* 22 entries including: road infrastructure, THE MAKING OF THE FITTEST, Chinese social problems, trees & global warming, cybersafety rethought, hemp for victory, DNA analysis for conservation, more on Second Life, bogus statistical analysis in medicine, money transfers for developing-world cellphone users, carbon nanonets, North Korean intranet, vaccines against recreational drugs, fuels from algae, and varmints in space.
* THE CHINA PROBLEM: Anyone who watches the news much knows that China's growth into a world economic superpower has not been without its difficulties -- tainted food and medicine, unsafe tires, product piracy, environmental pollution, exploitation of workers, and poor health care. According to an article in BUSINESS WEEK ("Broken China" by Pete Engardio, Dexter Roberts, Frederick Balfour, and Bruce Einhorn, 23 July 2007), things are likely to get worse before they get better.
The problems understandably are rooted in the conversion of a state-run economy into a commercial powerhouse in a few decades. China's leadership is perfectly aware of them, with President Hu Juntao repeatedly calling for a "harmonious society" -- implying that's not what China has now. Unfortunately, the growth-at-all-costs mindset led the leadership to skimp on health care and an effective regulatory apparatus. Worse, even though the leadership knows that China must change, senior officials sit on top of a pyramid of bureaucrats that not only is much too cozy with the businesses they are supposed to be keeping under control, but is also saddled with Party directives to "get [economic] results" that work against the calls for reform.
The government is trying to fix things, with regulators shutting down illegal food producers, passing new environmental regulations, cracking down on product piracy, and arresting tens of thousands of officials for corruption -- leading to the occasional high-profile execution. However, it's an uphill battle. For example, a few years ago 92% of the software used in China was pirated; a regulation requiring government employees to use legitimate software has cut piracy -- to 82%.
Chinese laws are actually prudent on paper, and the government is not particularly short of money to implement programs. The basic problem is with the "local emperors", the local officials who actually have to get things done. They're not only presented with very strong temptations for corruption, the system tends to encourage it because the government is so strongly involved in business.
At this point, the "other" China problem, authoritarianism, comes into play. While corruption can be widespread in representative governments, it seems to be a particular affliction of authoritarian regimes. How could it be otherwise, given a system that undermines public accountability and tends to assume the citizenry serves the state -- not the other way around? It's hard to feel much confidence in Chinese reform while the Party remains committed to a monopoly on power and repression of dissent, taking enormous effort to monitor internet traffic while killer medicines go out the door unnoticed.
* ED: A recent article in THE ECONOMIST amplified on some of the Chinese product quality problems. The biggest problem is with small fly-by-night subcontractors, and so multinationals operating in the country are increasingly careful to maintain control over their subcontractor supply chain. Coca-Cola does not allow subcontractors to subcontract again. McDonald's, always efficient, has its own complete supply chain in China, with more than 40 facilities to handle beef, chicken, lettuce, cucumbers, rolls, and special sauce. Enterprising Chinese firms, such as Li & Fung, provide subcontractor monitoring services for a fee.BACK_TO_TOP
* THE MAKING OF THE FITTEST (16): One last topic worth covering in evolutionary genetics is the subject of "evolutionary development" or just "evo devo" for short. It's actually a very big subject in itself, but it's also elaborate, and so it's only discussed briefly here.
Back in the 1950s, when modern evolutionary theory was being assembled and DNA was a new concept, the general assumption was that when heredity was finally unraveled in detail, the genomes of different creatures would be as entirely different as their appearance -- it would be expected that the genes of the fruitfly and the dolphin would have very little in common. By the 1980s, it was becoming apparent that the logic of the genetic "machinery" underlying all organisms actually has strong common elements, particularly in terms of the genes that control development of an organism through its embryonic stages.
For example, the development of the eye is dependent on a gene designated Pax-6 -- some other developmental genes are also involved, but they will be ignored here for simplicity. The interesting thing is that the development of the eye in all animals, no matter if the eye is that of a mantis or a spider or a squid or a human, is dependent on Pax-6. There are other "developmental" genes, the best known being the "homeobox" or Hox genes, which control the arrangement of body parts.
These genes don't really construct anything themselves, they just tell other genes in the genome to build the appropriate structure. For instance, developmental genes provide commands to direct the construction of our five fingers, all using the same low-level genetic routine. Sometimes the developmental gene gets it wrong, and the result is six fingers. It's not unknown in humans, and six-toed cats are fairly common -- they can be spotted because of their oversized paws. Mutations in developmental genes can often be disastrous and lethal, but they clearly can be useful as well: snakes have hundreds of ribs, far more than the legged reptiles that were their ancestors, and it doesn't require much imagination to see how errors in developmental genes gave them their vastly extended ribcage, providing them with a body that could get around efficiently without legs. Centipedes and millipedes demonstrate a similar repetition in body structure.
The significant thing about the developmental genes is their universality: they are immortal genes common among the animals. In essence, they define a core "machine", established before life ever emerged from the sea, that is manifested in a bewildering range of organisms. Those who believe in Design instead of evolution can rightfully suggest that this arrangement is consistent with Design, that the Designer set up this core machine at the outset. However, those who accept evolution can point out that this commonality among organisms makes evolution by natural selection more plausible, since instead of requiring a unique genetic design for highly different organisms, they are all modifications in the operation of a common engine -- less diverse under the skin than they look from the outside.
In fact, by tracing the variations in operation of this common engine in different organisms, we can in principle obtain a map or "video" of the precise branching paths in the developmental evolution of those organisms, showing exactly the mutations that led from one organism to another. To be sure, that map is a big job, but we have the basic tools for doing it and there is no visible obstacle to filling it out other than time and effort. [TO BE CONTINUED]START | PREV | NEXT
* INFRASTRUCTURE -- ROADS (4): Traffic doesn't always stay on the road, and so roadways often have barriers to prevent straying cars from falling down ravines, drifting into oncoming traffic, and so on. The problem is devising a rail that has a certain amount of "give", ensuring that it neither smashes a car striking it any more than necessary, nor bounces it back into traffic.
The most familiar scheme is a rail in the form of a steel beam with a "W" shaped cross section. The rail is mounted on posts using standoffs to help keep a vehicle from wrapping itself around the posts. Wire cable standoffs are used as well, sometimes with springs built into the cable anchorages to improve its shock-absorbing properties. Heavy concrete or steel pipe barriers are only used when running off the road would lead to a massive disaster. Guardrails tend to impale vehicles that hit then on an end, so the ends of modern W-style guardrails tend to be curved away from the road in one orientation or another. Sometimes shock absorbing panels are mounted on the ends.
Since crossing over into high-speed oncoming traffic can be catastrophic, and so sectioned concrete dividers known in the USA as "New Jersey barriers" -- though they seem to have originated in California -- are sometimes placed on the median. They have a tapered configuration that is designed to shove a vehicle back without flipping it over.
"Crash cushions" are often placed on the end of bridge abutments, retaining walls, and the "gore area" where an off ramp diverts off a freeway. Crash cushions are often barrels filled with sand or water, held in place by cables, but old tires work, too. Signposts next to high-speed traffic lanes are usually mounted on bolts or rivets that allow them to shear away easily if struck by a vehicle. It's not easy to build wooden poles that shear away easily and so they are usually not sited close to traffic. Similarly, pole systems that carry heavy overhead signs are kept back from the roadway, since if they had shear systems they would likely fall over on their own in a strong wind. In big cities, the poles carrying heavy overhead signs are sometimes protected by coils of razor wire to prevent spraycan-carrying "taggers" from crawling up them to deface the signs.
