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DayVectors

oct 2009 / last mod nov 2015 / greg goebel

* 22 entries including: parasites, Southwest road trip, Augustine Committee on human spaceflight, Jill Price remembers all, flu frenzy, combined-effect EMP munitions, bug spatters for science, butterfly family tree, self-powered electrical generators, the science of bug stings, and e-waste calamity in China.

banner of the month


[FRI 30 OCT 09] NEWS COMMENTARY FOR OCTOBER 2009
[THU 29 OCT 09] SCIENCE NOTES
[WED 28 OCT 09] REMEMBER EVERYTHING
[TUE 27 OCT 09] MORE FLU FRENZY
[MON 26 OCT 09] SOUTHWEST ROAD TRIP (1)
[FRI 23 OCT 09] THE PARASITES (24)
[THU 22 OCT 09] GIMMICKS & GADGETS
[WED 21 OCT 09] COMBINED-EFFECTS EMP MUNITIONS
[TUE 20 OCT 09] BUG SPATTERS FOR SCIENCE
[MON 19 OCT 09] NEW OPTIONS FOR HUMAN SPACEFLIGHT (4)
[FRI 16 OCT 09] THE PARASITES (23)
[THU 15 OCT 09] SPACE NEWS
[WED 14 OCT 09] SELF-EMPOWERED
[TUE 13 OCT 09] FLU FRENZY
[MON 12 OCT 09] NEW OPTIONS FOR HUMAN SPACEFLIGHT (3)
[FRI 09 OCT 09] THE PARASITES (22)
[THU 08 OCT 09] SCIENCE NOTES
[WED 07 OCT 09] THE STING
[TUE 06 OCT 09] E-WASTE CALAMITY
[MON 05 OCT 09] NEW OPTIONS FOR HUMAN SPACEFLIGHT (2)
[FRI 02 OCT 09] THE PARASITES (21)
[THU 01 OCT 09] ANOTHER MONTH

[FRI 30 OCT 09] NEWS COMMENTARY FOR OCTOBER 2009

* NEWS COMMENTARY FOR OCTOBER 2009: The American war in Afghanistan got off to a good start, but it has since bogged down. US casualties have been increasing in Afghanistan, while concerns over the weak and corrupt Afghan government of President Hamid Karzai have been growing in pace. As THE ECONOMIST pointed out, many have been drawing parallels to the US involvement in Vietnam. As in Vietnam, the Afghan conflict is a protracted war against an enemy that seems impossible to suppress, in support of a feeble friendly government.

The parallels are not completely accurate: the adversary Taliban has no major state backer to support it, the scale of the fighting is far lower, and American public opinion is more ambivalent than hostile. However, the parallels remain, and Obama remains clearly ambivalent himself, still mulling over committing more troops while wondering what America can do about Karzai government to get back on track.

* In the meantime, events back home are also contributing to the president's restless nights. In an event that attracted surprisingly little attention, on 23 September one Michael C. Finton, AKA "Talib Islam", tried to use a cellphone to detonate a van full of explosives outside the Federal courthouse in Springfield, Illinois. The van didn't go off, and no wonder: Finton's supposed al-Qaeda contacts were Federal agents and the van's contents were harmless.

An Afghan legal immigrant named Najibullah Zazi was similarly busted by the Feds for planning attacks in New York City and trying to brew explosives in a Denver hotel. Still other terror attacks have been frustrated; since 911, almost two dozen terrorist attacks on the USA have been foiled, with almost 700 suspects prosecuted and a third of them charged. A third of them were US citizens.

According to THE ECONOMIST, from the legal point of view, the Obama Administration is not finding the terror issue that much easier to deal with than the Bush II Administration did. As discussed here late last year, it was obvious that handling terror suspects and phasing out the detention center in Guantanamo were not trivial matters. Obama has shut down secret detention centers overseas, allowed the Red Cross access to the non-secret ones, and made it clear that Guantanamo will be closed -- though it is somewhat unclear as to when. The delay in turning off "Gitmo" has civil libertarians somewhat worried; they are more worried about the fact that the president has not given up holding suspect terrorists indefinitely without trial. Closing down Gitmo doesn't seem so significant if it just means suspects will be held someplace else.

razor wire at Guantanamo

The problem is that, though many of the suspects were released during the Bush II Administration, about 200 are simply too dangerous to be let go -- but there's not enough evidence to take them to trial, or the evidence that could be used is tainted by the fact it was obtained by rough interrogations, meaning the case would be thrown out of court. There is the option of just biting the bullet and letting them go, but if even one of them then killed some people, the White House would be in serious political hot water and the Obama Administration knows it.

Obama originally asked Congress to help frame a law for handling these suspects, but that approach went nowhere. Now, just like the Bush II Administration, the Obama Administration is relying on the broad authorizations provided by Congress after 911. The disinterest of Congress in dealing with the suspects is not so surprising, there being no really attractive options in the matter, and any good politician knows to avoid a no-win game. Indeed, to the extent that folks in Congress demonstrated much interest in the matter, it was just to make sure the suspects didn't end up in their districts: NOT IN MY BACK YARD! The Obama Administration, in contrast, has to deal with the matter whether there are any good options or not, and in the absence of any help has little choice but to handle matters using the existing rules, inadequate as they are.

President Dwight Eisenhower once observed: "Any man who wants to be president is either an egomaniac or crazy." I tend to be patient with those in authority. I don't necessarily believe they are always doing a good job or that they're even very conscientious -- but given the sheer despairing impossibility of the task, I'm not in a position to tell them how they could do things better.

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[THU 29 OCT 09] SCIENCE NOTES

* SCIENCE NOTES: According to AAAS SCIENCE, the US Geological Survey (USGS) got rave reviews from the Earth science community by posting online almost 1,200 high-resolution images of the Earth's surface obtained from US military reconnaissance satellites. These images have roughly six times better resolution than those available from commercial satellites, with users ecstatic over the quality of the merchandise.

The US government has been making intelligence imagery available to researchers since the late 1990s under a program codenamed MEDEA, but the researchers had to have a security clearance to gain access. Last fall, US intelligence agencies asked the US National Academy of Sciences (NAS) if a public release of such imagery, screened to ensure it revealed nothing that might compromise national security, would be useful. An NAS panel replied, in effect: "Of course!" That was apparently the answer that was expected, since the imagery was available within hours of the response. While the intelligence services are making no promises, it appears that having set the precedent, more data is going to be provided as it becomes available and is properly filtered for civilian use.

* There was a buzz going around the science blogosphere about the latest fossil find -- it seems we get something new and interesting every month or two. In this case it was a tyrannosaurid, along the ancestral line of the great Tyrannosaurus rex, named Raptorex kreigsteini. The fossil had been found in China and was dated back about 130 million years. It was about the size of a human, and it was judged to be an adolescent that had nearly reached adulthood. The age of an animal can be judged from the level of fusion of its bones, which increases with maturity; the pelvis of Raptorex was fully fused, while shoulder blade was nearly so.

The particularly interesting thing about Raptorex was that its proportions and features were very similar to those of T. rex even though Raptorex was 90 times smaller. This simple scaling of form is not seen in other lineages of dinosaurs, which tend to change configuration as they get bigger. One interesting feature of Raptorex is that, like the T.rex, it has dinky forearms; it has been suggested that the dinky forearms of T. rex were vestigial, performing no real function, but if they hadn't been useful it would be unlikely they would have been retained for tens of millions of years of evolution.

* Not long after this, the buzz shifted to another new find, fossils of a "pterosaur" or flying reptile named Darwinopterus, discovered in China and dating back about 160 million years. Early pterosaurs had long tails; later species had short tails and other different features. Darwinopterus appears to be an intermediate form -- the clumsy term "missing link" being avoided here -- but was something unexpected, demonstrating what is known as "modular" or "mosaic" evolution.

Darwinopterus

It is intuitive and tempting to believe that any species of an organism that is intermediate between an earlier ancestral species and a later descendant species will be intermediate between ancestor and descendant in all respects, but that's not how evolution necessarily works. Not all features change at the same rate, and there's no particular reason to think that they should; some features may evolve early on from ancestors, while other features will arise much later. Darwinopterus demonstrates such mosaic evolution, with a body that strongly resembles ancestral forms, along with a head and neck that strongly resembles descendant forms. It has proven something of a surprise and is a valuable addition to the family tree of the pterosaurs.

* I mentioned on the message board that the internet seems to encourage attention deficit disorder by providing an environment where it is very easy to jump haphazardly and rapidly from one subject to another. I was half joking, but a note in AAAS SCIENCE suggests I was more on the mark than I thought. Researchers at Stanford University in California conducted a cognitive psychology study on "multitaskers" who jumped from task to task, comparing scores on various cognitive tests with the scores of a control group. The multitaskers scored lower on every test, with one of the researchers running the experiment saying that they were "bad at every cognitive control task necessary for multitasking."

This was judged somewhat worrying since high-tech society is producing information overload, and it's getting steadily more severe. My experience in the Corporate world made be laugh when the same researcher added that "people who chronically multitask believe they're good at it." Yeah, I've heard that one before. Personally, I'm starting to make a rule to refuse to be easily distracted from a task I'm working on: juggling tasks is something I end up having to do, but the less I have to do it, the better off I am.

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[WED 28 OCT 09] REMEMBER EVERYTHING

* REMEMBER EVERYTHING: An article in WIRED magazine ("Total Recall" by Gary Marcus, April 2009) took a snapshot of Jill Price, a middle-aged school administrator from Los Angeles, California, who has the unusual trait of remembering everything that has happened to her. Asked when a particular episode of a TV program was played, she gives the date and the weather outside at the time; asked when a celebrity died, she gives the day and what she was doing at the time.

People who knew Price were aware of her remarkable memory, but she didn't become noticed by the outside world until 2000, when she ran across the web page of a University of California at Irvine neuroscientist named James McGaugh, who works on issues in learning and memory. She contacted McGaugh and told him about her unusual memory; McGaugh was skeptical -- researchers get contacted by dubious characters on a regular basis -- but he was curious enough to investigate. He found out that Price was the real thing.

