer.

Suggested by Will Brown.

Since we are all made up of large proportions of saltwater ourselves, it might be best not to focus high energy RF waves on ourselves for long periods of time. We might find ourselves bursting into flames!

Remember Kurt Vonnegut's "Ice 9". This invention has the opposite effect on sea water.

Imagine giant satellite RF generators, aiming rays at the enemies' seaports. Or terrorists aiming RF beams at popular beaches, killing thousands in the resulting flames.


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08 September 2007

Choking China Contaminates World, Itself

China has become a pollution disaster of epic proportions--a runaway train of environmental destruction spilling over to contaminate the entire world.
China's rapid development, often touted as an economic miracle, has become an environmental disaster. Record growth necessarily requires the gargantuan consumption of resources, but in China energy use has been especially unclean and inefficient, with dire consequences for the country's air, land, and water.

The coal that has powered China's economic growth, for example, is also choking its people. Coal provides about 70 percent of China's energy needs: the country consumed some 2.4 billion tons in 2006 -- more than the United States, Japan, and the United Kingdom combined. In 2000, China anticipated doubling its coal consumption by 2020; it is now expected to have done so by the end of this year. Consumption in China is huge partly because it is inefficient: as one Chinese official told Der Spiegel in early 2006, "To produce goods worth $10,000 we need seven times the resources used by Japan, almost six times the resources used by the U.S. and -- a particular source of embarrassment -- almost three times the resources used by India."

Meanwhile, this reliance on coal is devastating China's environment. The country is home to 16 of the world's 20 most polluted cities, and four of the worst off among them are in the coal-rich province of Shanxi, in northeastern China. As much as 90 percent of China's sulfur dioxide emissions and 50 percent of its particulate emissions are the result of coal use.

Pollution is also endangering China's water supplies. China's ground water, which provides 70 percent of the country's total drinking water, is under threat from a variety of sources, such as polluted surface water, hazardous waste sites, and pesticides and fertilizers. According to one report by the government-run Xinhua News Agency, the aquifers in 90 percent of Chinese cities are polluted. More than 75 percent of the river water flowing through China's urban areas is considered unsuitable for drinking or fishing, and the Chinese government deems about 30 percent of the river water throughout the country to be unfit for use in agriculture or industry. As a result, nearly 700 million people drink water contaminated with animal and human waste.

...Recent Chinese studies of two of the country's most important sources of water -- the Yangtze and Yellow rivers -- illustrate the growing challenge. The Yangtze River, which stretches all the way from the Tibetan Plateau to Shanghai, receives 40 percent of the country's sewage, 80 percent of it untreated. In 2007, the Chinese government announced that it was delaying, in part because of pollution, the development of a $60 billion plan to divert the river in order to supply the water-starved cities of Beijing and Tianjin. The Yellow River supplies water to more than 150 million people and 15 percent of China's agricultural land, but two-thirds of its water is considered unsafe to drink and 10 percent of its water is classified as sewage. In early 2007, Chinese officials announced that over one-third of the fish species native to the Yellow River had become extinct due to damming or pollution.

Japan and South Korea have long suffered from the acid rain produced by China's coal-fired power plants and from the eastbound dust storms that sweep across the Gobi Desert in the spring and dump toxic yellow dust on their land. Researchers in the United States are tracking dust, sulfur, soot, and trace metals as these travel across the Pacific from China. The U.S. Environmental Protection Agency estimates that on some days, 25 percent of the particulates in the atmosphere in Los Angeles originated in China. Scientists have also traced rising levels of mercury deposits on U.S. soil back to coal-fired power plants and cement factories in China. (When ingested in significant quantities, mercury can cause birth defects and developmental problems.) Reportedly, 25-40 percent of all mercury emissions in the world come from China.

What China dumps into its waters is also polluting the rest of the world. According to the international NGO the World Wildlife Fund, China is now the largest polluter of the Pacific Ocean. As Liu Quangfeng, an adviser to the National People's Congress, put it, "Almost no river that flows into the Bo Hai [a sea along China's northern coast] is clean." China releases about 2.8 billion tons of contaminated water into the Bo Hai annually, and the content of heavy metal in the mud at the bottom of it is now 2,000 times as high as China's own official safety standard. The prawn catch has dropped by 90 percent over the past 15 years. In 2006, in the heavily industrialized southeastern provinces of Guangdong and Fujian, almost 8.3 billion tons of sewage were discharged into the ocean without treatment, a 60 percent increase from 2001. More than 80 percent of the East China Sea, one of the world's largest fisheries, is now rated unsuitable for fishing, up from 53 percent in 2000.
Read the entire story at Foreign Affairs.

