Slashdot Mirror

See also the article by John Cisar (a sceptic) An alternative interpretation of nanobacteria-induced biomineralization

Chameides, W.L., H. Yu, S.C. Liu, M. Bergin, X. Zhou, L. Mearns, G. Wang, C.S. Kiang, R.D. Saylor, C. Lio, Y. Huang, A. Steiner, and F. Giorgi, Case study of the effects of atmospheric aerosols and regional haze on agriculture: An opportunity to enhance crop yields in China through emission controls? Proceedings of the US National Academy of Sciences, 96:13626-13633, 1999.

The so-called "direct effect" of regional haze results in an approximately 5-30% reduction in the solar irradiance reaching some of China's most productive agricultural regions. Crop-response model simulations suggest an approximately 1:1 relationship between a percentage increase (decrease) in total surface solar irradiance and a percentage increase (decrease) in the yields of rice and wheat. Collectively, these calculations suggest that regional haze in China is currently depressing optimal yields of approximately 70% of the crops grown in China by at least 5-30%.

Chameides, W.L., H. Yu, S.C. Liu, M. Bergin, X. Zhou, L. Mearns, G. Wang, C.S. Kiang, R.D. Saylor, C. Lio, Y. Huang, A. Steiner, and F. Giorgi, Case study of the effects of atmospheric aerosols and regional haze on agriculture: An opportunity to enhance crop yields in China through emission controls? Proceedings of the US National Academy of Sciences, 96:13626-13633, 1999.

The so-called "direct effect" of regional haze results in an approximately 5-30% reduction in the solar irradiance reaching some of China's most productive agricultural regions. Crop-response model simulations suggest an approximately 1:1 relationship between a percentage increase (decrease) in total surface solar irradiance and a percentage increase (decrease) in the yields of rice and wheat. Collectively, these calculations suggest that regional haze in China is currently depressing optimal yields of approximately 70% of the crops grown in China by at least 5-30%.

Chameides, W.L., H. Yu, S.C. Liu, M. Bergin, X. Zhou, L. Mearns, G. Wang, C.S. Kiang, R.D. Saylor, C. Lio, Y. Huang, A. Steiner, and F. Giorgi, Case study of the effects of atmospheric aerosols and regional haze on agriculture: An opportunity to enhance crop yields in China through emission controls? Proceedings of the US National Academy of Sciences, 96:13626-13633, 1999.

The so-called "direct effect" of regional haze results in an approximately 5-30% reduction in the solar irradiance reaching some of China's most productive agricultural regions. Crop-response model simulations suggest an approximately 1:1 relationship between a percentage increase (decrease) in total surface solar irradiance and a percentage increase (decrease) in the yields of rice and wheat. Collectively, these calculations suggest that regional haze in China is currently depressing optimal yields of approximately 70% of the crops grown in China by at least 5-30%.

Chameides, W.L., H. Yu, S.C. Liu, M. Bergin, X. Zhou, L. Mearns, G. Wang, C.S. Kiang, R.D. Saylor, C. Lio, Y. Huang, A. Steiner, and F. Giorgi, Case study of the effects of atmospheric aerosols and regional haze on agriculture: An opportunity to enhance crop yields in China through emission controls? Proceedings of the US National Academy of Sciences, 96:13626-13633, 1999.

The so-called "direct effect" of regional haze results in an approximately 5-30% reduction in the solar irradiance reaching some of China's most productive agricultural regions. Crop-response model simulations suggest an approximately 1:1 relationship between a percentage increase (decrease) in total surface solar irradiance and a percentage increase (decrease) in the yields of rice and wheat. Collectively, these calculations suggest that regional haze in China is currently depressing optimal yields of approximately 70% of the crops grown in China by at least 5-30%.

Chameides, W.L., H. Yu, S.C. Liu, M. Bergin, X. Zhou, L. Mearns, G. Wang, C.S. Kiang, R.D. Saylor, C. Lio, Y. Huang, A. Steiner, and F. Giorgi, Case study of the effects of atmospheric aerosols and regional haze on agriculture: An opportunity to enhance crop yields in China through emission controls? Proceedings of the US National Academy of Sciences, 96:13626-13633, 1999.