McGaugh and two other neuroscientists worked with Price, finally releasing a paper on her in 2006. The UC Irvine press office told a local newspaper about the study, and ran an article in response. Within a few weeks, Price was on National Public Radio, and following that made appearances on talk TV. She is now a minor celebrity and has published her memoirs. The author of the WIRED article, Gary Marcus, is a professor of cognitive psychology. He decided to investigate Price himself, and though he was also skeptical at first, concluded after working with her for two days that she was the real thing -- with some significant qualifications.

Computers have memories that store information in the form it is provided to them indefinitely; no matter how long the interval to the time when the information is retrieved, if the mass storage system is working properly the data is exactly the same as it was when it was stored. A human memory does not work in such a precise fashion; memories overlap, overlay, and fade out in ways that are not well understood. A human with a memory like a computer mass storage system would be like a person with bones made of titanium.

Marcus found that Price could instantly list dates of famous accidents and say what she was doing at the time; she could also identify such an accident just given the date. She could list everything she'd done on an Easter since 1980. However, on further investigation, Marcus found Price was no better than anyone else at remembering things she learned in history or math class; she struggled in school. Marcus ran tests of memory retention -- telling her a series of words and then asking her to repeat them, and so on -- and found her retention not much different from average.

However, Price does still have an astonishing recollection of her personal history and certain categories of events, such as TV shows and prominent accidents. Why? Because she continually reviews her own past. She's a memory packrat who never throws anything of her past away. She has every stuffed toy she ever received, she has thousands of video and audio tapes, she has tens of thousands of pages of diary entries -- entered in a small dense script that looks a bit like shorthand and which few would find easy to read.

Price has lived with her parents all her life, and her inclination to hoard her memories seems to have begun after her family moved from South Orange, New Jersey, to Los Angeles in 1974, when she was a grade-schooler. From that time on, she kept detailed record of everything she did. She remembers her life because she spends much of her time working at it. Price's brain was scanned a few years back and there was nothing unusual about it -- except for traits associated with obsessive-compulsive disorder (OCD).

Three other "hyperthymestics" like Price have come forward since she went public, and all three were found to have similar OCD-like symptoms, restlessly and relentlessly writing down everything that happened to them. While the hype around Price tends to make her sound superhuman, Marcus suggests that anyone could have the same recall if they saw a need to make the effort. Marcus, however, does not lowball Price's abilities, calling her the "Michael Jordan of autobiography". Jordan became a super basketball player by practicing relentlessly, developing an existing talent into top-ranked skill. Price's ability is not magic: she worked for it, and however outside of the box it is, she deserves whatever rewards she can get for it.

ED: I have a slight identification with Price. A friend once told me: "My sister has a photographic memory; she remembers everything she sees. I have a phonographic memory; I remember everything I hear." I replied: "I have a typographic memory. I write everything down."

Unlike Price, however, I have little interest in recording my own past. I'm bookish, as a subject I bore myself, the rest of the world is more interesting. I have been keeping an activity log for the past few months, but it's a time-management exercise. I write up travelogues, but it's only to recall places I visited, and make notes for future trips.

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[TUE 27 OCT 09] MORE FLU FRENZY

* MORE FLU FRENZY: The current frenzy over H1N1 swine flu was discussed here two weeks ago; since that time, it seems to have intensified. On 24 October, US President Barack Obama declared the current swine flu pandemic a "national emergency", the intent being to relax Federal requirements for those working to respond to the crisis. The swine flu virus has been reported in 46 states so far and a thousand deaths have been linked to it.

At roughly the same time, WIRED magazine published an extended article by journalist Amy Wallace titled "An Epidemic Of Fear" on the antivaccine crusade. It was a clear slap at the antivaxers, denouncing them in detail, with the article supported by sidebars that linked to resources and discussed various hot points:

The antivaxers have been repeatedly criticized for ignoring the issue of levels; after all, botulism toxin is so incredibly toxic that it is a common biowar agent, but highly diluted "botox" is routinely injected into humans as a beauty treatment.

There's also been a fuss about the use of a chemical known as "squalene" as an "adjuvant" (immune-system stimulator) in vaccines, with antivaxers sternly asking: "Do you want YOUR kids injected with SQUALENE?" -- it seems because the word "squalene" sounds scary. Actually, according to the World Health Organization, it's a fat produced by the liver and circulates in our bloodstream. It's common in foods and in cosmetics, and ironically it can be found in health food stores as "shark liver oil".

Squalene by itself is not actually an adjuvant, but it works as one in combination with other vaccine components. Tens of millions of vaccines containing squalene have been administered with no particular record of ill effects. Attempts to blame the Gulf War Syndrome on vaccines containing squalene administered to the troops fell through when it was learned the vaccines in question did not contain squalene.

* The article got massive attention, with heavy traffic to the WIRED website and an expanding wave of commentary in the blogosphere. Of course WIRED and Amy Wallace were loudly denounced by the antivaxer community, with some hints that they were stooges for the pharmaceutical industry. The natural health and alternative medicine websites seem to have some enthusiasm for antivaxer activities, with articles presenting the swine flu vaccine as hazardous and some even claiming that vaccination is unnecessary. One item that made the rounds was a list of "Ten Questions About Flu Vaccines That Doctors And Health Authorities Refuse To Answer". While many of the items on the list were obscure and difficult to assess one way or another, one item flatly claimed that vaccines were unnecessary, that humans had long survived without them:

BEGIN QUOTE:

Human genetic code is already wired to automatically defend you against invading microorganisms (as long as you have vitamin D).

END QUOTE

It appears that adequate vitamin D is in fact an important component of a healthy immune system, supporting the innate immune response and helping regulate the immune system, inhibiting autoimmune disease. However, by itself vitamin D can do nothing to prime the adaptive immune system to recognize an unfamiliar pathogen, and the influenza virus has a serious expertise at making itself seem unfamiliar. The implication that humans were getting along just dandy before the nasty vaccines were developed was so shocking -- in light of a long history of ghastly catastrophes like the 1918 flu pandemic -- that it immediately destroyed the credibility of the other entries. It was so difficult to accept that it seemed hard to believe the author actually meant what the comment seemed to say.

* The issue has been surfacing on YouTube as well, with videos circulating about a cheerleader named Desiree Jennings who had come down with a nasty neurological disorder after getting a seasonal flu vaccine shot. Although there were hot-headed accusations of "hoax" that got downright foul-mouthed abusive in places, Jennings does appear to be sincerely ill. However, nobody else who got a shot from that batch of vaccine demonstrated an adverse reaction, and the illness followed the flu shot after an interval of ten days. The woman was hardly quarantined in a sterile environment either before or after getting the shot, and in the absence of any controls there's no way to rule out the actual cause being some unknown event completely unrelated to the flu shot. The possible connection to the flu shot is unsettling, but with no other cases to report, it's difficult to establish a strong causative link between her illness and the vaccination, and saying there was one or not is an unsupported guess either way.

Another recent case, in the UK, in which a 14-year-old schoolgirl named Natalie Morton died shortly after getting a cervical cancer virus vaccine in Coventry, was also played up by the antivaxers -- with the fuss coming to an abrupt halt when an autopsy showed the unfortunate girl had a large, undiagnosed tumor in her chest that had spread into her heart and left lung. Over a million girls in the UK have received the same vaccine, with no substantiated reports of ill effects. Astoundingly, although the girl's parents accepted the judgement of the coroner, some of the more extreme antivaxers didn't give it up then, claiming the autopsy was a "cover-up" orchestrated by the vaccine industry, involving collusion with the Coventry coroner's office.

* ED: The swine flu virus seems to have acquired a "hitchhiker" virus in cyberspace. When I saw the video about the cheerleader, I started poking around on Google on the matter. Some of the "hits" suggested that the incident was a hoax, and so I followed up the link -- to get a clearly fake "Your Computer Is Infected With A Virus" popup message.

I promptly killed the popup, but I did something wrong and a download followed. I killed that in turn, but though I doubt that it completed, it still screwed up my PC. I tried to run system restore, but nothing happened, which was a bad sign: the first thing malware often does is disable PC defenses. I had to do a reboot and a system restore; after some hassles I got things working again.

Here's the puzzle. I searched again on the "cheerleader hoax" business, and got the same fake popup. This time I used Task Manager to kill my browser to make sure I didn't get infected again. Then I went through the drill several more times, picking up on different links; it turned out that there was more than one website out there running the same scam, with some site claiming to be in Pakistan appearing to be at the center of it all. It appears scammers are monitoring Google for current hot topics and then coming up with scamsites to exploit popular searches.

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[MON 26 OCT 09] SOUTHWEST ROAD TRIP (1)

* SOUTHWEST ROAD TRIP (1): I was thinking of taking my twice-yearly road trip from Colorado to Spokane this year in early November and then looping down to Las Vegas to catch the AVIATION NATION air show at nearby Nellis Air Force base -- but I found out that it was in mid-November this year and that made me nervous about getting over the Rockies. The odds were I could, but a snap storm could easily leave me stranded or worse. Besides, I'm no fan of Las Vegas.

So I got to thinking about the alternative, the Commemorative (Confederate) Air Force (CAF) "AirSho" at Midland, in West Texas, in early October. It was only a day's drive and there were no mountain passes to traverse; the more I thought about it, the more I liked the idea. I figured I could drive south to New Mexico, see some sights there, cut across to West Texas, catch the airshow, and then come home. I could take a quick trip to Spokane in September and still have budget and time for the Texas trip the next month.

I made the Spokane trip and didn't start getting the Texas trip nailed down until the first of October. That gave less than a week to prepare -- enough time, but it was a bit frantic, and I wondered if I should bother with it. I'd been to the warbirds airshow in Chino, California some years back and the CAF AirSho looked similar, and my last extended road trip had been nothing I wanted to repeat. However, I hadn't got out of the house much all year; I knew I would continue to think about visiting the AirSho until I went; and the trip was neither particularly expensive nor troublesome. There's no way I felt up to another ten-day road trip, but this was only five, and not a demanding five days either.