On roads through mountains, runaway truck lanes are set up just off the roadway to deal with big rigs that have lost their brakes on a downgrade. The lanes are covered with sand or gravel to bog down the truck, and lead to an upgrade when possible. [TO BE CONTINUED]START | PREV | NEXT
* GIMMICKS & GADGETS: According to BUSINESS WEEK, a computer-vision company named GestureTek in Sunnyvale, California, has developed software that allows users of camera phones to play cellphone games in which they throw darts or roll a marble through a maze just by tilting the phone. GestureTek is working on improved software that will allow users to skip from page to page in a phone website just with flicks of the wrist, and ultimately plans to allow users to interact by gesturing with a finger in front of the phone.
* BBC WORLD Online reported on a unique and interesting system now being put to use in what used to be East Germany. When the Berlin Wall fell in 1989, the Stasi, the notoriously efficient East German security service, went into overtime tearing up and shredding documents concerning informants and victims. A total of 16,250 sacks full of pieces of 45 million documents were found, and in 1995 a program began to try to piece them back together. Since then, a team of 24 staffers have been able to reconstruct 323 sacks. At that rate, it would take 600 years to go through all the sacks.
Now, thanks to a system developed by the Frauenhofer Institute For Production Systems & Design Technology in Berlin with financial help from the German government, the rate of reconstruction has now accelerated dramatically. In the system, the pieces of the documents are fed through a scanner, and then software tries to match them up, using cues such as paper color, fonts, and so on. The job is expected to be done in five years.
* BBC WORLD Online also reported on US Army work on the "Battlefield Extraction Assist Robot (BEAR)", which can traverse rough terrain on tracked legs to pick up a casualty with hydraulic arms, capable of lifting 225 kilograms (500 pounds). It has gyro and computer control systems to allow it to navigate over rough ground, pick up a wounded soldier gently, and then return the soldier for medical treatment. It can get through doorways and even handle stairs.
The BEAR is being developed by Vecna Technologies on an army contract. It is remotely operated, with cameras and microphones to let the operator know what's going on. It is not capable of fully autonomous operation, though it is smart enough to handle the fiddly small details of moving around on its own. It is fitted with a face resembling that of a teddy bear -- a wounded soldier is not likely to be a good mental state and might well find being picked up by a machine that looks like a Terminator less than reassuring. The current BEAR is a rough prototype, and the robot is expected to be ready for trials in five more years.BACK_TO_TOP
* EVIL TREES? A year ago a scientific study called into doubt the green virtues of planting trees. According to an article in SCIENTIFIC AMERICAN Online ("Are Plants Really Villains in Climate Change?" by Meredith Knight), it's safe to be green again. In 2006, geochemist Frank Keppler of the Max Planck Institute for Chemistry in Mainz, Germany, reported that trees emit large quantities of methane, which is over 20 times more potent a greenhouse gas than the carbon dioxide that the trees soak up. Now a study by botanist Tom Dueck and his colleagues at Plant Research International in Wageningen, the Netherlands, found that methane emissions from plants were down in the noise, that the concentrations "were so low and variable that they did not significantly differ from zero."
In reality, although Keppler's work has often been cited by climate-change deniers as supporting their case, he never claimed the methane emissions from trees were any real problem. The emissions were large in absolute terms, but only a small fraction of the amount of CO2 sequestered by the tree, degrading the benefit of the tree by only 4% at most. Dueck improved on Keppler's study by growing plants using CO2 with the isotope carbon-13 instead of the normal carbon-12, allowing inputs to be traced back to outputs and permitting more accurate measurement. Dueck's measurements cut the methane output to next to nothing.
Keppler claims that use of carbon-13 might have interfered with plant function and thrown of the measurements. However, other researchers have grown plants using CO2 based on carbon-13 for about two decades and have seen no anomalies associated with its use. Dueck shot back that Keppler's methodology may have been faulty, exposing the test plants to stresses that "cooked" them and emitted methane. The dispute, however, is only of academic interest, having little impact on climate modeling one way or another.
ED: There are also models that claim planting of evergreens in snowy regions increases global warming. This is because snow tends to slough off evergreens, leaving the forest dark and able to soak up more solar heat. It's not a problem with deciduous trees, since they lose their leaves before the snow starts falling.
Some critics have used such waffling to call all global-warming science into doubt. I shrug. We're in the relatively early days of considering the issue and the scientific community is still hashing things out among themselves. Researchers will come up with various ideas -- some won't pan out and will be tossed, others will be validated. Things will gradually converge to a consensus. How else would things work?BACK_TO_TOP
* RETHINKING CYBERSAFETY: Anybody who's ever used an antivirus utility knows they can be intrusive and not necessarily all that effective. According to a BBC WORLD Online article ("Staying Safe Without Anti-Virus" by Mark Ward), some users are seeking alternative forms of protection against malicious software or "malware".
Brent Rickels, who handles IT for the First National Bank of Bosque County Texas, ended up tossing his antivirus software. Rickels explains: "I just wanted to be able to sleep at night ... Anti-virus is such a reactive model. The bad guys out there have copies of Symantec and Trend Micro and all of the antivirus software and are using it to develop their stuff on and get their stuff past it." As the primary defense, the bank now uses a "whitelist" system obtained from computer security firm Secure Wave, which simply prevents any but authorized software from running on the bank's PCs. Says Rickels: "It's a lot less work to me than making sure everyone has updated versions of the antivirus." The system is a bit restrictive, for example blocking use of instant messaging: "It's just was not worth it. Nobody has had a good case or need for that in our organization."
The problem with antivirus software is that it is blind to new threats: the software recognizes the "signatures" of malware programs, and so it cannot identify malware that hasn't been seen before. Malicious hackers are always introducing new viruses and have in fact developed "polymorphic" viruses that feature components with no function other than to baffle antivirus programs through continuous random modifications. Other new tactics against viruses don't focus on signatures. Sana Security, for example, has developed software that monitors activities of programs running on a PC, and identifies programs that take actions that seem hostile. The war goes on.
ED: The article also talked about virus writers porting their products to Microsoft Vista. Vista has more protections against viruses, for example refusing to install software without obtaining user permission, but few deny that its protection schemes can be subverted.
I tried to upgrade to Vista, incidentally, but it refused to install -- I needed 512 megabytes of memory, preferably a gigabyte, and all I had was 256 megabytes. I felt a little out-of-date because my mindset was back in the past when a megabyte of memory was a big thing, and it never occurred to me that 256 megabytes of memory would be too small. It still seems hard to believe. One of the nice things about the XO "$100 PC" is that it provides all useful functionality in a minimal package. It seems that much of the whizzy functionality of Windows / Vista is just bells and whistles that few really use and wouldn't be much missed if they weren't there.
In fact, I was reading a review of Vista in BUSINESS WEEK that denounced it as a slow, clumsy pig, claiming that it didn't run well in any less than 2 gigabytes of RAM and that its security features were cumbersome to the point of unworkable. OK, I'm not traditionally an MSoft basher, but enough is enough. I suspect one of the objectives of the Linux OS faction supporting the XO effort is to get a customer and applications base where Linux can seriously take on MSoft as a PC operating system -- and if they can offer an OS that's less complicated, less of a hog, and more reliable I'll jump on board myself.BACK_TO_TOP
* THE MAKING OF THE FITTEST (15): Having considered the genetic evidence for evolution in various animals, it is worthwhile to go on to consider it for humans. One of the most obvious of variable human features is skin color, and it is also obvious that people from the tropics tend to have darker skin. The darkness of skin color is due to production of a pigment named "melanin", which acts as a natural sunblock -- dark-skinned people can still get sunburned, but not anywhere as easily as light-skinned people. Light-skinned people will tend to increase production of melanin under sunny conditions, acquiring a tan. However, a degree of sunlight is necessary to stimulate production of vitamin D and increased production of melanin works against that.