The so-called "direct effect" of regional haze results in an approximately 5-30% reduction in the solar irradiance reaching some of China's most productive agricultural regions. Crop-response model simulations suggest an approximately 1:1 relationship between a percentage increase (decrease) in total surface solar irradiance and a percentage increase (decrease) in the yields of rice and wheat. Collectively, these calculations suggest that regional haze in China is currently depressing optimal yields of approximately 70% of the crops grown in China by at least 5-30%.

Chameides, W.L., H. Yu, S.C. Liu, M. Bergin, X. Zhou, L. Mearns, G. Wang, C.S. Kiang, R.D. Saylor, C. Lio, Y. Huang, A. Steiner, and F. Giorgi, Case study of the effects of atmospheric aerosols and regional haze on agriculture: An opportunity to enhance crop yields in China through emission controls? Proceedings of the US National Academy of Sciences, 96:13626-13633, 1999.

The so-called "direct effect" of regional haze results in an approximately 5-30% reduction in the solar irradiance reaching some of China's most productive agricultural regions. Crop-response model simulations suggest an approximately 1:1 relationship between a percentage increase (decrease) in total surface solar irradiance and a percentage increase (decrease) in the yields of rice and wheat. Collectively, these calculations suggest that regional haze in China is currently depressing optimal yields of approximately 70% of the crops grown in China by at least 5-30%.

Chameides, W.L., H. Yu, S.C. Liu, M. Bergin, X. Zhou, L. Mearns, G. Wang, C.S. Kiang, R.D. Saylor, C. Lio, Y. Huang, A. Steiner, and F. Giorgi, Case study of the effects of atmospheric aerosols and regional haze on agriculture: An opportunity to enhance crop yields in China through emission controls? Proceedings of the US National Academy of Sciences, 96:13626-13633, 1999.

The so-called "direct effect" of regional haze results in an approximately 5-30% reduction in the solar irradiance reaching some of China's most productive agricultural regions. Crop-response model simulations suggest an approximately 1:1 relationship between a percentage increase (decrease) in total surface solar irradiance and a percentage increase (decrease) in the yields of rice and wheat. Collectively, these calculations suggest that regional haze in China is currently depressing optimal yields of approximately 70% of the crops grown in China by at least 5-30%.

Chameides, W.L., H. Yu, S.C. Liu, M. Bergin, X. Zhou, L. Mearns, G. Wang, C.S. Kiang, R.D. Saylor, C. Lio, Y. Huang, A. Steiner, and F. Giorgi, Case study of the effects of atmospheric aerosols and regional haze on agriculture: An opportunity to enhance crop yields in China through emission controls? Proceedings of the US National Academy of Sciences, 96:13626-13633, 1999.

However, I have pieced together pretty good circumstantial evidence over the years for a flood in ancient times, just as described all over the world by people who had no (or very little) contact with each other.

About 11,400 years ago, we know from glacial core samples that the earth's mean temperature raised anywhere from 5-7 degrees in just a few decades (though some paleoclimatologists say as much as 10 degrees in just a few years). Before the glacial evidence, scientists believed that the temperature changed very slightly over a long period of time, a theory known as steady state earth which is increasingly being discarded in the paleoclimatological community.

Furthermore, as I said earlier, people all over the world have recounted stories of a great flood, the native americans had such a myth, the natives of the mid-atlantic ridge had such a myth, the natives of Australia had a myth, etc.

This global pervasiveness of the flood myth scientists have long explained as a "racial memory", with little or no evidence to support this assertion, because steady-state earth held that such things a global floods could not happen.

We now know that Earth goes through cataclysms periodically, such as the one which wiped out the dinosaurs, and that sometimes really scary global things happen. Scientists have yet to outright admit that there was a great flood, but have begund to tacitly admit it.

For example, we know for certain that before 11,400 years ago, the level of the ocean was 300-500 feet lower than it is today. Accepted wisdom holds that this changed gradually, but this theory may not last now that we know the mean temperature changed so drastically so rapidly.