I shrugged and went ahead. I made my motel reservations, checked on locations and operating hours of attractions, printed out maps, and figured out what I needed to pack. I usually like to have about two weeks to plan out a trip; I have to fit in the effort with my usual schedule, and I find if I get in a rush I don't review and double-check on things, which means I can miss or forget obscure but useful, even important details. I still recall going to Ashfall State Park in Nebraska and finding out it was closed on Mondays. Besides, scheduling can be a surprisingly complicated task -- in fact, industrial scheduling software has a reputation for complexity. The other factor is that at home, everything's pretty much reduced to a routine and resources are on hand to deal with the unexpected, but once on the road away from home, the unexpected can be much more troublesome.

* I left Loveland, Colorado, dark and early on Wednesday, 7 October, to drive to Santa Fe, New Mexico. It wasn't a really long drive -- 725 kilometers (450 miles) -- but I had to leave the house at 0500 AM to get through downtown Denver before rush hour started.

Since I had plenty of time, I decided to drop by the zoo in Pueblo, Colorado, never having visited it before. It opened at 0900 AM, and getting through Denver early meant I had about a half-hour to kill before I could get in, so I went to the local airport in hopes of finding something interesting. There was an air museum there with about a dozen aircraft on open display, but it was one of these infuriating "boneyard" operations where irreplaceable old warbirds were left to rot. I did get some shots of a Bell Kiowa / Jetranger on the airport flightline -- it was an olive-drab government machine, mysteriously only labeled as "UNITED STATES" -- but it was still too cloudy and dim so the shots didn't come out. They did have an old Republic F-84 Thunderjet fighter on a pylon that was in fair shape and I got reasonable shots of it.

I made my way across town to the zoo. It was in the city park; the zoo hadn't opened yet, but it was in the city park and so I wandered around for a while, taking a shot of a nice new colorful waterslide at the inactive city pool. Once the zoo opened, I went to the ticket stall and nobody was there; I shrugged, went inside the office building, opened a door to where the staff were milling around, and said: "Hallo!"

"Yes? What can we do for you?"

"Well, I was figuring I'd pay admission but if I'll go in free if it's okay with you."

"Oh, a customer!"

"A CUSTOMER -- what a RADICAL concept!" I got a dirty look.

In any case, the Pueblo zoo was a fairly average small zoo, could have been in better shape -- one whole section was effectively abandoned -- but as is typical of any zoo it had its virtues. There was a nice indoor squirrel monkey enclosure, I must've taken thirty shots to nail the little critters down, but between bad lighting and their hyperactive mobility it was hopeless; none turned out. In compensation, I got some fair shots of a hyrax in an enclosure next to the monkeys, and a really pro-quality shot of a pair of Balinese mynahs across the hall, very pretty white birds with blue eye-shadowing. Outdoors, I found a paddock with llamas and being fond of the beasts had to take shots there -- when one of them walked towards me in curiosity and I realized it was an alpaca, which I'd never seen in the flesh before. Funny looking woolly creature, looks like a cross between a llama and a giant poodle.

Balinese white mynahs

* The rest of the day was just completing the journey. I had to make a stop at a Walmart -- I knew I would forget something in the relative haste in which I'd planned the trip, and when the batteries ran out on one of my cameras, I realized I'd forgotten the pack of AA cells I'd bought for the trip. No big deal, I bought a 20-pack -- my zoom camera uses four, my pocket camera uses two, and on trips I carry an old very tiny Nikon Coolpix camera that uses two, the Coolpix being useful in special cases. Anyway, it was handy to keep a pile of AA cells around.

Once I got into northern New Mexico, I found the terrain tended to resemble that of Wyoming, wide open spaces with hills and mesas, but there's a tendency towards juniper forest, something like seas of shrubberies among hills and mesas. I made it to Santa Fe that afternoon, to find it not all that interesting. Acquaintances from New Mexico had told me it was a nice place for those with artsy inclinations, but that's not me. The TripAdvisor website's listing for things to do in Santa Fe was tilted very heavily towards arts museums and the like, which helped reinforce my suspicions. I thought I might be able to find some interesting public sculpture displays, but I couldn't figure out any way to scout them out online. On arrival I noticed that the abode motif seemed to be part of the local building code, even the McDonald's where I stopped to get something to eat was in the adobe style.

I checked into a motel; when I got to my room, I pulled out my laptop to log my day's expenditures on a spreadsheet, but the OpenOffice system then asked to perform an update, and I said YES. Alas, auto-updates sometimes have a tendency to get "wedged" and it happened this time, going from one bad thing to another, until in frustration I simply deleted OpenOffice and redownloaded it -- 150 MB over the motel's wi-fi network, which seemed to vary in speed over a wide range. I did manage to get my expenditures logged before I went to bed. [TO BE CONTINUED]

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[FRI 23 OCT 09] THE PARASITES (24)

* THE PARASITES (24): Parasites have clearly had considerable effects on human evolution. As humans spread over the planet, they encountered unfamiliar parasites and were infected by them, with the parasites evolving to adapt to the new hosts. Changes in lifestyle, such as the shift from hunter-gatherer culture to farming, also brought humans into contact with parasites humans had not encountered before.

Humans acquired countermeasures against parasites as well, the most famous example being that of "sickle-cell anemia". Sickle-cell anemia is found in peoples with origins in malarial regions; in the United States, it is most associated with black Americans, but it is by no means exclusive to blacks. It is a genetic disease, generally harmless if a subject only has the gene for it on one chromosome, but causing severe anemia by the deformation of red blood cells if a subject has the gene for it on both chromosomes. The reason that the disease shows up in malarial regions is the fact that the single-dose variant leaves red blood cells selectively fragile, making them difficult for the malarial Plasmodium parasite to infect without destroying them. Had malaria not been a factor, the sickle-cell gene would have gradually died out. There are a number of other genetic idiosyncrasies of populations in malarial regions that seem linked to the prevalence of the Plasmodium parasite.

Now humans have acquired technologies to fight back against parasites. It hasn't been easy; drugs have been developed to kill parasites, but in time the parasites acquire resistance to the drugs, particularly if the drugs are used indiscriminately. Given the stealthy behavior of parasites like Plasmodium, vaccines have proven tricky to develop. The most effective approaches to dealing with parasites so far have been preventative -- efforts to eradicate tsetse flies have rendered inhabitable parts of Africa where humans were certain to be killed off by sleeping sickness. However, preventative measures generally require ongoing effort and expense.

The idea that we can completely destroy parasites forever is unrealistic. We can figure out means of protecting ourselves from them, but to an extent we have to understand them and determine how to coexist with them. Indeed, it is suspected that the high incidence of afflictions such as asthma among children in relatively sanitized wealthy societies may be a result of the isolation of children from parasites. Such diseases are rare in poor, unsanitary societies, suggesting that exposure to parasites from birth is required for the formation of a well-functioning immune system. Nobody is proposing that children be infected with worms as a public-health measure -- though it has been done to some adult patients with immune system disorders and with some evidence of success -- but it might prove useful to inject children with parasitic proteins to stimulate their immune systems.

Parasitology is not a pretty subject, and it is easy to see those working in it as morbid ghouls. That's a superficial read on things -- people in poor countries know that parasites are important, as important as a gun stuck to the head. Certainly, from a clinical point of view, parasites can be fascinating beasts, though it's a fascination most find hard to sympathize with. However, the bottom line is that the more we know about parasites, the better we will be able to cope with them, and the healthier we will be as a result. [END OF SERIES]

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[THU 22 OCT 09] GIMMICKS & GADGETS

* GIMMICKS & GADGETS: As reported by THE ECONOMIST, prepaid cards AKA "gift cards" are becoming very popular with governments. Following the fighting in Pakistan's wild frontier region earlier this year, the Pakistani government ended up with 1.5 million refugees to take care of. Exercising some imagination, in June the government teamed up local banks and charge card giant Visa to distribute 230,000 cards, one per family -- each loaded with the equivalent of $300 USD and redeemable for food and medicine at any of 500 terminals around the refugee camps.

This is a high-profile example of a global trend. Visa is involved in similar schemes in the Philippines, Mexico, Brazil, Costa Rica, and the Dominican Republic -- where 800,000 citizens get food aid, fuel subsidies, and even rewards for going to school. Rival charge-card company MasterCard is running comparable programs in Poland and Peru. It's not just the poorer countries that are involved, either, with 34 US states providing benefits on prepaid cards, or at least planning on doing so.

Prepaid cards are popular simply because they work. A Nebraska state official says it costs a penny to set up a prepaid card account, while sending out a check costs 60 cents; it also ends up being less costly in terms of handling end user issues, since there aren't so many complaints about lost checks. End users don't have to worry about check-cashing fees, and they find prepaid cards much more convenient to use and much more secure.

Pakistan's prepaid card program is backed up by a biometric database to help assure security. The Pakistanis see particular benefits in using prepaid cards -- one being that the recipients are from a culture where being handed cash on a charity basis is humiliating, while the cards provide a level of indirection that saves face. The Pakistanis also see the cards as a way of getting poor folk involved with modern financial systems.

* A WIRED Online blog entry discussed interesting gadgets from a company named KILLA, in the form of backpacks and swatchel bags with a built-in flexible solar panel and an external interface to control an iPod, iPhone, or other Bluetooth-enabled device. The backpacks and satchels are actually derived from World War II-vintage German designs. The KILLA products are being produced in low volume and are likely expensive, but the basic concept seems interesting, looking forward to a future time where a kit bag could be covered with cheap, low-efficiency flexible solar cells to power the electronic gear technogeeks are fond of hauling around.

* The WIRED Online blogs also described an interesting new transport concept named "SpeedWay", developed by a German engineer named Christian Foerg. It's based on little two-seater pod-style electrocars with two wheels -- in a side-by-side arrangement instead of tandem, presumably using Segway-style stabilization -- with a range of up to 200 kilometers (120 miles) per charge for city traffic.