Melanin is produced by cells called "melanocytes". The human pituitary gland creates a melanin-stimulating hormone that binds to a "melanocortin-1 receptor (MC1R)" protein on the melanocytes to ramp up melanin production. The MC1R receptor is produced from an MC1R gene, and this gene varies with human populations. In Europeans and Asians, there are thirteen different MC1R codings that produce ten different varieties of MC1R proteins. In Africans, there are five different MC1R codings, and they all produce exactly the same MC1R protein.
This difference would be very hard to explain as a matter of random chance: it is clear that the MC1R gene in Africans is subjected to greater selection pressure than it is the same gene in Europeans and Asians. It is unclear if the variability of the MC1R gene in Europeans and Asians is due to relaxed selection -- it isn't critical any more -- or positive selection -- lighter skin is needed to ensure vitamin D production in lands with less sunlight.
* Another well-known example of human genetic variability is "sickle-cell anemia", a hereditary disorder that gives its sickle-shaped red blood cells, in contrast to normal donut-shaped red blood cells. The disease was discovered in 1910; once genetic rules of inheritance were sorted out, it was realized that sickle-cell victims inherited the trait from both parents. If a subject only got the trait from one parent, it would lead to some symptoms under special circumstances. In 1948, Linus Pauling discovered that the sickle shape was due to the fact that the hemoglobin was different in the two forms of cells.
In 1949, a Kenyan-born Briton named Anthony Allison performed field studies in Kenya, taking blood samples of local tribesfolk. He found that the sickle-cell trait was very common, 20% or more, among tribesfolk near Lake Victoria or the coastal regions, but very rare, less than a percent, for tribesfolk in dry or highland regions. In a flash of insight, he wondered if the sickle-cell trait was linked to the prevalence of malaria in low-lying, moist areas, where malaria-carrying mosquitoes were common.
After obtaining a medical degree, Allison went back to East Africa in 1953 to test out his idea. He determined that subjects with only one sickle-cell trait were more resistant to malaria, and that the map of prevalence of the trait almost precisely matched the map of incidence of malaria. Malaria was selecting for the sickle-cell trait. By no coincidence at all, further studies showed that the sickle-cell trait also showed up heavily in locations in Greece and in southern India where malaria was common -- in unrelated populations. The sickle-cell defect is highly distinctive, caused by a specific single-point mutation, which by inference arose in at least three widely-separated human populations independently. Some believe it may have arisen several more times, since the distribution of the defect in Africa covers several distinct populations.
* Malaria has had other impacts on the human species. Humans produce an enzyme with the designation "G6PD" that is involved in the metabolism of glucose in cells. It is a very common culprit in human enzyme deficiencies, with the deficiency due to one or more of 34 possible mutations. A deficiency of G6PD seems to confer marginally higher resistance to malaria -- and to no surprise, the map of high incidence of G6PD deficiency closely follows the map of high prevalence of malaria. In a particularly interesting study, estimates of the age of G6PD gene mutations shows they took place about 3,200 to 7,700 years ago. This is about the time agriculture became common in human cultures, meaning settlements and cleared fields near sources of water -- and much more exposure to mosquitoes that carried malaria.
Humans have acquired evolutionary adaptations to fight malaria -- and in recent times, tried to fight back more actively, eradicating mosquitoes with pesticides and introducing drugs like chloroquine. However, mosquitoes breed rapidly in large numbers and so have quickly evolved resistance to both pesticides and chloroquine, as well as other drugs. Having become sadder but wiser about the inevitability of the evolution of drug resistance in mosquitoes, now the practice is to administer combinations or "cocktails" of drugs. The odds of a mosquito obtaining a mutation to deal with one drug are pretty good; the odds of a mosquito obtaining two simultaneous mutations to deal with two drugs are very low.
Our knowledge of evolutionary science and genetic modification also gives us a Zen approach to fighting back: genetically engineer mosquitoes to resist infection by the plasmodium parasite that causes malaria. Since mosquitoes are such a nuisance it seems a bit perverse to try to improve on them -- but if we must be bitten by mosquitoes, we might as well make sure they don't make us sick in the bargain as well. [TO BE CONTINUED]START | PREV | NEXT
* INFRASTRUCTURE -- ROADS (3): Early roads were just dirt tracks, which tended to become rutted and in particular muddy. The obvious thing to do was to pave the roads, using stone blocks or tiles, but it was hard to get a smooth roadway with that approach, and harder still to keep it smooth -- frosts would heave up the blocks, people would steal them, and so on. Trying to lay down the stones in beds of sand to help keep the road level didn't work.
It took a long time to come up with a better roadway. The major breakthrough was established by a British engineer named John Loudon McAdam, who decided that the best road would use a layer of crushed gravel compacted on the roadbed. It was the use of crushed stone that was the innovation: the broken stone would compact together in a mass, while rounded natural pebbles could be compacted forever and not become much more coherent. Such "macadamized" roads were very labor-intensive to build, but they were much more useful than any roads built to that time. They became more useful when it was learned that a top layer of tar mixed with the gravel would create a more resilient road, and such "tarmac" roads were the basis for typical modern roads.
Eventually the tar formulation settled on bitumen, or refinery bottoms, with "blacktop" roads featuring a multilayer structure: a base of compacted earth, then a thick later of packed gravel, a rough "base course" of blacktop with heavy aggregate, followed by a "binder course" of smaller aggregate, and finally a "surface course" of small, smooth aggregate. Blacktop tends to flex under pressure, which gives it a certain resilience to damage but also can lead to gradual erosion. Eventually, it will have to be resurfaced, with machinery stripping up the top layer, then remixing it with bitumen and laying it down again -- a neat bit of materials recycling. Incidentally, a type of "porous blacktop" has been introduced for use in parking lots; it allows water to seep right through, simplifying drainage.
Blacktop tends to wear out quickly under heavy traffic conditions, and so high-density sections of freeways are often made of concrete slabs, laid down on a bed of compressed earth and a thick layer of gravel. To compensate for thermal expansion, there are usually periodic joints between the slabs -- giving the BUMP-BUMP-BUMP sound of driving down a freeway -- with steel dowels between the slabs making sure they stay aligned and a filling, often of tar, to keep water out of the gaps. Long smooth sections of concrete roadway are built by providing them with a matrix of steel reinforcement.
The key to the modern road is the pneumatic tire. Given the speed and density of modern traffic, there's no way a road could hold up if it were traveled by rigid tires. The pneumatic tire not only provides a smoother ride, it ensures that the road doesn't have to be replaced every year. [TO BE CONTINUED]START | PREV | NEXT
* GROWING THE WEED: In the latest news from the "lateral thinking" department, THE ECONOMIST reports ("On A High", 23 Jun 2007) there is agitation among the US agriculture community to start growing hemp in a big way. The immediate reaction to this idea is that some folks have been smoking funny cigarettes and want to expand on the habit, but hemp has plenty of uses besides as an intoxicant. The article cited a 1942 film released by the US Department of Agriculture titled HEMP FOR VICTORY: "Hemp for mooring ships! Hemp for tow lines! Hemp for tackle and gear!" Hemp was an excellent material for fabricating parachute lines.