Given the proclivity of humans to band around the coast, such a rapid rise would lead to massive casualties the likes of which are unknown to us today. It might indeed seem as though the whole earth flooded. Furthermore, quite interesting archaeological finds are likely to be buried underwater.

Well, here comes the circumstantial evidence I mentioned in the start of the post. Plato said that Atlantis sank about 9000 years before his time. It just so happens that he lived about 2400 years ago. Add up those two numbers, and you get 11,400.

It's quite a coincidence, and it's true.

There is a chain of mountains in the middle of the atlantic ocean called the "Mid-Atlantic-Ridge". If you examine a contour map, you'll see that if the sea were lowered about 300-500 feet, it would be a huge chunk of land, not quite as big as a continent, but not quite as small as what we call an island either.

To my knowledge, I am the only person to put this data together in this way. Those scientists who consider Atlantis to be a possibility place it in the mediteranean ocean.

I'm not saying there were telepathic pyramid building Atlanteans, but I think it is very possible Atlantis existed, and traces will be discovered under the ocean.

If you are tired of getting your information distilled for you by the news media and want more information ... take a look at a scientific paper on Lake Vida at The Proceedings of the National Academy of Sciences (PNAS) ...

http://www.pnas.org/cgi/content/full/100/1/26#B8

-Bill

No journal would publish something *just because* someone paid page charges -- it still has to be accepted by peer review -- page charges are just a way that some journals use to defray subscription cost (theoretically). For instance, I've had to pay page charges for my paper in the Proceedings of the National Academy of Sciences

Let's take the yeast protein interaction network as an example. This network describes the physical interaction of various proteins in that protein A binds to protein B and does something useful, like telling your mitochondria to make more energy. It turns out that some proteins interact with WAY more proteins than on average. In yeast some interact with >260 proteins while the average is around 3. For social networks, think of Kevin Bacon here.

Now, well add some complexity. Suppose you want to initially model a human disease in yeast. Now you have to find the networks that the human has in common with the yeastie. If this happens to include the proteins associated with the disease you would like to model, bang, you're in luck. Chances are that this small network will include a hub, but in my experience they are just hangers-on and not really related to the disease model.

Now back to social networks. Let's suppose you identify a collection of the population with some desireable relationship, let's say for example that you notice that a cluster of people tend to buy low-end luxury cars. You can annotate their small network with as much data as possible, where they went to school, what year, the cost of the houses they own, where they live, etc. This becomes a kernel from which you can find other social networks in other places. Now that you have this matching piece, who would you choose to give the wicked low discount on a BMW? You guessed it, the hub. More people would see her/him driving along beaming and glowing in a spanking new beamer. I can almost guarantee that this will happen at some point in the future. Currently the hub's are celeberities because they are 'seen' by more people, but it is kind of impersonal.

In any case, the main problem is that social networks are HUGE so much more complicated to search in this way. If you are interested, you can check out my paper in PNAS

Now if I could just find some investors for the social network side...

For the faunal extinction, I have physical evidence: fossils. Pollen levels are no substitute for copious amounts of plant fossils (i.e., leaf impressions, large lignite seams associated with short, quick deposition of plant matter).

I don't understand why you think that there would be large lignite seams. If the deposition happened fast enough, at the most there might be a few traces left in some places. It's not like there would be long term plant deposits. In any case, there is some indications of short term ones.

On the issue of faunal extinction immediately following a floral extinction, that is my point. You have said that one necessarily leads to the other. Where is your evidence?

Given that most dinosaurs either relied upon flora for their survival, or relied upon eating other dinosaurs which relied upon flora (and this is fairly well established, I think), what exactly are you asking for?
I don't need to know that if, for example, the world suffered enormous, nationwide crop failures, that people would starve. The food chain is pretty well established.
Guess I'm not sure what you're asking for, here. Proof that destruction of a food source on a massive scale tends to eliminate those species who rely on that food source?

I have fossils of dinosaurs.