Christian Foerg's Speedway cars

However, the little cars can also be used for long-range highway travel, using a linear induction motor built into the roadway itself. The cars tilt down for high-speed operation; the linear induction motor also recharges the car batteries while propelling the cars at high speed. Once off the highway, the cars revert to battery power. The small size of the cars allows them to be easily parked; Foerg's concepts envision a high-rise cylindrical parking garage that hauls the cars up and down on elevators.

The idea has some broad similarity to a giant toy slot-car system. Foerg believes it has advantages in terms of efficient use of electrical power and because other vehicles can still use the roadway. It's a very sexy concept, if not entirely convincing as a practical scheme. It seems it wasn't supposed to be: Foerg is an industrial designer playing with blue-sky ideas for a thesis.

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[WED 21 OCT 09] COMBINED-EFFECTS EMP MUNITIONS

* COMBINED-EFFECTS EMP MUNITIONS: The military has been tinkering with electromagnetic pulse (EMP) munitions for some years now, in hopes of developing weapons that could fry an adversary's electronic gear without causing other damage. As reported in an article from DEFENSE TECHNOLOGY INTERNATIONAL ("E-Bombs Could Go Mainstream" by David Hambling, 11 March 2009), military forces have not been enthusiastic about such "soft" weapons, seeing their combat effectiveness as uncertain: when the troops hit a target, they want to know that it's really dead.

However, what if an EMP capability could be cheaply added to a normal explosive bomb or warhead? Such a "combined effects EMP munition" would be, from the warfighter's point of view, a very attractive option, allowing a bomb to inflict damage on targets even outside the blast zone, or still knock out a tank if the blast itself failed to do the job. At the very least, the EMP would throw systems offline or force a reboot; at the best, it would fry electrical components.

An electromagnetic field is created by a changing electric current; the greater the current and the faster the change, the stronger the field. A "soft" EMP munition is built around a "magnetic flux compression generator", consisting of metal coils carrying current that are imploded by an explosion. This scheme is not well-suited to integration into an ordinary explosive munition. The US Army has explored an alternative scheme, the "shockwave ferromagnetic generator", in which a certain type of magnet is blown up, spontaneously demagnetizing in the process and releasing an EMP. The phenomenon is known as "pressure-induced magnetic phase transition".

In 2005 Army researchers, working with contractor Loke and Texas Tech University, demonstrated a shockwave generator based on ordinary neodymium alloy magnets, commonly used in speakers and headphones. Having proven the concept, the research team then went on to more exotic lead zirconate titanate magnets, shrinking the volume of the system by an order of magnitude. The goal is to develop a module containing the generator element, power conditioning system, and aerial in a 16 cubic centimeter (1 inch) volume, capable of generating hundreds of megawatts of emitted power for microseconds.

Construction of an aerial that can be crammed into such a small volume and operate while it is being exploded is of course challenging, and the researchers are focusing on using the explosion itself to provide the aerial, implemented as a jet of plasma. It is tricky to generate this "plasma antenna" without compromising the normal blast effects of a munition. Testing such combined effects EMP munitions also promises to be tricky: blast effect on a target is relatively easy to assess, but the effects of an EMP accompanying an explosion are not easy to predict, being confounded by factors such as position and electrical shielding. Coming up with a realistic test program to show that the EMP enhancements will be worth their price is going to be a challenge.

Candidate weapons for carriage of a combined effects EMP warhead include the TOW antitank missile and the classic 70 millimeter (2.75 inch) unguided rocket. Nobody is expecting such relatively light weapons to produce EMP pulses over a wide area -- which is not such a bad thing, since it means they can be used in close vicinity to friendly forces -- but they will hopefully be able to inflict enhanced damage in the target area. Some thought is being given to adding an EMP capability to even lighter munitions, such as antitank rockets carried by infantry.

The US Air Force is not saying much about their work with combined effects EMP munitions, but they would seem a valuable addition to air-to-air missiles since modern combat aircraft are crammed with sophisticated and vulnerable electronics. The US Navy is experimenting with an EMP device that can fry the detonators of improvised explosive devices (IEDs) and disable them without setting them off, reducing collateral damage. The Navy effort has gone quiet publicly, suggesting that it may be ready for fielding.

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[TUE 20 OCT 09] BUG SPATTERS FOR SCIENCE

* BUG SPATTERS FOR SCIENCE: One of the inevitable drawbacks of taking a long road trip in warm weather is the carpeting of bugs that ends up smeared all over the front of the car, which can be laborious and unpleasant to clean off. As reported by WIRED Online, a genomics researcher from Pennsylvania State University named Anton Nekrutenko took a Zen approach to the matter, coming to the realization that his car made an excellent tool for obtaining a genetic sample of the varieties of flying insects in a particular region. Nekrutenko and his colleagues sequenced the DNA from the spatterings of insects obtained on two different road trips -- one from Pennsylvania to Connecticut, the other from Maine to New Brunswick in Canada. The analysis demonstrated there were significant differences in the flying insect populations between the two regions, even though they were relatively close together.

More generally, the study was a pioneer in the expanded use of "metagenomics" -- the genetic analysis of entire ecosystems. In the past, metagenomics has generally focused on bacterial ecosystems, such as the bacteria that inhabit our gut or live on our skin. Performing a metagenomic analysis on insects was something new, as well as more complicated; not only did collection require a different (if decidedly brute-force) approach, but insect genomes are as a rule much more complicated than bacterial genomes.

To help in the effort, the Penn State researchers worked with colleagues at other institutions to develop a web-based software application named "Galaxy" that could guide a researcher through the steps of metagenomic analysis, from obtaining raw genetic data to coming up with an evolutionary tree. Galaxy also allows users to share their results, easing collaborations and independent verification of the results obtained by one research team by others. Galaxy is now being used on a variety of metagenomics projects, with rave reviews.

Oddly, the Penn State study turned up a large number of matches to human gene sequences. Nekrutenko believes that they are just artifacts, that our current genomic knowledge is heavily biased towards the human genome, and so false matches are more common than they should be. Nekrutenko says: "Precise species ID from mixed samples like this is very, very challenging. We have sequences that map to human DNA, even though I'm pretty sure we didn't kill anyone." Science, as the saying goes, isn't completely an exact science.

* In somewhat related news, AAAS SCIENCE reported on an effort by a team of researchers at the University of Turku in Finland to try to zero in on the evolution of butterflies. Butterflies are of course delicate creatures and as a result they don't fossilize well; the oldest of the handful of fossils available places them back about 35 million years, but given the scarcity of data, nobody believed that was the last word on the subject.

The Finnish research effort began about a decade ago and focused on using genetic analysis to come up with a family tree for the Nymphalid butterflies, which include the monarch and other spectacular butterfly species. The Nymphalids cover 540 genera; the researchers obtained samples of 400 of them for the analysis, sequencing ten genetic markers and characterizing 235 distinct features -- such as the pattern of veins on the wings -- for a taxonomic analysis.

Nymphalid butterfly

The family tree that was finally assembled gave the relative eras of the emergence of the members of the Nymphalids, but given the scarcity of fossils, calibration with the fossil record was problematic. The researchers assumed that since Nymphalids such as monarchs pollinate milkweeds today, the fossil record of milkweeds might make a good calibration marker for Nymphalid evolution. On the basis of this assumption, the Nymphalids appear to have emerged about 90 million years ago, during the Cretaceous, the last period of the dinosaurs.

Reinforcing the assumption, the rate of emergence of new Nymphalid species underwent a temporary but clear slowing about 64 million years ago -- roughly at the time of the extinction of the dinosaurs, suggesting that butterflies also suffered from the global extinction event. The study still leaves much to be learned about the evolution of butterflies, but it has been praised for its thoroughness and ingenuity.

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[MON 19 OCT 09] NEW OPTIONS FOR HUMAN SPACEFLIGHT (4)

* NEW OPTIONS FOR HUMAN SPACEFLIGHT (4): The Augustine Committee's report on options for the US in human spaceflight created a buzz among the amateur and professional space community, speculating on which of the report's options the Obama Administration will select. Nobody's exactly sure when that will happen, since the administration is currently wrapped up in the painful health-care debate, but the administration needs to make a decision before establishing the NASA budget for 2010.

The president recently stated that he favors raising NASA's budget to maintain a human spaceflight capability, but what options will be exercised remains unclear. Preliminary indications suggest that the Ares I will be canceled in favor of a commercial route to LEO crew service, and that the lifetime of the ISS will be extended to 2020. Although it seems likely the Ares V heavylift booster will be dropped, the status of an alternative heavylift vehicle development program -- Ares V Lite, Shuttle C, or enhanced EELV -- is not apparent just yet. It is believed the Altair lunar lander will be killed, with the administration opting for Flexible Path missions to an asteroid, the Lagrange points, and so on. More ambitious missions, such as a Moon landing, would imply international cooperation, for example with the European Space Agency and other partners building a Moon landing system.

Obviously, the final decision is going to be tricky, since the Obama Administration is trying to hold the line on deficits, while Congress will fight cuts in space programs that provide jobs to constituents. Commercial space firms like Orbital Sciences and SpaceX promise to win big in the new space order -- and in fact commercial space seems like the big wildcard in future developments, promising a new way of doing things, though one that poses substantial risk. Older aerospace giants like Lockheed Martin are already demonstrating that they feel threatened and are playing up the risk.

The real worry is that decisions will be made that simply allow NASA to limp along as it has for decades, working towards poorly-thought-out goals with inadequate funds. In the early 1960s, President John Kennedy gave NASA a mandate to put Americans on the Moon in a decade, and the agency performed the task with impressive efficiency. Although NASA has accomplished much since that time, few would perceive overall efficiency in its actions. Of course, much of the trouble came from failures of political leadership, and one can only hope that the Obama Administration will do a better job than its predecessors. As has been pointed out, NASA is now caught up in executing programs that were put in motion three to four decades ago, and decisions made now will determine the agency's direction for decades to come.