Alas, hemp production never took off in the USA. Restrictive laws had been passed against growing the plant in 1937; they weren't enforced during the war, but in the 1950s the authorities began to take them seriously, and shut down hemp production. The only way to grow hemp commercially in the USA nowdays is with a permit from the Drug Enforcement Agency (DEA), which takes a dim view of issuing such authorizations. Hemp products -- rope, food, lotions, clothing, paper, and so on -- are still commonly sold in America, but they have to be imported from China or Canada. In fact, industrial-grade hemp isn't a very good intoxicant. It's a plant with many practical uses -- it is even a potential biofuel feedstock -- and the term "weed" is only too appropriate, since it grows easily, anywhere, with a minimum of tending.
In 1999, South Dakota passed laws to encourage farmers in the state to grow hemp, though they still had to deal with the DEA roadblock. Two farmers from South Dakota have now begun a lawsuit to press the DEA to start issuing permits. Bills relaxing the laws against hemp cultivation are also working their way through the US Congress. Not even the wildest stoner from the 1960s could have imagined the possibility that in the 21st century we might be fueling our cars on mojo weed.BACK_TO_TOP
* DNA ANALYSIS FOR CONSERVATION: Back in March 2006, an article in these pages discussed the use of DNA analysis of pets in forensic analysis. As reported in an article in THE ECONOMIST ("Conservation A La Carte", 3 March 2007), DNA analysis of animals has other uses as well.
About a decade ago, a team of Canadian researchers bought up seal penises from shops in the Far East, where a powder made from the organ is prized as an aphrodisiac. As it turned out, only about two-thirds of the samples were from seals, the others being from cattle, water buffalos, and so on. Similar investigations have shown that turtle meat sold in Louisiana often turns out to be alligator, while in Florida restaurants catfish and tilapia are sometimes pawned off as grouper and snapper.
That's amusing, but such work has a more serious side as well, with the Canadian team also discovering that some of their samples were from protected Australian fur seals and not legally hunted species. As it turns out, DNA analysis is a powerful tool for wildlife conservation.
For a prominent example, Samuel Wasser of the University of Washington in Seattle and his colleagues, working with an Interpol contact, managed to trace a shipment of illegal elephant ivory back to a particular Zambiam game reserve. He obtained DNA samples from elephant dung, which contains cells from the animals' intestinal linings, and built a geographic map to match DNA patterns to regional location. He then extracted DNA from the dead cells on the outer lining of the 37 tusks that had been seized -- developing extraction techniques involving cooling a sample in liquid nitrogen and agitating it to break it up. Other researchers are performing analysis of samples from sharks that uses a particular DNA signature to determine what species the shark is. Work continues into further DNA techniques to help protect other endangered species around the globe.BACK_TO_TOP
* WELCOME BACK TO YOUR SECOND LIFE: An article here back in December 2006 discussed the Second Life online virtual environment, observing that businesses had obtained "properties" in Second Life for promotional purposes. According to an article on the MIT TECHNOLOGY REVIEW website ("A Second Life For Big Business" by Lori Kremen), businesses have other motives for their interest in virtual reality.
IBM, for example, recently bought up ten islands in Second Life. According to Ian Hughes, IBM's "evangelist" for Second Life: "Of course, we hope to attract early adopters, but mostly, these islands are for fellow IBM employees." Second Life provides a chat system that employees can use for virtual conferences, reducing the need for travel. It also provides a medium for socializing between IBM employees. According to Hughes: "It's like what golf used to be."
Most of the IBM islands were built by company employees, though some work was contracted out to professional Second Life architects, one of the best-known being Aimee Weber. IBM hasn't ignored Second Life as a promotional medium, either setting up a "virtual store" in collaboration with Circuit City where visitors can inspect virtual models of IBM products. They can click on a product to take them to the Circuit City web page for purchase. The store is usually virtually manned by a few IBM customer-service representatives, who can answer customer questions.
Internet hardware maker Cisco Systems also bought islands from Second Life for employee and customer use. The Cisco islands include an amphitheater for meetings, and even provide training classes for the public. The main goal of the Cisco presence in Second Life is to provide presales consulting to customers and then provide technical support after the sale.
As discussed in the previous article, old-time Second Life users are a bit uneasy about the presence of corporate entities on their turf, and Linden Labs, which runs the virtual world, has tried to treat corporations just like any other customer. However, Cisco officials are now trying to form a council of corporations running operations on Second Life to discuss security issues with Linden Labs; the corporations seem to be serious about the matter.BACK_TO_TOP
* THE MAKING OF THE FITTEST (14): Having considered convergent evolution at the molecular level, it's worthwhile to take a closer look and see just how plausible the notion of, say, the complete reinvention of trichrome vision really is.
In modern evolutionary theory, the basic assumption is that mutations arise more or less at random (some mutations are more likely than others), and that those mutations that provide a survival advantage are carried on through natural selection. That obviously requires a good deal of time.
Consider the probability of a specific single-point mutation for any base in an opsin gene. The mutation rate is about one per 500 million bases in the DNA of most animals -- or in other words, one in every 500 million offspring will have mutated base of interest. Since there are two copies of a specific gene, that means the odds of getting the mutation are actually twice as good -- two shots per offspring -- and that cuts the odds down to one in 250 million offspring. However, since there's four different bases -- A, C, T, G -- there's three different possible single-point mutations, and since we are after a specific mutation, the odds go up to one mutation per 750 million offspring.
That sounds like wild chance, but given that it's easy to imagine a species with at least a million members -- we humans are far more numerous than that, and we're relatively big animals -- that means that for a species that produces a million offspring a year, a specific single-point mutation happens every 750 years. On an evolutionary timescale, that's a tick of the clock. Of course, there are all other kinds of mutations taking place in the meantime, but many of them are useless and go nowhere, though some improve the fitness of the organism in other ways and are encouraged by natural selection. There is also the time interval for a favorable mutation to propagate through the population, but as noted in a previous installment this is a factor of the selective advantage of the mutation and the population size; the time is also short on the geological scale.
The fitness peak for the spectral tuning of longwave and midwave opsins is fairly tight, there doesn't seem to be many patterns of mutations that can achieve it, but it's far from impossible for the pattern to be duplicated through the processes of random chance. The evolution of opsins requires highly specific changes, but as shown in previous installments, other genetic changes aren't so fussy. In particular, there are many possible ways to break a gene, and so if the gene is not being used, it gets broken pretty quickly, to be passed on without being weeded out by natural selection. Use it or lose it. [TO BE CONTINUED]START | PREV | NEXT
* INFRASTRUCTURE -- ROADS (2): Roads often cross each other, and so considerable effort has been put into designing means to direct traffic through such intersections. The most obvious means, for local and municipal roads, is a two-way or four-way stop, controlled by stop signs. Four-way stops can be a bit confusing at times, so these days there's an increasing tendency to use traffic circles or "roundabouts", in which everyone simply turns right (in the US at least) and goes around the circle to find the appropriate exit. Vehicles in the roundabout have right-of-way.