The fallout for China's government over this massive environmental debacle will be severe, unless the leadership can focus the population's attention onto other matters--such as a war with Taiwan, or other neighbors. War is typically the way that corrupt leaders unite a disaffected population behind them, despite enormous mismanagement of resources.

If the government can stoke a latent hyper-nationalism and xenophobia among enough of its people, it may be able to avoid facing the consequences of its devastating contamination of China's air and water.


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Virtual Schools---Growing 25% Yearly, Already a Million Student Strong

Government schools in North America have failed children, parents, and taxpayers. Faced with the prospect of countless future generations of incompetent ignoramuses, a few visionary educators set about to create a system for the future--Virtual Schools.
As a seventh-grader, Kelsey-Anne Hizer was getting mostly D's and F's and felt the teachers at her Ocala middle school were not giving her the help she needed. But after switching to a virtual school for eighth grade, Kelsey-Anne is receiving more individual attention and making A's and B's. She's also enthusiastic about learning, even though she has never been in the same room as her teachers.

...virtual schools are growing fast - at an annual rate of about 25 percent. There are 25 statewide or state-led programs and more than 170 virtual charter schools across the nation, according to the North American Council for Online Learning.

...virtual learning has almost unlimited potential. Many envision a blending of virtual and traditional learning.

"We hope that it becomes just another piece of our public schools' day rather than still this thing over here that we're all trying to figure out," said Julie Young, Florida Virtual's president and CEO.

Florida Virtual is one of the nation's oldest and largest online schools, with more than 55,000 students in Florida and around the world, most of them part-time. Its motto is "Any Time, Any Place, Any Path, Any Pace."

...Casey Hutcheson, 17, finished English and geometry online in the time it would have taken to complete just one of those courses at his regular high school in Tallahassee.

"I like working by myself because of no distractions, and I can go at my own pace rather than going at the teacher's pace," he said.

While teacher's unions and other backward looking vested interests attempt to have virtual schools and charter schools shut down, virtual education for all ages is actually just getting started. Several states have endorsed and adopted virtual schooling, including Florida and Wisconsin.


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06 September 2007

Naked Glacier Dwellers In Danger of Extinction from Global Warming

A tribe of naked glacier dwellers was recently discovered in the middle of a mass trans-glacial migration, by wildlife photographers high in a remote portion of the Swiss Alps. The ice-dwelling tribe comprises almost six hundred naked members, who apparently speak only body language for communication.

Highly trained anthropologists from Greenpeace were rushed to the scene in an attempt to discover the tribe's history and customs, before the glaciers vanish and the tribe goes extinct. The Greenpeace scientists quickly shed their own clothes, in a desperate attempt to establish communication, as the clock ticks down on global warming.

As of our last radio transmission, all attempts at establishing body language communication had been unsuccessful--perhaps because the proximity to the glacier induced uncontrollable shivering and shrinkage of certain body tissues of the researchers. The message conveyed to the tribe by the shivering shrinkage apparently repulsed all members of the tribe, who significantly turned their backs on the scientists. At that very moment, an eerie yodeling sound echoed from the surrounding peaks, as if the glaciers themselves had cried out in pain.

Al Gore, James Hansen, Bono, Laurie David, and Leonardo di Caprio announced a joint filmmaking expedition to explore and preserve this courageous tribe in the fight for its very existence. "For at least three long ice ages and inter-glacials this care-free tribe led an idyllic existence among the clouds," said Gore. "We hope that their sad story will shame all of those who deny the global warming holocaust, those traitors to the children of Gaia."

All of us can only echo Mr. Gore's sentiments, and wish the very best for the naked glacier dwellers in the sky. Even after they are extinct, we will never forget the ice people and their brave struggle.

Hat tip Lubos

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New Volvo Pluggable Concept Car Has No Driveshaft or Transmission--60 Miles on a 3 Hour Charge

Before you get too excited, you should know that this car will not see production before 2015 at the soonest. The four independent electric motors are built into the wheels, and the only power connection to the wheels is a power cable from the battery. The 1.6 liter flex-fuel engine is only there to keep the batteries charged.
When fully charged the Volvo ReCharge Concept can be driven approximately 62 miles on battery power alone before the car's four-cylinder 1.6 Flexifuel engine1 is needed to power the car and recharge the battery. The concept car also retains the Volvo C30's lively and sporty drive thanks to an acceleration figure of 0-62mph in 9 seconds and a top speed of 100mph.