So do I. So what? I tend to rely on the observations of people who do this for a living - and whose articles (and opposing ones) I've read for more than twenty years. Plus some field geology -

I'm an hours drive from the Badlands of South Dakota, where one can directly observe the K/T boundary. What's your point? I've hiked there (I don't take fossils from there out of respect, thank you, but I do and have reported my finds)

You have:

1) Meteor
2)?????
3) Profit!!!

Now that was exactly what I meant by trollish responses.

Oh, you also have your stomping of feet regarding my not providing links. I have run several queries of GeoREF for your evidence of large, global floral extictions and have found none.

Well, here's a couple links (I mostly rely on my personal library, but what the hell)

FLORAL TURNOVER AND CLIMATIC CHANGES ASSOCIATED WITH THE CRETACEOUS/PALEOGENE (K/T) BOUNDARY, NORTH DAKOTA, USA;

This one is also worth reading. I have many more. What I don't have is the time, nor the inclination, to post them.

I did, however, run a GeoRef search myself, and you're right. Using "K/T global flora extinction" I found very little. I suspect this is more a problem with my search terms, however, as running a Google search I found a lot more articles (not necessarily peer reviewed, but most were based on PR research). So I consider it likely that my search WRT to GeoRef was poorly worded. You might try different ones (assuming you have time). I don't.

--

Anyway, I'm sorry about the troll comment. This is an issue that I've been reading about since I saw the original Alvarez papers, and I'm thoroughly convinced. Disagreement tends to push my buttons :) and I'm busy enough that I tend to give short shrift to the arguments - not that I want to, it's just the way life is.

This is really interesting to me, but, like I said before, let's move it to my journal, or elsewhere (and you might want to google usenet, BTW), if you'd like to continue. I'd love to have something interesting to blog about there, other than slashdot stuff. In any case, this discussion on slashdot about this subject is completely irrelevant, and I'm sure you have better things to do (like writing more papers :)

This whole discussion reminds me somewhat of the debates about plate tectonics in the '60s :)

This will be my last post in this thread. Thanks for the discussion, but it's inappropriate to continue it here.

SB

Here is a nice Nature article on point.

To summarize: oil can definitely form non-biologically. However, chemical analysis indicates that most oil is formed biologically.

I unfortunately don't have time right now to sift through the UCLA paper linked to in the article, but note that the date of review is in 2002. This is not settled science, so it is very reasonable that schools would still be teaching the more established theory. (Granted, the idea coal or oil comes from animals rather than plants is silly. I hope very few people are actually teaching that.)

Also, if you're going to debunk theories, post links to reputable sites. Otherwise, it's hard to distinguish from the /. noise.

It's well known that mammalian brain size is clearly related to body size.

So - let's keep it simple, and look just within the primate family: Kevin Reader & Simon Laland did a study a few years ago of a comparative analysis of 533 instances of innovation, 445 observations of social learning & tool use, 607 episodes of tool use in primates.

This shows quite a clear relationship between primate brain size and social learning (& hence, complexity of social groups), in that, large brained primates innovate / learn from others / use tools more than small-brained primates.

The paper is available here: Social intelligence, innovation, and enhanced brain size in primates

Furthermore, a model is exactly what it is-- an approximation of your actual complex system. There would be some details that would be left out to simplify the model while keeping the interesting phenomena intact.

Using an actual system like the ping-pong experiment would still be an approximation to an actual avalanche but it provides a reasonably controllable situation and a level of detail that would be accessible to the investigators. And it generally would proceed much faster than simulating it in a computer.

We were in a similar situation in a research involving escape panic dynamics where the behaviour of agents (read: people) moving out of an enclosure were looked into. This would be akin to looking at the exit dynamics of people in a fire or in a football stadium in a a riot.

We did simulate escape panic but later on we used mice to look at the models in a real system. It turns out that the model reasonably gets some of the features of the dynamics but would miss out on things not explicitly included in the model, like herding behavior.

From the article it looks like they're trying to understand how a plant knows how many total pores to have open for breathing, given that each pore only has local information - there's no global sensor telling the pores what to do. They're also interested in why open pores are found in clusters.