Roundabouts were unpopular in the US and Canada for a long time, mostly because they had been used early in the 20th century with the rules being that vehicles entering the roundabout had right of way, with the vehicles in the roundabout being forced to stop. It's hard to visualize how that could have ever been sensible. After the modern roundabout caught on in Europe, it finally migrated back to North America. The next step up is to provide traffic lights, with dividers to channel traffic and turn lanes to prevent turning vehicles from blocking traffic.
Multilane roads and freeways usually involve overpasses and underpasses to allow traffic to flow on both roadways without stops. The mechanisms for changing roadways fall into three categories: diamond, cloverleaf, and directional interchanges.
The diamond interchange is the simplest concept and well-suited for transfers between a busy freeway and a light-traffic secondary road. To get off the freeway, the driver simply turns right onto a diagonal exit ramp and drives up to the secondary road, generally being halted by a turn signal. To get back on the freeway, traffic turns right or left from the secondary road, usually at a light, onto a diagonal in-ramp.
A cloverleaf interchange is used to match up two freeways or the like. The driver goes past the alternate roadway on the overpass / underpass and then turns right, arcing around 270 degrees to merge smoothly into traffic. A cloverleaf is more expensive to build than a diamond interchange. A driver also has to slow down significantly to handle the curving ramp, and the crossing of traffic between an in-ramp and out-ramp can be a bit dicey on occasion.
A directional interchange simply uses a set of interchange overpasses or underpasses to link traffic between major freeways. Directional interchanges are very expensive to build but are easy to negotiate, in fact sometimes reminiscent of a theme-park ride in which the rider flies over bridges and down tunnels. The only real problem with them from a driver's point of view is that it's usually difficult to correct the error of taking the wrong exit, the vehicle being trapped in the output freeway until the driver can find another exit to turn around. [TO BE CONTINUED]START | PREV | NEXT
* DAMN LIES & STATISICS: Anyone who follows medical research can be forgiven if the results cited in research papers sometimes seem a bit less than persuasive, since the statistics cited are prone to a wide range of sources of error. As reported in an article in THE ECONOMIST ("Signs Of The Times", 24 February 2007), such doubts have been increased by a study performed by Dr. Peter Austin of the Institute for Clinical Evaluative Studies in Toronto, Ontario, Canada, in which he correlated records of hospital admissions to the astrological sign of the patients. The results were intriguing: Leos are 15% more likely to suffer from gastric bleeding than those born under the other 11 signs, while Sagitarrians are 28% to suffer a broken arm. Of course, Austin wasn't serious, but his study was more than mere prank: he wanted to show the risks of basing medical studies on weak statistical methods.
The main issue that he was aiming at was the practice of testing multiple hypotheses in the same analysis -- in this case, testing 24 hypotheses, two for each astrological sign. The result of such agglomeration is that some results will vary by sheer chance from the others and produce a "false positive". If each hypothesis was instead given its own analysis, the significance of the result would be lost in the noise.
Austin was not simply trumping up a case. John Ioannidis of the University of Ioannina School of Medicine in Greece earlier pointed to six well-known medical studies that proved unduplicable in five cases. He claimed that studies were generally so sloppy that their results could only be regarded as solid about a fifth of the time. Worse, he believes that studies that test multiple hypothesis at the same time may be valid as little as a thousandth of the time. Medical studies are highly prone to confounding factors and it can be very hard to pick a signal out of the noise; now we're getting data that shows it is even harder to do than we used to think.
ED: This article reflects on the odd inclination that people have of citing a research paper published in a formal research journal as "proof". Actually, any one paper constitutes proof of very little. A research paper merely presents the results of the experiments or analyses performed by the authors; the editors of the journal can do little but look over the paper to see that it's not obvious junk, since they're not in a position to validate its results. The published paper then gets feedback from the relevant research community. The results of a single paper only become significant when they're backed up by several more papers from different sources.BACK_TO_TOP
* PHONE MONEY HOME: According to a BBC WORLD Online article ("Migrant Workers Gain Mobile Banks"), the increasing use of cellphones for financial transactions is now linking up with the enthusiastic use of cellphones in developing nations -- in schemes to transfer money from migrant workers back home to relatives. The International Monetary Fund estimated that in 2005 transferring the equivalent of $200 USD back to relatives in the countryside could cost about 10% of the sum transferred -- a serious bite to anyone, and a major blow to people who don't have much money to begin with. It is obvious that such transactions could be handled more efficiently, and that any system that did so would become popular quickly.
One pilot program, M-PESA, has now been set up as a joint venture between UK cellphone giant Vodafone and Kenyan mobile phone operator Safaricom, with backing from the British government's Department for International Development. Initially, it's only operating within Kenya, but it will gradually be extended beyond the country's borders. Most users don't have bank accounts, but they can deposit and withdraw funds from the M-PESA system through Safaricom shops, filling stations, or other commercial outlets. M-PESA stores the money as a single account in the Commercial Bank of Nairobi. The Kenyan Central Bank approves of the arrangement, as long as M-PESA doesn't pay interest or try to make interest on the account.
M-PESA was begun in March 2007 and within a few months had 150,000 users, as well as 500 outlets. Says the Kenyan minister of communications, Mutahi Kagwe: "This will help people in far-flung parts of the country who have no banking services. Now anyone can have a bank in their pocket."
A broader effort is being coordinated under the umbrella of the GSM Association, with 19 member companies (including Vodafone) working together to come up with a common system that would span the globe. In full operation, the system will offer several different money transfer schemes, but as a common theme they will provide "virtual vouchers" that can be traded in for cash. The person sending the money can do so through the internet or a cellphone, accessing a local bank account through user software. The recipient will simply need a phone with a short messaging service (SMS) capability, with the payment arriving in the form of a text message with a secure ID code. As with M-PESA, the message could be taken to a variety of outlets, with the default being retail outlets now selling cellphone airtime. Mobile networks now cover 80% of the Earth's land and there is a network of retailers to support them. Controls are being considered to deal with money laundering.
The World Bank estimates that the global remittance market now runs to the equivalent of $268 billion USD, and in some poor countries remittances account to a third of a country's GDP. The GSMA believes that by 2012, given implementation proposed schemes, the number of people performing remittances could double to about 1.5 billion, with the money flow quadrupling to about $1 trillion USD.
India has the world's fastest growing mobile services market and is also the biggest recipient of overseas remittances, accounting for around 10% of the world market. India's largest bank, the State Bank of India, is one of the key partners in the GSMA project. Says bank chairman O.P. Bhat: "We piloted a project in a small Himalayan village of Pithoragarh in India with Airtel and have seen the tremendous results in this unbanked village. This project has the potential of transforming the lives and economies across the globe."BACK_TO_TOP
* CARBON NANONETS: As discussed in an article from SCIENTIFIC AMERICAN ("Carbon Nanonets Spark New Electronics" by George Gruner, May 2007) in the 1990s, chemists learned the trick of rolling up the hexagonal grid of carbon atoms known as "graphite" into tiny balls and tubes. It was an impressive accomplishment, though at the outset the reaction was sometimes along the line of: "Cute, but what good is it?" Those working in the field understood perfectly well that it takes time to exploit a major technical breakthrough, and believed that such a leap in technology was going to have a wide range of applications.