"This is a groundbreaking innovation for sustainable transportation. This plug-in hybrid car, when used as intended, should have about 66 percent lower emissions of carbon dioxide compared with the best hybrid cars available on the market today. Emissions may be even lower if most of the electricity comes from CO2-friendly sources such as biogas, hydropower and nuclear power. A person driving less than 60 miles per day will rarely need to visit a filling station.

...During a journey the combustion engine starts up automatically when 70 percent of the battery power has been used up. However, the driver also has the option of controlling the four-cylinder Flexifuel engine manually via a button in the control panel. This allows the driver to start the engine earlier in order to maximise battery charge, for instance when out on a motorway in order to save battery capacity for driving through the next town.

* The battery pack integrated into the boot uses lithium-polymer battery technology. The batteries are intended to have a useful life beyond that of the car itself.
* Four electric motors, one at each wheel, provide independent traction power.
* Four-cylinder 1.6-litre Flexifuel engine drives an advanced generator that efficiently powers the wheel motors when the battery is depleted.

...The central electrical components in the Volvo ReCharge Concept – the generator for the APU and the wheel motors – were developed together with British electromagnetic specialists PML Flightlink.

With an individual electric motor at each wheel, weight distribution as well as mechanical efficiency and traction are maximised and the friction in mechanical gears is eliminated. Since the car does not have the transmission found in ordinary cars, there is no need for a gear lever.

...The energy that is generated during braking is transmitted to the battery pack. When the system is ultimately developed, traditional wheel brakes will be completely replaced by electrical brakes with minimal energy wasted through friction. To ensure reliable operation of the drivetrain and braking system, driver inputs are fed into a quadruple-redundant electronic control system.
Hat tip Gizmag

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Serotonin Receptor Agonists: Better than SSRI's?

Serotonin has been shown to be important in depression and anxiety. But what is the best "serotonin approach" to treating depression? SSRIs (selective serotonin reuptake inhibitors) such as Prozac are generally effective, but may take several weeks to achieve maximum effect. Another approach is for a drug to directly stimulate serotonin receptors--serotonin (5HT) agonists.

Recent research into 5HT4 receptor agonists, using rats as subjects, appears to promise faster and more efficacious serotonergic antidepressants.
Antidepressants that directly enhance serotonin signaling appear to have a much faster onset of action in animal models of depression than selective serotonin reuptake inhibitors (SSRIs), said investigators here.

Rats given one of two serotonin -- (HT4) agonists -- a new class of drug-showed behaviors and brain changes within three days that were suggestive of antidepressant effects that would take two to three weeks to achieve with an SSRI, reported Guillaume Lucas, Ph.D., of McGill University, and colleagues in the Sept 6 issue of Neuron.

The authors provide "and extensive and convincing data set" suggesting that this new class of molecules is fasting-acting and potentially efficacious, but whether they will see the light of day as therapies for human depression is still unknown, cautioned Ronald S. Duman, Ph.D., of Yale, in an accompanying editorial.

"These agents will require extensive testing in clinical trials for confirmation, because of limitations inherent in rodent models of depression and antidepressant response and because of potential side effects," Dr. Duman wrote.

The important thing to remember is that although some humans may behave like rats, humans are not rats. Research on models of depression in rats may not transfer directly to good results in humans. Drug safety in humans and drug safety in rats are certainly not the same, either.

In an area of therapeutics such as depression, regulatory agencies will likely require extensive clinical studies before approval. It is important to point out, however, that depression is a potentially fatal disease. Any drug that promises rapid emergence from deep clinical depression, and which is also safe for short to intermediate term use, may find an important function in the treatment of depression--even if it is not approved for long term use.

This is an interesting result of the study:
They found that the action of the drugs on the 5-HT4 receptor "deeply modified" serotonin transmission by enhancing firing of dorsal raphe neurons in the hippocampus. In addition, three days of treatment also significantly promoted neurogenesis in the subgranular zone of the dentate gyrus of the hippocampus, an effect normally seen after a minimum of two weeks of treatment with classical antidepressants or SSRIs.

If depression kills neurons, and effective antidepressant therapy promotes new neuron growth, the new approach to stimulating serotonin receptors appears to do its formative work on neuronal stem cells more quickly than SSRIs.

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04 September 2007

Will The Singularity Founder on Differences Between the Brain and Computers?