* For the time being, NASA is continuing work on the status quo, with preliminary redesign work being conducted on the Ares capsule to reduce it to four crew instead of six. Tests of its rocket escape system are continuing, and launch of a "boilerplate" Ares I is pending -- though the booster may get the axe before that happens.

not-Shuttle-C

There was some amusement among the space community at the resurrection of Shuttle-C, with a posting on a forum showing a picture of Captain Picard of the Starship ENTERPRISE rubbing his hand across his forehead as though pained, with the caption saying: "Oh NO, not this again!" It was carefully presented by NASA as a new idea, even though it predates the first shuttle launch and has been described as "the most studied launch vehicle ever." The new incarnation does break with earlier concepts in some ways, but it would be an understatement to say that the "Not Shuttle-C", as it's been called, has a certain resemblance to older Shuttle-C concepts.

One of the unsettling things about the Augustine Committee was that it was only focused on human spaceflight. That made sense, since that was where the real problem lay, but most of NASA's major successes in the post-Apollo era have been in unmanned space missions. When a formal plan emerges from the Obama Administration, it will be interesting to see what it says, if anything, about unmanned space. [END OF SERIES]

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[FRI 16 OCT 09] THE PARASITES (23)

* THE PARASITES (23): The arms race between parasite and host may end up being peculiarly cyclical, with parasites becoming murderously effective against some subset of a host species and all but destroying it, to then start over by attacking another subset of the host species ... and eventually working their adaptations around in a cycle to the original subset, which had restored its numbers in the meantime. In the long run, it may not be a vision so much of parasite and host trying to overtake each other in a race with ever greater evolutionary refinements -- as it is something like an aerial dogfight, with each contender turning in loops, trying to get on the other's tail.

It is strongly suspected that the challenge of parasitism was one of the main drivers for the origins of sexual reproduction as a scheme in this evolutionary dogfight. Sex is elaborate and imposes a certain amount of overhead, most significantly males that don't bear young. There are plenty of organisms that don't need sex to reproduce, and it would seem that since all members of such asexually-reproducing species can bear young, they would quickly out-reproduce sexual reproducers and put them out of business.

Obviously sex has advantages, and there are a number of different ideas, not all of them mutually exclusive by any means, as to what they are. One of the most popular notion's is called the "Red Queen's race", from the scene in Lewis Carrol's ALICE stories where the Red Queen must race as fast as she can just to stay in one place, just as the two dogfighters turn as hard as they can but are hard-pressed to get an advantage.

Large organisms tend to have long lives and long reproductive cycles, while the parasites that attack them tend to have short lives and short reproductive cycles. That means that parasites tend to evolve faster than hosts. The problem with asexual reproduction is that it generates populations of clones, and if a parasite acquires the ability to penetrate the defenses of any member of that population, it then can cut through the clones like a scythe. Sexual reproduction scrambles the genomes of parents, meaning that offspring will have new combinations of characteristics -- most significantly in this case a rearranged immune system -- that the parasite will have to crack once more.

The Red Queen's Race

* The threat of parasites has also influenced means of courtship among animals. Darwin was puzzled by the elaborate tails of peacocks, seeing them as useless exuberance that should have been trimmed by natural selection. He came up with a complementary idea, which he called "sexual selection", in which exaggerated features such as a peacock's tail were due to the competition to obtain mates. Peacocks competed for the attention of hens; the peacocks with the flashiest tails got the hens, and so propagated ever larger tails.

The whole notion of sexual selection turned out to be subtler than Darwin thought, and since his time has been very highly refined. One interesting notion in modern times is that the peacock's tail is not useless at all. A peacock has to invest a lot of energy into maintaining an attractive tail; if the peacock is being dragged down by parasites, there's no way it will have a tail that can attract females. The tail is an advertisement that the peacock is parasite-free and will be a good father. The same goes for other displays, like the wattles of tom turkeys, which will only appear bright red if the toms are healthy. [TO BE CONTINUED]

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[THU 15 OCT 09] SPACE NEWS

* SPACE NEWS: Space launches for September included:

-- 08 SEP 09 / PAN (USA 207) -- An Atlas 5 booster was launched from Cape Canaveral in Florida to put a secret US government payload into orbit. The payload was a geostationary communications satellite known only as "PAN" or "USA 207"; it was built by Lockheed Martin. The Atlas 5 flew in the 401 configuration, with a 4 meter (13.1 foot) fairing, no solid rocket boosters, and an upper stage with a single Centaur engine.

-- 10 SEP 09 / HTV 1 -- A Japanese JAXA H-2B booster was launched from Tanegashima island to put the first "H-2 Transfer Vehicle (HTV)" into space. It was an unmanned cargo vehicle, designed for International Space Station (ISS) support missions and with a cargo capacity of 4.5 tonnes (4.95 tons). It docked with the ISS on 17 September.

HTV rendezvous with ISS

-- 17 SEP 09 / METEOR M1 -- A Soyuz Fregat booster was launched from Baikonur in Kazakhstan to put the "Meteor M1" polar-orbit weather satellite into orbit. Although the Meteor satellite series has been in service for decades, this was the first launch of the new "Meteor M" series spacecraft. Meteor M1 had a launch mass of 2,720 kilograms (6,000 pounds), a design life of five years, and carried an instrument suite of six instruments, including a radar to map polar ice. The launch also included a set of smallsats:

In addition, the Fregat upper stage carried a space inflatable technology experiment named the "Inflatable & RIgidizable Structure (IRIS)".

-- 17 SEP 09 / NIMIQ 5 -- A Proton Breeze M booster was launched from Baikonur to put the Canadian Telesat "Nimiq 5" geostationary comsat into orbit. Nimiq 5 was built by Space Systems / Loral and was based on the SS/L 1300 comsat platform. It had a launch mass of 4,745 kilograms (10,460 pounds), carried a payload of 32 Ku-band transponders, and had a design life of 15 years. It was placed in the geostationary slot at 72.7 degrees West longitude to provide direct-to-home services to North America.

-- 23 SEP 09 / OCEANSAT 2 -- An Indian ISRO Polar Satellite Launch Vehicle (PSLV) was launched from Sriharikota island to put the Indian "OceanSat 2" oceanic observation satellite into orbit. OceanSat 2 had a launch mass of kilograms (2,112 pounds) and carried a payload of three sensors:

The launch also included a set of CubeSat nanosats:

Finally, the PSLV upper stage carried two attached payloads named "Rubin" to test the "Automatic Identification System", a scheme for identifying and tracking commercial vessels.

-- 25 SEP 09 / STSS DEMONSTRATORS -- A Delta 2 7920 booster was launched from Cape Canaveral to put two "Space Tracking & Surveillance System (STSS)" demonstrator spacecraft into orbit for the US Missile Defense Agency (MDA). The two spacecraft were designed to track missile launches and featured a datalink to allow them to perform cooperative observations.

-- 30 SEP 09 / SOYUZ TMA-16 (ISS) -- A Soyuz booster was launched from Baikonur to put the "Soyuz TMA-16" manned space capsule into orbit on an International Space Station (ISS) support mission, delivering two members of the ISS "Expedition 21" crew -- Maxim Suraev (first space flight) of Russia / RKA and Jeffrey Williams (third space flight) of NASA -- along with "space tourist" Guy Laliberte. Laliberte, the megarich founder of the famed Cirque du Soleil, was said to have paid $35 million USD for the trip.

The Soyuz capsule docked with the ISS Zvezda module on 2 October 2009. Laliberte returned to Earth on the Soyuz TMA-14 capsule, along with Gennady Padalka and Michael Barrett of the ISS Expedition 20 crew. Soyuz TMA-14 had been launched to the station on 26 March 2009; Padalka and Barrett had spent 199 continuous days in space, with Padalka's grand total running to 585 days in space.

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[WED 14 OCT 09] SELF-EMPOWERED

* SELF-EMPOWERED: As reported by SCIENTIFIC AMERICAN Online ("The Next Not-So-Big Thing: Nanogenerators" by Larry Greenemeier) considerable work is now being done on self-powered portable devices. The idea is far from new, self-winding watches being perfectly familiar during the era of mechanical watches, but it is becoming more relevant given the proliferation of modern gadgetry.

A research team at the Georgia Institute of Technology under Zhong Lin Wang of the School of Materials Science & Engineering has developed a scheme to harvest energy by converting low-frequency vibrations -- like simple body movements, the beating of the heart or movement of the wind -- into electricity using zinc oxide nanowires. The Georgia Tech work has been funded by the US military's Defense Advanced Research Projects Agency (DARPA), along with the Department of Energy, the National Institutes of Health, and the National Science Foundation.

The nanowires are "piezoelectric" -- they generate an electric current when subjected to mechanical stress. The group had originally focused on carbon nanotubes, but they proved troublesome, and so research switched to metal oxides, with zinc oxide proving the most attractive option. The nanowires are about a micron (millionth of a meter) long; they are fabricated standing in arrays with spacing of about a half-micron apart, on a flat gallium arsenide, sapphire, or a flexible polymer substrate, using a vapor-deposition technique. The tips of the array are capped by a tiny plate of silicon electrodes, with a wavy surface like that of corrugated cardboard. When the plate is pressed down, the flexing creates a voltage. Each nanowire only generates about 50 millivolts, which means they have to be connected in parallel to produce a meaningful energy supply. Wang's short-term goal is to produce a half a volt.

The Georgia Tech team sees the nanogenerators as providing nanowatts to microwatts of power, which is modest, but there are plenty of devices that get by on such power levels. Wang believes that, in production, the nanogenerators could be used to power implantable biosensors that can continuously monitor a patient's blood glucose level; autonomous strain sensors for structures such as bridges; or environmental sensors for detecting toxins. A lab demonstration is far from a practical device, however, the worst problem at present being that it is difficult to make the nanowires of uniform length so they mate up properly with the electrode plate.

* In related news, the tech blogs passed around a story about research startup named Levant Power, of Portland, Oregon, that has developed an automotive shock absorber that generates electricity from bumps and bounces on the road, scavenging energy that would otherwise just be thrown away as heat. The design team believes that their "GenShock" system can provide fuel savings of up to 10% in heavy trucks and off-road vehicles. They're pitching the idea to giant retailer Wal-Mart, claiming that the company could save over $13 million USD a year by adopting the scheme.