A simple answer might involve the following:
(1) the pores are simple oscillators locally linked causing local synchrony. Groups of pores tend to be in sync, and the neighbors of the open group are induced to open because they're near the group. Therefore the pores tend to open near the open group, and close in the middle of the group. The result is travelling waves like a rock thrown in a pond. This type of idea was investigated I think first by Turing (of all people) in 1952 (for example)
(2) either the intrinsic period of each pore's oscillation or it's duty cycle (how long open compared to how long off) is modulated by the pore's detection of how much the plant needs to breathe locally. The result is oscillations all over the plant of openning and closing pores whose open times are modulated to solve the plant's total breathing needs.

Anyway, I don't see what's interesting about calling this computation. Air transmits sounds by local interactions of gas particles and the speed of transmission is modulated by density. But I don't see what is gained by claiming that the air is solving a computation to transmit sound at the right speed!

The reference I have is "Chains of Magnetite Crystals in the Meteorite ALH84001: Evidence of Biological Origin" published 2001 in "Proceedings of the National Acadamy of Sciences 98"

The paper is linked above, here's a quote from a space.com story on it:

The chains we discovered are of biological origin," said Dr. Imre Friedmann, an NRC senior research fellow at NASA's Ames Research Center in California's Silicon Valley and leader of the research team. "Such a chain of magnets outside an organism would immediately collapse into a clump due to magnetic forces," he said

Do you have a later reference that disputes this? It seemed pretty clear.

Phew, thank goodness someone else said it first. Here's links to a couple of articles about the active chromophore in the fish, vs. the active prion that causes BSE/vCJD. Good images in the flourescent protein article.

Repeat after me, everyone: Eating GM food will not cause my genes to be modified.

Here is "Origin of multidrug resistance in cells with and without multidrug resistance genes: Chromosome reassortments catalyzed by aneuploidy" which addresses the aneuploidy and "evolution" issues.

Thanks, that was exactly what I missed in the whole thing. So far, their claim to "retrodifferentiate" blood cells to pluripotent stem cells (= similar to embryonal stem cells in the 8-cell-stadium) is questionable. It seems they simply went for profit and propaganda rather than for proof-reading by the scientific community.

One (of many) more serious examples for (embryonal) stem cell research is given by D. Kaufman in PNAS 2001, 98(19), 10716-10721, for an online pdf version see Hematopoietic colony-forming cells derived from human embryonic stem cells.

Although enthusiastic about their results, the authors are honest enough to warn in the last paragraph of the article mentioned above:

The clinical promise of human ES cell-based therapies is great; however, because these therapies will be entirely novel, serious concerns about safety and efficacy will need to be addressed before human clinical trials can be initiated. The malignant transformation of cells that have been cultured for extended periods is a particular concern.

This has indeed been observed by Mathias Hoehn at the Max-Planck-Institute for Neurological Research in Cologne, Germany. As far as I remember, the researchers had caused an apoplectic stroke in rats. One week later, they injected the animals with embryonal stem cells from mice. MRT scans showed that the stem cells travelled through the rat brain right to the damaged region and started to differentiate and form a network. The stem cells, originating from different specimen, had replaced damaged tissue.

However, when the same stem cells (note: embryonal stem cells from mice) were used on mice, everything went out of control! Rather than moving to the damaged region, the stem cells started penetrating surrounding nerve cells and showed uncontrolled growth. In all mice examined, tumors were found!

Keeping that in mind, I prefer to take all "scientific" announcements in non-peer-reviewed journals with a ton of salt.

I work with femto-second lasers. I have used them in living cells for a variety of applications. Two of which involve destroying structures inside of living cells. Of course, these structures are placed into the cells by us (injection, knock-in, electroporation, etc). It's not an extremely new technique, it's just being used in a slightly new way. Some of the similar techniques are known as uncaging, FRAP, and more.

Personally, I rarely find anything that groundbreakingly new in Nature. Well, that's not exactly true. There is plenty of new data, and new applications and/or refinements of old techniques. There generally aren't wholly original techniques or completely new instruments discussed in that journal. My personal preference for that sort of thing are some physics journals.