The Singularity Summit is occurring on 8-9 September 2007 in San Francisco, this weekend. It will be attended by people who are largely optimistic about the chances for a Technological Singularity within the next 20 years, triggered by the development of artificial general intelligence (AGI). But is that optimism well supported? Do researchers in machine intelligence really understand intelligence well enough to create intelligent machines?

One metaphor that has seen a great deal of use among AGI hopefuls, is "the brain is a computer: a computer is a brain." Is that metaphor valid--or even useful--for creating an intelligent machine?

Chris Chatham, a grad student in cognitive science, and proprietor of Developing Intelligence blog, posted an interesting comparison between brains and computers at the end of March, 2007. It may be instructive to re-visit Chris' comparison:
Difference # 1: Brains are analogue; computers are digital

It's easy to think that neurons are essentially binary, given that they fire an action potential if they reach a certain threshold, and otherwise do not fire. This superficial similarity to digital "1's and 0's" belies a wide variety of continuous and non-linear processes that directly influence neuronal processing.

Difference # 2: The brain uses content-addressable memory

In computers, information in memory is accessed by polling its precise memory address. This is known as byte-addressable memory. In contrast, the brain uses content-addressable memory, such that information can be accessed in memory through "spreading activation" from closely related concepts. For example, thinking of the word "fox" may automatically spread activation to memories related to other clever animals, fox-hunting horseback riders, or attractive members of the opposite sex.

The end result is that your brain has a kind of "built-in Google," in which just a few cues (key words) are enough to cause a full memory to be retrieved. Of course, similar things can be done in computers, mostly by building massive indices of stored data, which then also need to be stored and searched through for the relevant information (incidentally, this is pretty much what Google does, with a few twists).

Difference # 3: The brain is a massively parallel machine; computers are modular and serial

An unfortunate legacy of the brain-computer metaphor is the tendency for cognitive psychologists to seek out modularity in the brain. For example, the idea that computers require memory has lead some to seek for the "memory area," when in fact these distinctions are far more messy. One consequence of this over-simplification is that we are only now learning that "memory" regions (such as the hippocampus) are also important for imagination, the representation of novel goals, spatial navigation, and other diverse functions.

Similarly, one could imagine there being a "language module" in the brain, as there might be in computers with natural language processing programs. Cognitive psychologists even claimed to have found this module, based on patients with damage to a region of the brain known as Broca's area. More recent evidence has shown that language too is computed by widely distributed and domain-general neural circuits, and Broca's area may also be involved in other computations (see here for more on this).

Difference # 4: Processing speed is not fixed in the brain; there is no system clock

The speed of neural information processing is subject to a variety of constraints, including the time for electrochemical signals to traverse axons and dendrites, axonal myelination, the diffusion time of neurotransmitters across the synaptic cleft, differences in synaptic efficacy, the coherence of neural firing, the current availability of neurotransmitters, and the prior history of neuronal firing. Although there are individual differences in something psychometricians call "processing speed," this does not reflect a monolithic or unitary construct, and certainly nothing as concrete as the speed of a microprocessor. Instead, psychometric "processing speed" probably indexes a heterogenous combination of all the speed constraints mentioned above.

Difference # 5 - Short-term memory is not like RAM

Although the apparent similarities between RAM and short-term or "working" memory emboldened many early cognitive psychologists, a closer examination reveals strikingly important differences. Although RAM and short-term memory both seem to require power (sustained neuronal firing in the case of short-term memory, and electricity in the case of RAM), short-term memory seems to hold only "pointers" to long term memory whereas RAM holds data that is isomorphic to that being held on the hard disk. (See here for more about "attentional pointers" in short term memory).

Difference # 6: No hardware/software distinction can be made with respect to the brain or mind

For years it was tempting to imagine that the brain was the hardware on which a "mind program" or "mind software" is executing. This gave rise to a variety of abstract program-like models of cognition, in which the details of how the brain actually executed those programs was considered irrelevant, in the same way that a Java program can accomplish the same function as a C++ program.

Unfortunately, this appealing hardware/software distinction obscures an important fact: the mind emerges directly from the brain, and changes in the mind are always accompanied by changes in the brain. Any abstract information processing account of cognition will always need to specify how neuronal architecture can implement those processes - otherwise, cognitive modeling is grossly underconstrained. Some blame this misunderstanding for the infamous failure of "symbolic AI."