The GenShock shock absorber uses hydraulic fluid forced through lines into a centralized turbine module that drives a generator. The shock system is controlled by an active electronic system that also provides a smoother ride than conventional shock absorbers, reducing wear on the vehicle, as well as on passengers and payload. If the electronics fail, the GenShocks act like ordinary shock absorbers.

A heavy hauler with six GenShocks can produce one kilowatt per GenShock while on the road, enough to completely offset use of the alternator and even potentially enough to drive refrigeration or other accessories. The designers acknowledge that the scheme is probably too expensive, at least as it's currently implemented, for passenger autos, which don't load down their shocks heavily.

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[TUE 13 OCT 09] FLU FRENZY

* FLU FRENZY: As of early October, immunizations for the H1N1 "swine flu" were being performed across the USA, beginning with a batch of 600,000 doses of MedImmune's "FluMist" vaccine, implemented as a nasal spray. The initial doses were targeted to high-risk individuals, including health care workers, children, and pregnant women. Pregnant women in particular are at risk from complications of the swine flu, with data from the US Centers for Disease Control (CDC) in August showing that 100 women had been hospitalized and 20 had died.

Polls show the US public is lukewarm to the vaccination campaign, but the state of New York mandated vaccination for all health care workers. Of course the US military is expected to mandate vaccination for the troops; there was an outbreak of swine flu on the assault transport USS BOXER during the summer, and by early October the Army had reported a death. There is also a protest campaign in progress against the vaccinations. As discussed here some months back, the anti-vaccination movement has been able to sow considerable doubt over the safety of vaccines, specifically claiming they cause childhood autism, though no careful studies have supported that claim.

Public health authorities have reason to be worried about swine flu. The infamous flu pandemic of 1918 -- discussed here in 2007 -- started out mild, with an initial wave of infections in the that was not much more than an inconvenience. A few months later it mutated into something hideously virulent, killing tens of millions all over the globe. Given this horror, the push for vaccination is not surprising.

However, the current vaccination campaign is dogged by an unfortunate precedent. There was a swine flu outbreak at Fort Dix, New Jersey, in 1976, leading to a massive prevention campaign in which 48 million Americans were vaccinated. It was a fiasco. All vaccine programs have a certain rate of bad reactions; unfortunately, the rate with the 1976 program was very high, with 25 people dying from the vaccine. That might have been forgiven had there been a deadly flu outbreak, but the disease never spread beyond Fort Dix and a few other localities, fading out quickly. The vaccine was more lethal than the disease.

Is the 2009 swine flu another false alarm? That's clearly not the case: the swine flu this time is widespread and has been gaining momentum for months. As of 1 September, over 2,000 people had died of swine flu around the world. Still, given the unfortunate history of the 1976 campaign and the current agitation against vaccines in general, the resistance is no surprise.

Antivaccine critics have worried that the flu vaccine has been rushed into production with inadequate testing. Actually, since new flu strains appear every year, new flu vaccines are produced every year anyway, and dealing with a new strain is more or less routine. There is nothing entirely new about the swine flu vaccine, and the track record of safety for flu vaccines in previous years is good. There is no specific basis for simply assuming the new vaccine is unsafe, though of course public health officials are keeping an eye on the vaccination campaign. Vaccination does always present a risk; but a virulent disease poses a much greater one.

The fears persist and are exaggerated over the internet. Vague reports suggest that the lunatic fringe is playing up the vaccination program as a sinister conspiracy orchestrated by the Obama Administration, no doubt with various evil ends in mine. There was even a tale of a swine flu vaccination turning a recipient into the Incredible Hulk, though that sounds like a deliberate gag: "Puny humans never leave Hulk alone! Hulk SMASH puny humans!"

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[MON 12 OCT 09] NEW OPTIONS FOR HUMAN SPACEFLIGHT (3)

* NEW OPTIONS FOR HUMAN SPACEFLIGHT (3): After listing the options for future US efforts in manned spaceflight, the report of the Augustine committee then listed the options available to the Obama Administration. The first two options were constrained to the 2010 budget:

The other three envisioned raising the budget by $3 billion USD from fiscal 2010 to fiscal 2014, with a 2.4% inflation rise each year after that:

The committee was blunt in pointing out that the two options constrained to the 2010 budget effectively ruled out any significant human spaceflight effort -- raising the question of why a human spaceflight program would be funded at all. The committee's conclusion was that if the US is going to have a human spaceflight program, it will need the indicated budget increase.

manned mission to Lagrange point

In sum, the committee concluded:

That concluded the executive summary report from the committee. A detailed report was in process at the time. [TO BE CONTINUED]

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[FRI 09 OCT 09] THE PARASITES (22)

* THE PARASITES (22): Parasitology is an unusually difficult field; the elaborate life-cycles of parasites are hard to examine and very hard to duplicate in the lab. Since parasites tend to be small and not easily preserved as fossils, their evolution is also poorly understood.

That they have evolved is not seriously disputed. Charles Darwin, in an effort to establish his bonafides as a naturalist, spent years investigating and cataloging barnacles, which proved to be an excellent test case for his concepts. Barnacles were obviously descendants of free-living shrimplike crustaceans that had taken up a sessile existence; the parasitic barnacle Sacculina had gone further and taking up a parasitic existence on other crustaceans, in the form of crabs.

Parasitism is a popular evolutionary strategy, being found in a wide range of organisms -- protozoans, flatworms, roundworms, arthropods -- with a wide range of adaptations to support the lifestyle. Studies of parasite genetics, morphology, and distribution -- both in terms of geographical distribution and distribution of related parasites in host species -- can provide clues to parasite evolution. One important feature is that, although parasites tend to become highly specialized to exploit particular niches in host species, parasites also have an inclination to jump from one species to another, exploiting new niches. Analyses of the evolutionary trees of parasites do not necessarily match the evolutionary trees of host species: the patterns of parasitism are more complicated than that.

* In any case, once a parasite has moved in on a host species, an arms race follows, with the host acquiring better defenses and the parasite acquiring better countermeasures. The battle between parasites and the immune system has been discussed, but the immune system is effectively the last-stand defense; a host is better off to keep the parasites out of its body in the first place. Some caterpillars, for example, are covered with spines to protect themselves from parasitic wasps, and ants have a range of tricks to protect themselves from phorid (humpback) parasitic flies.

A parasitic fly will stake out a trail left by foraging ants. When the fly sees an ant, it descends on it, jams an ovipositor in the vulnerable gap between the ant's head and its chitinous body, to then lay eggs. The eggs hatch into a larvae, which burrow into the ant's head and gradually devour it from the inside out, taking care to avoid the ant's tiny brain so the host will stay alive longer. In the end, the ant's head falls to the ground, where the larvae become pupae, using the discarded head as a cocoon. To protect themselves from such a gruesome fate, some species of ants will break into a run if they sense a fly about, or start thrashing about wildly and threateningly, clicking their mandibles open and shut threateningly. One species has acquired the trick of flipping its head over against its back, crushing the fly.

Leaf-cutter ants have acquired a particularly impressive defense against the fly. Leaf-cutter ants are common herbivores in Latin America, finding leaves that they take back to their colonies, shredding them and using them to grow fungus that the ants feed upon -- they can be thought of as something like insect mushroom farmers. The foraging ants are relatively large, but on the leaves they carry there are tiny sibling ants, known as "minums". Entomologists were long puzzled by the minums, wondering what function if any they served, but on investigation, it turned out that parasitic flies would light on a leaf, and then crawl down to the ant carrying the leaf. When the fly touched down, the minum promptly attacked it in turn, either driving it off or killing it.

The need to ward off parasites has influenced mammal evolution as well. Large mammals spend a considerable amount of time grooming themselves to rid themselves of parasites like ticks. In social animals, this is often a cooperative behavior, with mutual grooming not merely being healthy but also a seemingly comforting social interaction. One of the interesting little puzzles of human evolution is why, unlike nearly all other primates, humans are mostly bare-skinned; one particularly appealing suggestion is that, once humans were able to make clothes for themselves from animal furs or plant matter, fur became a liability, since it was such a good breeding ground for parasites.

Of course, some parasites have come up with tricks to defeat countermeasures such as grooming. For example, botflies are common pests of herbivores like horses; botflies may lay eggs in a horse's hair, with the horse swallowing them when it grooms. The eggs hatch in the horse's mouth and burrow down into the stomach lining, where they drink blood and mature. When they are ready, they release themselves and are excreted in horse droppings, emerging as adult flies. [TO BE CONTINUED]

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[THU 08 OCT 09] SCIENCE NOTES

* SCIENCE NOTES: The US National Aeronautics & Space Administration (NASA) put the Spitzer infrared space telescope into space in 2003, and since its launch it has returned a flood of infrared images of the cosmos. Sensitive infrared imagers have to be cooled, since it is impossible for the imager to pick up a target that is cooler than it is, and the Spitzer was cooled by liquid helium to about 4 degrees Kelvin. However, the cooling system gradually depleted itself, and the Spitzer finally ran out of helium coolant on 15 May 2009. Not to worry too much, however, since the spacecraft was designed with passive cooling systems that keep it at a still-chilly 30 degrees Kelvin; Spitzer remains in business, with NASA releasing spectacular imagery to show just how well the observatory works even without its coolant.

new Spitzer observations in Cygnus region

* The WIRED Online blogs passed on a report of a fascinating discovery in southern France of the fossil tracks left by a pterosaur -- flying reptile -- about 150 million years ago. The tracks show that the pterosaur touched down on its hind legs, skipped up into the air, then landed again, dragging its hind feet; it then leaned forward onto all fours and walked off. There are a number of sets of tracks at the site, but so far, none have clearly demonstrated how the reptiles took off.