Applications are now starting to emerge. Carbon "nanotubes" seem to have a particularly promising future in electronics. Chemists can tweak them to act as conductors, just like copper threads, or semiconductors, like silicon. Fabrication of carbon nanotube devices also appears to be straightforward: a solution of the tubes can be sprayed on various substrates, including plastic to form a nanotube layer, and additional layers can be applied over the base layer to provide electronic functions, such as emitting light. While nobody expects to make a quad-core computer processor chip with carbon nanotube technology any time soon, it does seem well-suited to applications such as "electronic paper" for roll-up displays; chemical sensors; wearable electronic devices fabricated into clothing; solar power cells printed onto rooftop tiles; or radio-frequency identification (RFID) devices. These would be relatively uncomplicated, built using cheap, flexible, lightweight, and (when needed) transparent electronic circuitry.
* Carbon nanotubes were actually discovered several decades ago, but nobody paid any attention. In 1991 Sumio Ijima, a chemist at Nippon Electric Corporation (NEC) in Japan, rediscovered them and realized their potential. Carbon nanotubes can have conductivities comparable to copper and current densities (maximum current capability per unit of cross section) a hundred times better. The nanotubes are also physically robust, capable of being bent without damage and relatively inert chemically.
Carbon nanotubes are fabricated by vaporizing coal with an electric arc or a laser, and then using a catalytic process to convert this "carbon plume" into various sorts of carbon molecules that amount to soot. This soot includes various forms of spherical graphite assemblages, known as "buckyballs" or "fullerenes" after inventor R. Buckminster Fuller, and carbon nanotubes -- sometimes with single tube walls, in some case with multiple concentric tube walls. Sorting out this mix is troublesome and so carbon nanotubes are currently very expensive, but given a mass production application there will be an incentive to scale up carbon nanotube manufacture to an industrial process.
Prototype carbon nanotube transistors are actually as fast as or faster than silicon transistors, but they can be very difficult to make, and don't have uniform properties because of variations in nanotube configuration. One way to get around the variations is to lay down a thin film layer of carbon nanotubes. The conductivity of this "nanonet" is much more predictable, since it's an average of the nanotubes that make it up, providing conductive paths from one side of the nanonet to the other. If some of the nanotubes are broken, the others easily take up the load. The nanonet is so thin and sparse in its coverage that its transparency can easily exceed 99%. It is also flexible and resists damage from physical shocks.
* Laying down a carbon nanonet isn't trivial, and early efforts to do so left much to be desired. The idea of simply dissolving the nanotubes in alcohol or some other solvent and then spraying them on didn't work very well in practice, since the nanotubes tended to clump together. Adding surfactants -- soaps -- helped keep the tubes apart by coating the tubes with a non-stick layer; however, once sprayed on the surfactants tended to interfere with the operation of the nanolayer. Several years of tinkering with combinations of solvents, surfactants, and processing technologies has finally led to the ability to produce workable nanonets on substrates at near room temperatures. The transparency of the nanonet can be controlled by adjusting the thinness of the layer.
The first nanotube-based field-effect transistors were built in 2003, though they required high temperatures that ruled out plastic substrates. Transistors on flexible plastic substrates followed quickly, followed by transparent devices useful for displays. These devices required relatively high voltages for operation, making them unsuitable for battery-operated systems, but low-voltage devices have now been fabricated.
Considerable research is being performed on solar power cells incorporating nanotube electrode layers sandwiching a photovoltaic material layer made of polymers or other flexible materials. Such devices have low efficiencies, only about 6% at most, but they are potentially very cheap and could be fabricated on a wide variety of substrates, such as roofing tiles. Other devices being investigated include touchscreen overlays for displays, consisting of two transparent conductive nanotube layers separated by insulating spacers; and batteries or other power technologies. Devices will be made by inkjet or offset printing technologies. Right now, carbon nanotube technology is where silicon transistors were in the 1950s. Progress in the field is proving rapid, and carbon nanotubes appear poised to take off.BACK_TO_TOP
* THE MAKING OF THE FITTEST (13): It was noted in an earlier installment in this series that no New Wold monkeys are trichromats, with one exception. That exception is the howler monkey, noted for its oversized voicebox, which gives it the ability to produce really loud calls. It is also, unusual among New World Monkeys, a leaf-eater, and so it's not too surprising that it's a trichromat, with genes for longwave, midwave, and shortwave opsins.
Since the Old World monkeys have trichromat vision and all the other New World monkeys don't, the question comes up as to whether the howler monkey "reinvented" trichrome vision, or if the other Old World monkeys also had trichrome vision early on and lost it. The answer is that the howler monkey "reinvented" it.
First, there's no broken gene for a third opsin in the Old World monkeys. Second, the duplicated opsin genes that produced trichrome vision in Old World monkeys are clearly distinct from the duplicated opsin genes that produced trichrome vision in the howler monkey. The longwave and midwave opsins in all Old World monkeys both carry a chunk of "junk DNA" 236 base pairs long. Both obtained that distinctive chunk of junk DNA from their long-midwave ancestor. The longwave and midwave opsins of the howler monkey also both carry a chunk of similar junk DNA, but it's much longer.
Furthermore, due to genetic drift, the longer ago the two opsin genes were produced, the more they will differ. The two opsin genes in Old World monkeys are about 5% different, while the two opsin genes in the howler monkey are about 2.7% different. The implication is that the gene duplication event in the howler monkey was much more recent.
What is particularly astonishing about the howler monkey's "reinvention" of trichrome vision is that the howler's longwave and midwave opsins are tuned to exactly the same color bands as those of Old World monkeys, using very much the same critical mutations. This is "convergent evolution" at work: the specific color bands were "optimum" in terms of selective advantage, and there was no other available set of mutations that could produce them.
* It is possible to describe other interesting examples of convergent evolution at the genetic level. For instance, there are dozens of different populations of the Mexican blind cave fish. As cave fish often are, they are all albinos: their coloration genes broke and weren't missed. Genetic investigation of the same pigment gene in multiple Mexican blind cave fish populations indeed showed that the gene was broken in all of them -- but it was broken in a different way in each of the different populations. Each population became albinos independently.
It was mentioned in an earlier installment that the icefish and its relatives of Antarctic regions have an "antifreeze" in their blood consisting of a simple protein sequence. There are Arctic fish species that have an antifreeze consisting of a simple protein segment in their blood as well. The two groups of fish are not closely related, and it turns out the construction and genetic coding of their antifreeze components is entirely different. They are only functionally similar; unlike the tuning of opsins, there were multiple paths to obtain the equivalent adaptation.
There are also genetic examples of "divergent evolution", or different solutions to the same problem. Venoms known as "potassium channel blockers" that paralyze the nervous system are found in some snakes, sea anemones, sea cone shells, and scorpions. All four venoms work in much the same way, but they have entirely different protein sequences and genetic coding. Divergent evolution has produced entirely different but functionally similar solutions to do the job. [TO BE CONTINUED]START | PREV | NEXT
* INFRASTRUCTURE -- ROADS (1): Chapter 8 of Brian Hayes' book INFRASTRUCTURE covers roads and highways. The modern global road network is impressive; someone brought from a century past, when the automobile was still just a rich person's toy, would find the level of resources invested into it astounding.
Roads of a sort have been around for about as long as wheeled transport has been around, possibly before, starting out as mere widenings of footpaths. Of course, that led to improving the roads, by the simple measures of leveling them, carpeting them with stones, or "corduroying" them with trees and branches. The Romans, being excellent engineers, built proper roads with an underlying bed, the roads being paved with stones and featuring drainage systems.