One other thing, that may be of interest to /., semiconductor nanocrystals are starting to pop up in similar research. They are quite useful, if still hard to work with (they don't behave like most biological molecules). I got interested in quantum dots about a year ago, and have done a bit of work with them, but would like to do some more (when I find the time).

The study was biased as women (and left-handed men) were left out. Similar to the ducks.

The study was biased as women (and left-handed men) were left out. Similar to the ducks.

Wrong!

They're not really separated by miles -- they're doing this in a lab with a coil of fiber. Furthermore, what constitutes a measurement? Is it when the photons hit the polarizer? When they hit the detector? When the detector writes to the computer's hard drive? When a grad student analyzes the data?

These are not easy questions, and it will be some time before many of the issues are fully resolved.

As a side note, there are also people investigating the possibility that Bell is wrong. Two papers I've been meaning to read for a while are

• Bell's theorem and the problem of decidability between the views of Einstein and Bohr
• A possible loophole in the theorem of Bell

Wrong!

They're not really separated by miles -- they're doing this in a lab with a coil of fiber. Furthermore, what constitutes a measurement? Is it when the photons hit the polarizer? When they hit the detector? When the detector writes to the computer's hard drive? When a grad student analyzes the data?

These are not easy questions, and it will be some time before many of the issues are fully resolved.

As a side note, there are also people investigating the possibility that Bell is wrong. Two papers I've been meaning to read for a while are

• Bell's theorem and the problem of decidability between the views of Einstein and Bohr
• A possible loophole in the theorem of Bell

My apologies for so many subscription-required articles. Unfortunately, the biosciences are just like that. There have been some moves lately to make this less so, but large publishing companies like Elsevier and the Cell people and Science und Nature have been rather resistant. Hmmm, I wonder why.

Also, amphetamines and other stimulants don't calm people down. If anything, they stimulate them. But, one side effect of this stimulation is that it helps focus attention, which gets the kids to sit down, shut up, and pay attention.

Dear Scorilo - I hope and pray your father gets better.

> This very militantism makes me take the medical establishment counterclaims
> re: ozone with a grain of salt.
You made some good and balanced points. I just wanted to make sure you didn't miss the posting a little below this thread -- it links to this story on human antibodies producing ozone to attack bacteria and fungi. Maybe the autohemotherapy you wrote about earlier could help destroy cancer cells in a similar fashion?

The Science Daily story links to the abstract of the published research in the Proceedings of the National Academy of Sciences. It seems that publication date is 24 Feb - so you could try reading that issue of the Proceedings of the National Academy of Sciences in a University library, or try to contact the paper authors for more input.

Best wishes to your father and your family.

In this column, you'll find my comments on both the "Computer Made from DNA and Enzymes" article, published by National Geographic News and "New DNA Computer Functions sans Fuel" story provided by Scientific American. But more importantly, you'll find the real *meat*, the abstract of the research conducted by the scientists of the Weitzmann Institute of Science. It is published in today's online edition of the Proceedings of the National Academy of Sciences.

They actually implement a 2-state finite state automata with a two letter alphabet. The approach is basically something like the following. The 'hardware' is a restriction enzyme that is an offset cutter. The 'software' are pieces of DNA with 4-base DNA overhangs.
The transition table is essentially coded in the software DNA molecules. The current state of the machine and the current input symbol is coded for by a unique 4 base overhang. The software DNA has 4 base overhang to match a particular state, symbol. The software DNA binds to the input DNA, and then the restriction enzyme, since it is a 9-base offset cutter to the right, cuts the input to be in a new state. Something like the following:

Software
FFFFF??OOOO
fffff??

Input
nnnnn---
NNNNN---SSSS

F: FokI site
O: overhang
-: spacers
S: current state
N: next state
?: number of ? determines next state

Based on their model, the maximum number of states possible in the FSA appears to be dependent on the size of the offset for FokI and I think it's like 5 states. (Possible to have more states with larger offset cutter?) The maximum number of automata state and input symbol combinations, since they use a 4 base overhang appears to be 4^4. So it's not quite general enough to match any regular expression, and not even close to a read/write tape for a Turing machine, but is an interesting approach.