Difference # 7: Synapses are far more complex than electrical logic gates

Another pernicious feature of the brain-computer metaphor is that it seems to suggest that brains might also operate on the basis of electrical signals (action potentials) traveling along individual logical gates. Unfortunately, this is only half true. The signals which are propagated along axons are actually electrochemical in nature, meaning that they travel much more slowly than electrical signals in a computer, and that they can be modulated in myriad ways. For example, signal transmission is dependent not only on the putative "logical gates" of synaptic architecture but also by the presence of a variety of chemicals in the synaptic cleft, the relative distance between synapse and dendrites, and many other factors. This adds to the complexity of the processing taking place at each synapse - and it is therefore profoundly wrong to think that neurons function merely as transistors.

Difference #8: Unlike computers, processing and memory are performed by the same components in the brain

Computers process information from memory using CPUs, and then write the results of that processing back to memory. No such distinction exists in the brain. As neurons process information they are also modifying their synapses - which are themselves the substrate of memory. As a result, retrieval from memory always slightly alters those memories (usually making them stronger, but sometimes making them less accurate - see here for more on this).

Difference # 9: The brain is a self-organizing system

This point follows naturally from the previous point - experience profoundly and directly shapes the nature of neural information processing in a way that simply does not happen in traditional microprocessors. For example, the brain is a self-repairing circuit - something known as "trauma-induced plasticity" kicks in after injury. This can lead to a variety of interesting changes, including some that seem to unlock unused potential in the brain (known as acquired savantism), and others that can result in profound cognitive dysfunction (as is unfortunately far more typical in traumatic brain injury and developmental disorders).

Difference # 10: Brains have bodies

This is not as trivial as it might seem: it turns out that the brain takes surprising advantage of the fact that it has a body at its disposal. For example, despite your intuitive feeling that you could close your eyes and know the locations of objects around you, a series of experiments in the field of change blindness has shown that our visual memories are actually quite sparse. In this case, the brain is "offloading" its memory requirements to the environment in which it exists: why bother remembering the location of objects when a quick glance will suffice? A surprising set of experiments by Jeremy Wolfe has shown that even after being asked hundreds of times which simple geometrical shapes are displayed on a computer screen, human subjects continue to answer those questions by gaze rather than rote memory. A wide variety of evidence from other domains suggests that we are only beginning to understand the importance of embodiment in information processing.

Bonus Difference: The brain is much, much bigger than any [current] computer

Accurate biological models of the brain would have to include some 225,000,000,000,000,000 (225 million billion) interactions between cell types, neurotransmitters, neuromodulators, axonal branches and dendritic spines, and that doesn't include the influences of dendritic geometry, or the approximately 1 trillion glial cells which may or may not be important for neural information processing. Because the brain is nonlinear, and because it is so much larger than all current computers, it seems likely that it functions in a completely different fashion. (See here for more on this.) The brain-computer metaphor obscures this important, though perhaps obvious, difference in raw computational power.
Developing Intelligence
I must urge anyone interested in this topic to read Chris' posting as linked above in its entirety, without the "snips." And by all means, read the fascinating comments, where you will almost inevitably find your own point of view, if you disagree with Chris' points above.

There other differences--perhaps as important as Chris' points, or even more so--that are worth discussing at a later time. My POV is that the conceptual basis for the necessary machine substrate for intelligence has not yet been conceptualized. Doing that will require extensive knowledge of how the human brain--the only known "intelligent" device in the known universe--actually achieves a modicum of intelligence.

Jeff Hawkins, author of On Intelligence, may have the best head start of anyone in the running. But Hawkins is not aiming for a "Singularity-spawning AGI." His immediate goals are much more modest--thus more likely to be achieved.

For anyone with an interest in the Tech Singularity, consider attending the Singularity Summit this weekend in SF, CA, if you can. Failing that, check Michael Anissimov, CRNano, or the Singularity Institute to find someone liveblogging the event.

The Singularity Institute has several publications online dealing with AGI. In my opinion, the approaches to AGI advocated in the SIAI readings are suitable mainly for "probabilistic co-processing", rather than for any "main processor" of consciousness. But read them yourself, and see how you feel.

If the people working on AGI are working with a faulty metaphor of how intelligence can be created, the road to the AGI-instigated singularity may be a long one.

More: For those who want to try to get up to speed on current attempts to approximate AGI, see here and here.

Even More: Here are online video lectures on machine learning/AI, and here is David MacKay's book on information theory, inference, and learning algorithms for download as an entire book, or as individual chapters.

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