In colonial days, roads were built to connect cities and to allow access to the frontiers. A National Road project was started by the US Congress in 1806, the original plan being to span the Appalachians, with ambitions gradually expanding to reach Saint Louis, Missouri. It had reached Illinois when it was canceled in the 1840s. Canals and then the new railroads were taking over long-distance transport, and long-distance roads fell into decline for the rest of the century. The invention of the automobile in the next century revived them, the first manifestation being the "parkways" built before and after World War I. These introduced the basic features of modern freeways: four lanes, split by a median, with overpasses and access ramps. Such old parkways are still much in evidence in the New York City Metro area.
Interstate connections were more primitive in those days. Highway-building in the 1920s and 1930s resulted in the national Lincoln Highway, the Ocean-to-Ocean Highway, and shorter routes, but these roadways were unimpressive by modern standards, being usually only two lanes and broken by stops. Hitler's Germany built the Autobahn, a pioneer in design of the modern freeway system. Legend has it that the Autobahn was built primarily to support military transport, but it wasn't really laid out for heavy vehicles, and trains were used to move soldiers and combat equipment instead. The US Federal government committed to the interstate highway system in the 1950s, with the core network completed in the early 1960s. In principle, it allowed a driver to reach any major city in the USA without ever being forced to stop, except to rest and gas up.
The US interstate system now spans a total of over 70,000 kilometers (45,000 miles). There is a pattern to the way the interstates are numbered. Major routes have numbers less than 100, with east-west routes ending in a 0 and north-south routes ending in a 5. The numbering increases south to north, west to east: I-5 runs up the Pacific coast, I-95 the Atlantic coast, I-90 across the northern US, I-10 across the south. Numbers higher than 100 are for spurs, loops, and connectors -- the well-known Washington DC "beltway" is I-495. The designation scheme isn't completely consistent, featuring a number of exceptions.
* Layout of a road or freeway involves initial consideration of the sharpness of curves and the steepness of grades. In the USA, curves are measured by the change in direction in degrees over 30 meters (100 feet) down the centerline of the road; a 5-degree curve changes direction by 5 degrees in 30 meters. The maximum curvature of an ordinary road is no more than 7 degrees, usually more like 5 degrees; for high-speed roadways, it's no more than 3 degrees. Grade is, of course, just the rise divided by the run: a 12 meter rise in 100 meters is a 12% grade. For a design speed of about 50 KPH (30 MPH), the maximum grade is 12%; for a high-speed route it's 5%, since large vehicles can't maintain speed on steeper grades.
Highway engineers also work using a large number of rules of thumb intended to make life easier for drivers. Long straight sections of road should be connected by long shallow curves, not short sharp ones. A continuous curve in a single direction should not include a straight section in the middle, though it's a good thing to do with an "S" curve. It's regarded as a good idea to begin curves at the top of a hill or in the bottom ("sag") of a valley, though hilltop crests can't be too sharp lest they surprise drivers, particularly at night. Long straightaways are preferred near intersections so drivers can see crossing traffic.
Older highways tended to be laid out in straight lines wherever possible. This was easy to plan and made passing on two-lane blacktop safer. However, it also made for a more hypnotic ride, and more modern highways tend to be designed as long, shallow, winding curves. [TO BE CONTINUED]START | PREV | NEXT
* NORTH KOREA GOES WIRED: When one gets over, at least for short periods, being appalled and terrified of North Korea, the place does provide a bit of surreal humor. According to an article in THE ECONOMIST ("Weird But Wired", 3 February 2007), North Korean dictator Kim Jong-Il is a believer in the power of computer networking. Despite the poverty of the country, second-hand PCs are common in schools, where kids can be seen playing computer games, and young adults arrange dates.
North Korea set up a national intranet using fiber-optic links in 2000, and the country's first cyber-cafe was opened in Pyongyang in 2002. They are now common throughout the country. The national intranet is supported by a custom browser and email utility at the local end, and news groups and a search engine downstream in the servers. North Korean business cards now usually include an email address, though it's almost always for an organization, not an individual.
Although China spends a lot of effort screening access of citizens to the outside internet, that isn't a problem for North Korea -- because the citizenry isn't allowed to browse outside the country in the first place. The news system is controlled by the state news agency, KNCA, relying heavily on the thoughts of the Great Leader Kim Jong-Il, while being selective and sketchy on factual reportage. A qualified group is permitted to browse abroad to track down useful materials for translation and addition to the North Korean system.
Citizens realize they are being watched and are careful about what they say online, with reports of police crackdowns last summer on net cafes that crossed the bounds. However, even in North Korean the computer communications revolution is not proving 100% controllable. Up in the border region with China, North Korean citizens have been getting their hands on Chinese cellphones and prepaid cards, with web-enabled phones allowing the people to get a look at the rest of the world. Chinese access to the global web is notoriously constrained, but compared to the complete isolation of the North Korean intranet, the freedom must be breathtaking. However, that doesn't necessarily equate to political expression as such: gambling is popular in the border region and it seems online gambling has become popular there.BACK_TO_TOP
* VACCINES FOR JUNKIES: According to an article from MIT TECHNOLOGY REVIEW ("Vaccines For Addictions" by Emily Singer), biomedical researchers are now working on vaccines to neutralize the effects of recreational drugs in the bloodstream. It sounds like a wild idea, but it's perfectly logical. One of the arms of the immune system are the proteins known as "antibodies": once the body recognizes a particular invader, such as a toxic molecule, it starts generating antibodies matched to that invader, which bind to it and neutralize it. A team under Thomas Kosten, director of the division of alcohol and addictive disorders at Baylor College of Medicine in Houston, Texas, has just completed two clinical trials, one for a vaccine against nicotine and another for a vaccine against cocaine, with results expected soon.
Molecules of cocaine, methamphetamine, nicotine, and other drugs occur in concentrations too low to trigger an immune response. The vaccines bind groups that mimic the target drug to larger proteins, forcing an immune response. When a subject that has been vaccinated tries to the use the drug, antibodies bind to it and blunt the effect.
A nicotine vaccine is almost ready for widespread use, with clinical trials demonstrating that it is effective, if not a perfect cure by any means, with the relapse rate still unknown. Work on vaccines against cocaine, methamphetamine, and PCP has not been moving rapidly due to lack of funding. Says Kosten: "The cocaine vaccine has been almost entirely supported by NIDA [the US National Institute of Drug Abuse]." So far, commercial pharmaceutical companies haven't shown much interest.
Current vaccines in trials have some limitations. Not everyone produces enough antibody to block a drug, and a determined addict can still get high by upping the dose. Some researchers are synthesizing antibodies from animals and then injecting the most powerful into subjects, a scheme called "passive vaccination". Michael Owens, a pyschopharmacologist at the University of Arkansas for Medical Sciences in Little Rock, is working on passive vaccines for methamphetamine and PCP, and has created a start-up company, Intervexion Therapeutics, to commercialize the drug.
Passive vaccines are expensive, but the methamphetamine vaccine can also bind to amphetamines and ecstasy. In addition, it could help deal with overdoses by neutralizing drugs in the bloodstream. Even the optimistic think it will be several years before such vaccines are available, but they remain upbeat about their potential.BACK_TO_TOP
* FUELS FROM ALGAE: Research into the production of "biofuels" has been moving in a number of different directions. As reported in an article on the MIT TECHNOLOGY REVIEW website ("Algae-Based Fuels Set To Bloom" by Kevin Bullis), one of the more interesting new approaches to producing biofuels is to use pond scum -- the little green aquatic plants more formally known as "algae".