The abstract is available here. I've taken a look at the article since I have a subscription. The system implements a finite automaton, as opposed to Adleman's research which solved a much more complicated (NP-complete) problem. Also, the error rates are definitely too high to be useful at this point, but this is still intriguing research.

...is here . Quite terse, but what can you really expect when you've only got 6 pages?

As for the molecular biology aspects, the abstract states that they verified the existence of "112 previously unknown homologs of known proteins" , at least in some cases using RT_PCR (which suggests that the gene is real since it is expressed as mRNA). Apparently the "1019" refers to 907 additional predictions for which they have only computer-based speculations. Clearly it's nice to have some predictions to work from, but that's all this is.... wish I could supply more info but I can't get to the full text article without a subscription.

Anthrax is a complex of three proteins: anthrax protective antigen, edema factor, and lethal factor. Anthrax works by binding onto the surface of a cell, then an endogenous protease cleaves the protective antigen, which allows the lethal factor to enter the cell where it acts as a protease chopping up the cell's proteins (notably those involved with cellular signaling) which kills the cell. The authors of the above study have replaced the old cleavage site in the anthrax protective antigen with one that is recognized and specifically cut by urokinase, which is dramaticly upregulated in cells that are cancerous. The result is that the anthrax toxin binds cells but is only cleaved by urokinase, not by whatever was cutting it before. So cells that are making lots of urokinase (cancer cells) cut more of the anthrax protective antigen which allows more of the anthrax lethal factor to enter the cell and chop up more proteins, which kills the cell. The down side is that all cells produce some level of urokinase, so a few noncanerous cells will also be killed by the anthrax toxin, but this sounds like it could be less than traditional chemotherapy. Anyway, this is an incredibly slick idea for combating cancer!

no google html version.... : /

No, you are way off base. They are not trying to make pigs that genetically match individual humans. As a biology PhD, my understanding is that they are trying to engineer pigs whose organs will be less likely to be attacked as "alien" (leading to organ rejection) by human immune systems *in general*. This involves making multiple genetic changes in the pigs' DNA to make their genetic markers more compatible with humans'. This article is about a new method for making the genetic changes that may be quicker and less expensive... the technical details are in PNAS.

Perhaps the kinetic "experimental" 1.5 usec lag time is what is referred to in this PNAS article by Alan Fersht.

What the press release is skimming over is the fact that COX-2 and COX-3 are very similar. It was originally discovered as a *variant* of COX-2 that specifically responded to the same inhibitor (which are used in biochemistry as a marker for a particular enzyme) but had slightly different chemical properties (it binds acetominophen as well). See this paper from the same lab in 1999. So the logic is more like this:

1. We know that NSAIDs block COX-1 and COX-2, and this blockage is responsible for their analgesic activies.

2. Acetominophen blocks a variant of COX-2 (called COX-3) in much the same way that other NSAIDs block that class of enzymes.

3. Since COX-2 and COX-3 are chemically similar (possibly variants of the same gene), we presume they have similar functions.

Therefore, acetominophen acts as an analgesic because it blocks COX-3. It's not absolute proof (and undoubtedly they shall research it further!) but it is in fact very likely. In any case, this most recent study is only saying that COX-3 is found in human hearts and brains-- they're mainly trying to prove that the variant they discovered previously is actually found in vivo.

It's not like this is totally new, but it's not exactly old either. What the old stuff was about was calculations that showed that van der Waals forces could explain gecko's sticky feet.

This new stuff is a bit different. It's about experimental evidence suggesting that the van der Waals forces are actually responsible for the stickiness. If I remember the article exactly--in The Proceedings of the National Academy of Sciences?--they produced artificial gecko feet hairs that were sticky, and were sticky under various conditions that aren't explained by alternative theories.

So this is something new. Not a new theory, but new data.

For all those wondering why this subject suddenly returned to the limelight, it's due to a paper realased today in the Proceedings of the National Academy of Sciences (or pnas for those in the know).

Here's a link to the Autumn, et al. article, entitled "Evidence for van der Waals adhesion in gecko setae".

Human activity is now effecting the planet's ecology at levels never seen before NYTIMES: Forget Nature. Even Eden is Engineered..