* The WIRED Online blogs also had an interesting posting on the work of Harvard University biologist Aaron Ellison, who has been investigating the "micro-ecologies" inside "pitcher plants". These are carnivorous plants that live, as do other carnivorous plants, in boggy areas where nitrogen is scarce, and so they supplement their supply of nitrogen by trapping and consuming insects. The pitcher plants catch their prey using a juglike structure containing a pool into which insects fall and drown.

Over the last 15 years, Ellison and his colleague Nicholas Gotelli of the University of Vermont have been wading through New England bogs to investigate the plants, whose little pools are like lakes in miniature. Says Ellison: "You've got four or five trophic levels in a pitcher plant, just like you've got four or five trophic levels in a lake." At the base of the plant's micro-ecology are bacteria fed by the decaying insects, with the bacteria supporting plankton; which support single-celled animals; which support fly larvae. The fly larvae are the top-level predator in the micro-ecosystem.

The resemblance between the pitcher plant micro-ecology and the larger ecologies of lakes is surprisingly close. If a pitcher plant swallows up a swarm of insects, the result is "nutrient overloading", resulting in the degradation of a rich, multilevel ecosystem to an oxygen-starved and algae-dominated ecosystem. Nature provides elaboration over a vast range of scales, even in a world about the size of a shot glass.

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[WED 07 OCT 09] THE STING

* THE STING: The biology and evolution of venoms turns out to be a fascinating subject, and after poking around a bit I ran into an article from a few years back online from DISCOVER ("Stung" by Richard Conniff, June 2003) that discussed entomologist Justin Schmidt of the University of Arizona and the Southwestern Biological Institute.

Schmidt is not only an expert in the biology of insect stings, he also has extensive experience of being stung himself, having been stung by at least 150 different insects from all over the world, excluding the polar regions. He has compiled the "Schmidt Sting Pain Index (SSPI)", which rates stings from "1", a tiny spark -- as from a little sweat bee -- to "4 -- which is "don't try to stifle the scream" -- as from the tarantula hawk, which is a wasp that preys on tarantulas and has a sting that's like ramming a red-hot rusty nail into one's heel. Schmidt was once stung by a Brazilian bullet ant, which acquired its name from the fact that being stung by one is like being hit by a bullet, and rates it a "4+".

Evolution has provided stinging animals with an elegant toolkit of biochemicals that can tweak a target organism in a wide range of unpleasant ways. Venoms can attack cell membranes, disable neurons, turn the immune response into a weapon against its host, alter heart function, and even -- in some cases -- alter the victim's behavior to suit the interests of the stinger. The toxins carried by venoms are so capable that pharmaceutical companies have a great interest in them, since in low doses or with some alterations they can be used as medical treatments. Venoms can also kill. About 40 people die each year in the USA from insect stings, mostly due to allergic reactions to stings inflicted by the "hymenopterans" -- wasps, bees, ants.

The hymenopterans picked up the trick of stinging long ago, in the Jurassic period. The sting has its origins in reproduction. Female parasitic wasps have the notoriously ugly habit of depositing eggs onto a living host victim, most stereotypically a caterpillar, with the eggs hatching into larva that eat the host alive. It's not pretty, but humans can't complain since the wasps don't do it to us, instead helpfully targeting crop pests like tomato hornworms and cabbage loopers. Wasps have been playing this game for a long time and have acquired adaptations to do a more effective job of it. The female wasp uses its "ovipositor", a pointed extension of the abdomen, to lay an egg or eggs; some have ovipositors with a serrated tip to allow the wasp to penetrate the host and bury the offspring inside of it.

Obviously, hosts that object to such treatment tend to survive far better than those that don't. Eventually a lineage of wasps began to acquire biochemicals, deposited along with an egg through the ovipositor, that subdued the victim so it wouldn't fight back. Hymenopteran venoms evolved from there, with the ovipositor becoming a stinger; bees and ants, which descended from the wasps, still often retain stingers. A wasp fossil from Russia dated back 120 million years shows that stingers were well established by that time.

wasp

* Of course, if parasitic wasps benefit us by killing crop pests with their sting, we have paid for it to a degree by becoming targets of stings ourselves, most typically from honeybees, which ironically retain no trace of the parasitic lifestyle of their wasp forebears that produced in the stinger in the first place. The honeybee sting is not so severe -- Schmidt rates it a "2", like lighting a match, blowing it out, and then pressing it on your skin -- but it is significant because it is extremely well understood.

When a bee stings a victim, the barbs at the end of the stinger catch in the victim's flesh; the act of stinging rips out the bee's hind end, and it dies. It's not the most elegant of nature's constructions in that respect, but the stinger that is left behind is surprisingly active and capable. The stinger can go on injecting venom into a victim for up to 10 minutes; it also disperses an alarm pheromone that tells other bees: TARGET HERE COME STING IT! The sharp end of the stinger consists of a grooved tube, or "stylet", flanked by twin sharp blades called "lancets". Each lancet is serrated, with seven more barbs. The bulb on the other end of the stinger contains a neural cluster that causes the lancets to saw up and down in alteration, causing the stinger to dig deeper into the victim. The bulb also contains a venom sac and a pumping mechanism.

The sac contains about 600 micrograms of clear, colorless fluid. Most of that doesn't end up being injected, but even that small quantity of venom is devastatingly effective, containing about 40 different components optimized to inflict damage. Their target is the "cell membrane", the layer of proteins and fatty "phospholipids" that encase the victim's cells. The phospholipids are "polar" molecules with a "head" and "tail"; they form up two layers, one with the heads directed outward of the cell and the other with the heads directed inward, and the tails of the two layers facing each other.

The bee venom raises hell with the cell membrane. A peptide -- protein fragment -- wedges through the phospholipids on the outer surface of the cell membrane, allowing entry to an enzyme, "phospholipase A (PLA)", that decapitates the phospholipids, disconnecting heads from tails. The cell membrane breaks down. If the cell is a red blood cell, it gradually dissolves in a smear of hemoglobin; in contrast, a neuron tends to just keep firing pain signals over and over again.

A messenger molecule named "norepinehrine" and other components of the venom work to stifle blood circulation near the stinger, preventing the venom from being dissipated. That's why the skin around the bee sting turns white; the pain will persist for several minutes until the venom finally circulates away. In the meantime, a venom component named "hyaluronidase", referred to as a "spreading factor", attacks connective tissue to allow the PLA and other toxins in the venom to attack more targets. Spreading factors are common in snake and spider venoms as well.

The venom also contains chemical irritants, including "mast cell degranulating peptide (MCDP), which as its name implies attacks the "mast cells" in the skin. The mast cells are part of the immune system and trigger an immune response, resulting usually in swelling and redness. However, in rare cases the immune response is overwhelming and can kill the victim by allergic or "anaphylactic" shock in an hour, usually through suffocation when the windpipe swells shut. Even though such immune reactions in victims are rare, they are common enough to make the rest of us think twice before hassling a bee.

* Humans have, for good reason, learned to treat stinging insects with considerable respect, but Schmidt likes to point out that our attitudes toward them are inconsistent. Some species of harvester ants have venom as toxic than that of the most deadly snakes, but they are usually sold as the occupants of ant farms. They like to dig, they don't climb glassy surfaces well, they are hardy and easy to keep. They are small and unaggressive, not inclined to bite to begin with, and the dosages are so small that they don't present a serious threat.

Even the notorious "killer bees" that began to arrive in the US in the early 1990s are no major threat; dog bites kill many more people each year. So why the respect we give stinging insects? It's because their venoms are adapted to inflict pain even though they don't generally do that much damage. We tend to regard tiny creatures as harmless until they show they can deal those us a wallop all out of proportion to their size. That applies to predators as well, and so creatures like yellowjackets are colored brightly to tell those that might be tempted to eat them: BACK OFF. It works, and in fact there are insects that are actually harmless that mimic brightly colored stinging insects.

Still, predators can adapt as well, acquiring the ability to shrug off stings. Bears will raid beehives, protected somewhat by thick skin and fur. Capuchin monkeys like to make a meal of wasp larva and don't seem to mind the stings. Horned lizards gobble up highly venomous harvester ants without any concern. There is an evolutionary race between the stingers and the stung -- and unfortunately, the stingers are certain to come up with worse sooner or later.

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[TUE 06 OCT 09] E-WASTE CALAMITY

* E-WASTE CALAMITY: As discussed in an article from AAAS SCIENCE ("Confronting A Toxic Blowback From The Electronics Trade" by Richard Stone, 28 August 2009), environmental researchers from Hong Kong Baptist University were appalled when they visited the town of Guiyu in southern China. There they found a massive dump of "electronic waste" or "e-waste" -- made up of discarded computers and other electronics gear -- with the air foul from the stink of burned circuit boards, and the waters polluted with leachings from the material.

China has a bad reputation as a polluter, and e-waste is a big component of it, with one environmental researcher calling the problem there "monumental". China began accepting e-waste in the 1990s, but it quickly became troublesome, and so in 2000 the government banned its imports, with a recent law also imposing regulations on Chinese e-waste processors. Alas, as with so much else in China, laws that sound impressive on paper don't amount to much in practice. Electronic trash continues to be imported illegally, with China now handling 70% of the world's e-waste. It typically ends up in coastal villages where the residents use crude techniques to get traces of gold and other precious metals. At one village named Longtan, the runoff has colored a local stream a very beautiful shade of blue. The villagers do not bother with niceties like facemasks.

The toxic materials released from the e-waste gives environmental health researchers nightmares, with the list including carcinogens like dioxins and polycyclic aromatic hydrocarbons; neurotoxic heavy metals like lead; and other poisons like polybrominated diphenyl ethers (PBDEs). It is estimated that e-waste dumps tens of thousands of tonnes of PBDE in China each year. The soil in Guiyu has levels of PBDE thousands of times greater than the levels elsewhere, and the locals have concentrations of PDBE in their blood one to two orders of magnitude greater than normal.