A number of startups are now tinkering with the idea. Algae makes oil naturally, and the plants can be processed into biodiesel and other hydrocarbon products in much the same way as soybeans or oilseeds. A somewhat more interesting approach is to grow strains of algae that produce more carbohydrates and less oil, with the algae then run through a fermentation process to yield ethanol; the waste from the process can be used for animal feed. Algae can be grown in open ponds or in sealed clear tubes, and can produce much more oil per hectare than soybeans. The algae can also soak up carbon dioxide and nitrous-oxide pollutants produced by powerplants.
The idea of algae-based biofuels is not new. The US National Renewable Energy Laboratory (NREL) in Golden, Colorado, ran a study for almost a decade, with the work ended in 1996. At the time, ordinary petroleum was too cheap to make the idea competitive. NREL now hopes to restart the program in the near future, though an NREL researcher warns that "you have to be careful because there's a lot of hype out there right now."
Better understanding of the biology of algae could help. Algae will produce up to 60% of their weight in oil, but only when they're starved for critical nutrients, and then they stop reproducing rapidly. A modified algae that produced a high proportion of oil but still replicated rapidly would be an excellent biofuel source. Other difficulties include the issue of keeping ponds of algae free of other organisms. There's also the issue of cost: the economics of biofuels in general will look much better if governments implemented a "carbon tax", giving an advantage to fuel sources that do not increase net carbon-dioxide emissions.
Some of the startups believe they can still produce a cost-competitive product even without a carbon tax, but that means overcoming a number of technical obstacles. Says Lissa Morgenthaler of LiveFuels, one of the companies working on algae-based biofuels: "Clearly, it can be done. The only question is whether we can do it cheaply. And the only way we're going to find that out is if we do it -- if we actually go out, crank it through, spend some millions on it, and make it happen."
* In related news, THE ECONOMIST reviewed the possibilities of using trees to produce cellulosic ethanol. In the USA, much of the focus on cellulosic ethanol feedstocks has been on prairie grasses, but obviously that isn't an option in lands that don't have much in the way of prairies. In countries where forests are widespread -- Sweden and New Zealand, for example -- there's a lot of interest in using trees as a feedstock. New Zealanders are enthusiastic about willows, since they grow well in poor soil not otherwise useful for agriculture, and in fact a pilot plant is being built there to produce willow ethanol. Factoring in byproducts from the process, the ethanol from the pilot plant should be competitive with ethanol from other sources. The Swedes are more interested in poplars, which grow well in Sweden.
There is the problem that trees tend to grow slowly, but work is being performed on obtaining fast-growing trees -- either by selective breeding or genetic modification. One of the limiting factors in the growth of trees is the level of lignin, a tough material that helps maintain plant structure. As it turns out, getting rid of lignin is one of the obstacles in producing ethanol from trees. A fast-growing tree would have less lignin, making it doubly attractive.
* MIT TECHNOLOGY REVIEW Online also interviewed a British Petroleum (BP) official who promoted BP's interest in producing butanol instead of ethanol. Ethanol has a number of well-known limitations: it has about two-thirds the energy density of gasoline, meaning a tank of ethanol won't take a car as far as a tank of gasoline; it's a solvent and cars that pure ethanol require special fittings; and it can't be pumped through ordinary gasoline pipelines. Butanol can be made from the same feedstocks -- corn, sugar cane, or sugar beets -- but it has better energy density (almost 90% of gasoline), doesn't require special fittings, and can be pumped through gasoline pipelines. BP recently funded a ten-year program at the University of California, Berkeley to the tune of $500 million USD to advance biofuel technology, with an emphasis on butanol, and in 2006 BP set up a partnership with US chemical giant DuPont to develop new butanol production processes.
Another comment from MIT TECHNOLOGY REVIEW Online discussed synthesizing propane instead of ethanol from corn or sugarcane. Propane is used in the USA for residential heating, some industrial processes, and as a transportation fuel -- fork lifts are often run on propane and it is commonly used to fuel road vehicles in some places, such as Australia. The total American market for propane is $21 billion USD a year. Propane is gaseous under normal conditions, but can easily be liquefied at modest pressures; it has a higher energy density than ethanol and burns very clean. However, a standard automotive engine cannot burn propane without modification. The synthesis process for propane requires less energy input than the synthesis of ethanol.BACK_TO_TOP
* ANIMAL TROUBLE: With reports of continuing problems on the International Space Station (ISS), it comes as no surprise that the one true source of news, THE ONION, reports that the station is having varmint problems in the form of a pesky raccoon that has taken up residence there. ISS Science Officer Mike Fincke said via a video-link to Russian mission control: "Yesterday, we found fruit rinds in the EVA suits and helmets, and the day before, it was garbage strewn all over the Pirs Docking Module. Today, a controller on the starboard truss failed because the power cord was chewed clean through. The little guy's curious, that's for sure."
Both Fincke and Expedition 9 Commander Gennady Padalka of Russia reported surprise run-ins with the raccoon. Fincke said he traced the recent contamination of the ISS water supply back to the raccoon's habit of washing its food before eating it. The American astronaut added that the space station's external-refuse cylinders are regularly turned over and rummaged through -- especially on nights when the crewmembers have consumed fish dinners or freeze-dried "astronaut ice cream."
Neither of the two spacefarers has been able to outsmart the resourceful animal, despite weeks of effort. Says Padalka, who has been appointed temporary pest-control officer for the ISS: "We've put out live-capture traps, but the little bandit somehow always makes off with the bait. Evidently, due to zero gravity, the raccoon does not weigh enough to depress the trigger plate."
While capturing the animal remains a top priority, Expedition 9 crewmembers are determined not to harm their guest. According to Fincke: "Heck, if we announced we were going to exterminate him, mission control would go berserk. They can't get enough of his tricks."
According to Padalka, the little critter's mischief does provide the crew with much-needed entertainment. When Padalka opened his locker last week and found an orbiting thundercloud of rumpled wrappers in place of his private supply of Snickers bars, Fincke laughed so hard he spit out the pouch of water he'd been drinking. However, Fincke was not the one laughing when he spotted the critter running off wearing his spare Orlan-M spacesuit helmet. But both astronauts did enjoy seeing the bewildered raccoon scrambling to keep up with the zero-gravity treadmill, after having apparently triggered its "quick-start" switch.
"You have to give it to the little guy, he's persistent," said Fincke, who, while calibrating the ISS telescope last week, had a rare opportunity to view the raccoon up close, when its masked, bewhiskered face stared back at him through the telescope's other end.
Although NASA has been unable to determine how the animal got on board, lab analysis of the beast's droppings suggests that it's the same raccoon that raised hell on the ISS during Expedition 7 in 2003. While none of the previous crew's members would admit to feeding the raccoon -- which would explain its return -- many expressed affection for the animal. "I call raccoon Kosmo-Rascal, after favorite children's book," Expedition 7 Commander Yuri Malenchenko said. "If we caught him, I think we might have used him in benign experiment, maybe about training to do tricks. Is true nobody wants air filter clogged with nutshells, but nobody wants raccoon hurt, either."
ISS personnel agree that, while unexpected, the raccoon has been a good learning experience. As Fincke put it: "This is how astronauts learn to deal with new things -- by living through them. Zero gravity, environmental adaptation, varmints ... all these are unplanned things that surprise us when we take a step into space. But we aboard ISS Expedition 9 haven't met a problem too big for us yet, and we'll work this raccoon thing out sooner or later -- hopefully, before the clever little bandit figures out how to work the airlocks."BACK_TO_TOP