The total world-wide human environmental footprint is now so large that we use up resources at a rate faster than the biosphere can regenerate. The original report at the PNAS is here (you need a subscription to read the entire text) Tracking the Ecological Overshoot of the human economy. The story was summarized in news papers about a month or so ago (sorry, can't find now) but the basic message is that overall we are annually using up 120% of what the earth can regenerate. The typical American is using up 22 acres of resources, topping the list by far. If everyone on the planet lived like an American, we would need a biosphere at least 5 times as large. For comparison, there are only 4.5 acres per person for use given our *current* population.

To learn more about sustainable living, check out Redifining Progress.

Glaciers and large meteors are also forces of nature and look what they have done. I personally can make choices and so can you. I'm in the process of a massive yet completely doable and non-ascetic lifestyle change by selling my oversized mansion of a house, moving onto a bus line and close to an in-city farmer's market. According to the Ecological Footprint Quiz at earthday.org, the differences between my old and new dwelling, my car vs. bus use and shopping habits will have me reduce my footprint from 33 (!!) acres to 14. (I probably still fly too much on airplanes).

the planes of atoms in the Martian magnetites are aligned with atomic planes in the carbonate in which the magnetites are embedded. This shows that the magnetites formed in the rock and not inside microorganisms

"In a reactor deep inside the Earth, one would expect fission products, having an average density about 60% that of actinides, to diffuse radially outward as the fuel reconcentrates radially inward because of gravity."

But at the center of the earth gravity is a much weaker force. I would guess that at the center of the earth, there would be no gravity, and the area around the center of the earth would have negligible gravity; sort of like how we see astronauts and satellites "floating" in orbit, but in reality most are in a slowly decaying orbit. The formula for calculating gravity & acceleration inside the earth is given at: http://www.syvum.com/physics/gravitation/gravitati on2.html, though even with these formulas my math skills are not sufficient for me to answer my one last question:

Is there a point just outside the center of the earth where gravity would actually pull you *UP*, since the bulk of the earth's mass lays above you? If so, then the denser fuel elements in this reactor would be pulled outward forming a layer enclosing it's byproducts in the center, rather then the opposite as they state in their theory.

Man, is this article bad.

Secondly, I'm pretty sure that a 5-mile ball would be over the critical mass/volume envelope for an uncontrolled chain reaction of the U-235 and U-233 present in uranium ore. The fact that the Earth hasn't exploded suggests that uranium is not concentrated into a ball. Anyone with the fast-neutron cross section data care to work this out?

As usual, the pop science publications do this little justice. The primary literature is published by the Proceedings of the National Academy of Sciences and is published online at: http://www.pnas.org/cgi/content/full/98/20/11085 and certainly makes the case sound more convincing.

The article at EV world doesn't didn't, to my dismay, discuss the electro-magnetic implications at all. It sounded like a stretch to me to conflate geomagnetism with a nuclear process.

I was a little disappointed the article didn't mention some of these more positive uses of the technology. There are some online journals that have gone one step further and granted free access to a list of third world countries (people who could really use the free information). There are some pretty high profile sites in there, too, like the BMJ Specialist Journals, The New England Journal of Medicine, and Proceedings of the National Acadamy of Sciences. I tried to find some press releases for those journals, but came up empty handed.

At least the introduction and some of the discussion is readable for a layman like me. People with paranoid ideas about non-ethical and safety-blind researchers would benefit reading some if this. To quote:

"The clinical promise of human ES cell-based therapies is great; however, because these therapies will be entirely novel, serious concerns about safety and efficacy will need to be addressed before human clinical trials can be initiated. The malignant transformation of cells that have been cultured for extended periods is a particular concern. "

At least the introduction and some of the discussion is readable for a layman like me. People with paranoid ideas about non-ethical and safety-blind researchers would benefit reading some if this. To quote:

"The clinical promise of human ES cell-based therapies is great; however, because these therapies will be entirely novel, serious concerns about safety and efficacy will need to be addressed before human clinical trials can be initiated. The malignant transformation of cells that have been cultured for extended periods is a particular concern. "