Efforts are underway to figure out how to reduce the toxic impact of electronic gear and to monitor exports of e-waste, but the Chinese have the most to gain by taking action now. Stronger laws aren't needed; the laws are adequate as they stand, they're just not enforced. The difficulty is that local agencies don't have the resources or authority to do anything, and municipalities are too greedy to care about the long-range impact of e-waste handling. There is a push underway to try to convince the municipalities that the ultimate costs of cleanup will be far greater than the short-term profits, but it is always an uphill struggle to persuade people who see money in their pockets today that they may pay bitterly for their actions tomorrow.

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[MON 05 OCT 09] NEW OPTIONS FOR HUMAN SPACEFLIGHT (2)

* NEW OPTIONS FOR HUMAN SPACEFLIGHT (2): Although NASA's Constellation Program envisioned the Ares V as America's heavylift launcher, its development has barely got off the ground and the issue needs to be examined closely. The Augustine Committee felt that future manned spaceflight initiatives did require a heavylift booster, and that such a booster would also prove useful for defense applications. Current launchers can put a maximum of 25 tonnes into low Earth orbit; there's no strong consensus on how much payload a new heavylift booster will need to carry, but there is general agreement that it needs to be well more than 25 tonnes.

Under the Constellation program, the baseline assumption was that the Ares I would be able to put 25 tonnes into LEO while the Ares V would be able to lift 160 tonnes. For a Moon landing mission, Ares I would put an Orion capsule into orbit, which would then mate up with an Altair lander launched by an Ares V. The problem with this scenario is that it demands consecutive development of two different launch vehicles, inescapably resulting in a long delay to the date when the entire system will be ready for service.

Altair lunar lander

The Augustine committee considered a modified proposal that envisions development of a simpler "Ares V Lite", effectively an Ares V using available technology instead of improved main engines and larger SRBs, with a lift capacity of 140 tonnes. A human mission to the Moon would partition the functions between two Ares V Lite launches. Using a single launch vehicle would reduce operational cost and eliminate the consecutive delay. The committee judged the Ares V Lite to be the preferred baseline option.

Another option is to develop an expendable launch vehicle based on a relatively minimum modification of the shuttle -- a concept that has been around from the early days of the shuttle program and then known as "Shuttle-C". It would be cheaper and faster to develop, but it would only have a maximum lift capacity of 110 tonnes, and operational costs would be greater. The lighter payload capacity might be eventually offset by developing orbital refueling.

The last option is to leverage off the existing Evolved Expendable Launch Vehicle (EELV) boosters, the Delta 4 and Atlas 5. The potential lift capacity is only 75 tonnes, meaning a Moon landing mission would require twice as many launches. However, this option would make use of available hardware, and in itself would have the least cost and delay. It would mean that NASA would have to do things differently than in the past, in particular giving up much of the agency's internal work in booster development and handing it over to commercial firms, as well as developing procedures for orbital assembly of deep-space mission systems.

* As far as long-term goals beyond LEO went, the committee identified three main options:

A human mission to Mars is seen as the most significant goal in human deep-space exploration, but it is also technically very challenging, and the committee rejected the Mars First option.

The Moon First option would give technological and procedural experience to reduce the risk of Mars mission. In this scenario, short missions to perform scouting and validate technologies would lead either to a single relatively large Moon base or to a set of extended landings, for months at a time, at different locations on the Moon.

The Flexible Path option would similarly provide experience towards the Mars mission, and it would also help maintain public and professional interest in human spaceflight by providing a series of interesting missions. It would also accommodate changes in direction more easily than a fixed program. The committee described both the Moon First and Flexible Path options as "viable" and seemed to hint at a synthesis of the two, pointing out that Flexible Path could accommodate human Moon landings. [TO BE CONTINUED]

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[FRI 02 OCT 09] THE PARASITES (21)

* THE PARASITES (21): The Plasmodium parasite that causes malaria has come up with tricks to encourage a mosquito host to find humans to bite, allowing the parasite to connect to its second-stage host. A fluke named Leucochloridium paradoxum takes an alternate approach, coming up with tricks to make a snail host encourage birds to eat it, also allowing the parasite to connect to its second-stage host.

What makes this particularly fascinating is that the targeted birds don't like to eat snails, instead much preferring to feed on caterpillars. The fluke fools the birds by making the snail impersonate a caterpillar. The parasites migrate up the eyestalks of a snail host; the flukes, which have green or brown stripes, can be seen through the stalks and look like caterpillars. Birds eat them but get a load of parasites instead of a meal.

Similarly, tapeworms that infect three-spined stickleback fish require birds as their second-stage host, and so they change the color of the fish host to white or orange to make sure it attracts the attention of predators. The tapeworms also alter the fish so they are more buoyant, ensuring they stay near the surface of the water where birds can find them more easily, and seem to dull the usual caution of the fish so they are not so quick to dash away from threats.

The tapeworm Hymenolepis diminuta infects rats, with its eggs distributed in rat droppings. Beetles eat the droppings, with a small juvenile form of the tapeworm establishing itself in the insect host, which then needs to be eaten by a rat to complete the cycle. The tapeworm leaves little to chance in the process, the first trick being to change the scent of the egg-laden rat droppings so that they strongly attract beetles. Once set up in its beetle host, the tapeworm sterilizes it, ensuring that it is working for the parasite and not itself. Finally, the tapeworm makes the beetle very careless about concealing itself, increasing the odds that the beetle will be eaten by a rat, and also hobbles the ability of the beetle to fight back against a rat: the beetle has glands on its abdomen that eject a foul-tasting chemical to discourage predators, but the tapeworm makes sure the glands are shut down so the beetle tastes just fine.

* The Toxoplasma protozoan that often resides harmlessly in our brain is also capable of driving hosts to their doom, but fortunately it does so in rats, not us. When Toxoplasma infects a rat, its ultimate biological imperative is to get the rat eaten by a cat, the parasite's second-stage host. Rats normally get very nervous when they smell cat urine and usually avoid places marked by such smells. However, when infected by Toxoplasma the rats don't pay any mind to the smell of cat urine. Either the rats don't smell it any more or it doesn't cause them any distress, but the end result is the same: a rat with a greater chance of becoming dinner for a cat.

Toxoplasma, though it is generally benign to human hosts, seems to manipulate us as well, with men acquiring a more antisocial, don't-give-a-damn attitude, and women becoming more outgoing. These are relatively subtle changes, but they do seem to reflect a decrease in host's level of fear, which in the days when humans were more subject to predation, might well increase their chances of being eaten by a jungle cat.

Or maybe not. While some actions of parasites, such as making a snail resemble a caterpillar so it will be eaten by birds, are clearly elements of a biological strategy, in the case of Toxoplasma its alterations of the behavior of human hosts may be no more than insignificant side effects of the infection. There's a tendency to read "just so" stories into subtleties of parasite-host interactions, giving them a functional significance that they may not really have.

There is no specific design in the interaction, after all, it's just that spontaneous genetic variations alter a parasite to change its effects on a host, and those effects can be wide-ranging. If a particular effect makes the parasite more successful, increasing its ability to survive and produce another generation, gradually parasites that produce the effect will predominate. If there are other effects linked in that do nothing to either diminish or enhance the parasite's success, they will be carried along as well. The ghastly distortions of the human body associated by elephantiasis don't seem to do anything to help the filarial nematode worms that produce them. The worms are just making a living, and if they inflict misery on the host for no particular benefit to themselves while doing so -- that's just too bad for the host.

Humans, for good reasons, have a strong revulsion for parasites, and the idea that they that can manipulate our behavior makes them even more revolting, which is why the notion comes up so often in horror videos. The idea that parasites may manipulate us in purely haphazard and purposeless ways only adds to the disgust. Nature can be beautiful and inspiring to us, but the realm of the parasites shows us the dark side of the story. [TO BE CONTINUED]

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[THU 01 OCT 09] ANOTHER MONTH

* ANOTHER MONTH: I got myself into another sidetrack project this month. I have old archives of newsletters that aren't online and I decided to see if I could scavenge them for materials to create "retroactive" blog archives. That would give someone checking out the archives more to chew on, and also give more targets for Google searches.

I originally thought I could extend the archives back to 2000 or so, but the more I looked at it, the less sense it made. The materials in the archives had either been incorporated into the website or were out of date and stale. I only ended up adding two retroactive issues. It was still a substantial effort, since I folded quite a bit of material into some of the early blog archives, fleshing them out considerably. Now I have to go through the archives and proof them, particularly with an eye to adding hyperlinks from later articles to earlier ones. Adding the newsletter articles gives more targets for links and I believe they won't simply gather dust any more.

This has been a year for cleaning up such side projects -- they get to be a burdensome nuisance after a while. I just nailed down another one, having released a new revision of THE AMERICAN CIVIL WAR history with simple maps. That document doesn't get too much attention, I think it's just too big, and what attention it has received has mostly been from overseas. Since that means people whose knowledge of American geography isn't as good as hopefully might be expected for an American, I got requests for adding maps. So I cooked up almost 40 simple maps for the document. It took me months to work them out, maps being more labor than they look. I still need to proof them a bit, but they're uploaded and that job's effectively done.

* I'm picking up more legitimate followers on Twitter, and also getting more puzzled about Twitter spam. It's not that there's spam there and that it's obnoxious -- both of those observations being unremarkable -- but that the spam doesn't seem to make much sense on its own terms.

It can be tricky to figure out the games of spammers sometimes, but Twitterspam seems very ineffectual, with the number of Twitter accounts targeted running to a few thousand at most, more usually like a few hundred. It seems hard to believe that there would be any return on the investment of work, no matter how small it was, suggesting that Twitterspamming is an inept amateur spam activity along the lines of link exchanges.

More strangely I had a dozen or so women sign up all at once; I investigated and couldn't find any data or Tweets associated with them. They didn't look like sleaze queens so I wondered what the game was. I sat on them for a few days and then they all ran exactly the same Tweets, on hydrogen fuel cells. It looked like an attempt at a viral campaign, but it was hard to understand why they had to use a dozen fronts. If it had been one, I would have given it the benefit of the doubt and assumed it was legitimate, but handing me a dozen followers just made it more troublesome to block them all.

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