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Creating yet another challenge for global climate change modelers to consider, scientists report that the West Antarctic Ice Sheet is not thinning as previously believed, but is instead growing thicker. This finding, suggest Ian Joughin of the California Institute of Technology and Slawek Tulaczyk of the University of California--Santa Cruz, may indicate an end to the Holocene retreat of the region's Ross Ice Streams.

Although previously reported analyses of ice thickness indicate a long-term, ice-thinning trend, those results, the two scientists explain, were based on limited, in situ measurements of ice flow velocity. In contrast, Joughin and Tulaczyk's analysis takes advantage of the much-expanded database available from ice-flow velocity measurements obtained using Interferometric Synthetic Aperture Radar.

The new data, which provide the best assessment yet of the mass balance of the Ross Ice Streams, indicate the ice sheet is growing by 26.8 gigatons annually, in contrast to older estimates that there has been an ice mass shrinkage of 20.9 gigatons annually. The researchers say that stagnation of some of the region's ice stream flows is the primary contributor to the ice buildup.

There are, however, numerous uncertainties. Most notably, the ice flow in the region of the West Antarctic Ice Sheet is extremely complex, and the data that have been obtained so far do not suggest clearly how the ice sheet will evolve over the next few centuries. Although the thickening could in fact be a decadal-scale fluctuation, Joughin and Tulaczyk contend that current thermodynamic models and data suggest ice stream flow could continue to slow, and possibly even stagnate, leading to further ice buildup. (Science 2002, 295, 476-480).

I found the full paper here (that's http://pubs.acs.org/hotartcl/nalefd/nl015606f_rev. html for you paranoid types).

I was just thinking - they say their NOR gate is the size of approx. 1/100,000th the width of a human hair. Well, today's 1.4 GHz chips contain ~22 million transistors. That would make it 220 human hairs wide. That's a lot of power in a small space. I can't wait till the day I can crack RC5 on my cell phone.

Nano Letters, courtesy of the ACS.

There are many interesting articles there including one of the previous stories here regarding carbon nanotubes.

have fun..

http://www.acs.org/nsa/intcong.htm

Sure, not all the teams are using them - but many are, and this is sure to change the dynamics (if not the outcome) of the race.

We're talking 150% greater efficiency here, and at lower cost.

The photovoltaics is the interesting story - after all, we all could guess that many participants are using Linux and GPS!

Read this. The amount of coral used is very small, and the methods used for harvesting supposedly have little to no effect on the coral population.

It's such a small amount that they are using, it makes very little impact. Or at least so they say...

Scientists can already create structures that are similar to coral (at least in their porousity). An example of this would be Aerogels which have a similar structure.

A gel is formed, which contains a porous, solid network, and the liquid component is removed, leaving a hunk of material with an ultra-low density (comparable to that of air). Obviously this stuff couldn't be implanted into the body, but perhaps as our understanding of these processes increases we could create materials that are even more like coral.

It's definately worth doing, if you could create something like coral, only made out of aluminum, it'd be incredibly strong and incredibly light. It might also have some other interesting properties (if the tiny spaces inside were all the same size, there might be resonance effects, etc). Overall this really won't affect the coral population though, so we have nothing to worry. It'll be years till this is even common anyways.

Justin

Disclaimer: I study physics, not biology. I have a friend working on a project with kindey rejection and computer analyses of statistical correlations, however my knowlege of tissue rejection is rather limited.

there has been some very interesting work in the past few years with regard to polymer gels which change physical properties drastically in response to small changes in environmental conditions such as temperature, ph, light, electrical/magnetic fields, solvents, and others.

in some cases, these changes may be a thousand fold increase in volume, or a change in viscosity from fluid to near solid.

• Glue and PVA also work well.
• Another fun slime is made from 5 parts cornstarch to 1-2 parts water, by volume. This one is very slimy, but becomes rigid under abrupt pressure.
• From a chemistry teacher's standpoint, even hard-wheat flour (bread flour) is great stuff. Take bread flour, add water, and stir. Watch the lovely gluten threads intermingle as the starch becomes slimy. Add more water for more slime, or keep stirring for more gluten and bounce.

There have been some cool articles on polymers and slimes at Science News and ACS, but that hagfish was news to me. Oooooh!

• Glue and PVA also work well.
• Another fun slime is made from 5 parts cornstarch to 1-2 parts water, by volume. This one is very slimy, but becomes rigid under abrupt pressure.
• From a chemistry teacher's standpoint, even hard-wheat flour (bread flour) is great stuff. Take bread flour, add water, and stir. Watch the lovely gluten threads intermingle as the starch becomes slimy. Add more water for more slime, or keep stirring for more gluten and bounce.

There have been some cool articles on polymers and slimes at Science News and ACS, but that hagfish was news to me. Oooooh!

The American Chemistry Society has an article on the front page of Chemical & Engineering News titled Electrifying Plastics. It discusses the research which led to the Nobel prize for two chemists and a physicist, and laid the foundation for organic electronics. At the moment, the article is publically accessible. As a side note for Hemos, the cover story is on nanotechnology , and covers the issues in some detail a general form.

The American Chemistry Society has an article on the front page of Chemical & Engineering News titled Electrifying Plastics. It discusses the research which led to the Nobel prize for two chemists and a physicist, and laid the foundation for organic electronics. At the moment, the article is publically accessible. As a side note for Hemos, the cover story is on nanotechnology , and covers the issues in some detail a general form.

The American Chemistry Society has an article on the front page of Chemical & Engineering News titled Electrifying Plastics. It discusses the research which led to the Nobel prize for two chemists and a physicist, and laid the foundation for organic electronics. At the moment, the article is publically accessible. As a side note for Hemos, the cover story is on nanotechnology , and covers the issues in some detail a general form.

The important part about this is not the radiation moniker, but the EMF label. There are many enzymes in your body (this includes, for most people, their brain) that contain transition metals in their active sites. Moreover, these transition metals have magnetic moments which can be affected by a magnetic field. Therefore, important catalytic activities can be hindered by magnetic activation (or deactivation) of this metal.

Also, most of the molecules in your body that are biochemically interesting are chiral. This means that they have a configuration that for all intents and purposes reacts anisotropically to EM things like polarized light and magnetic fields. A quick search through the ACS publications will show you results of chiral molecules reacting preferentially in magnetic fields.

Mind you, this post doesn't endorse the notion that EMF fields cause cancer, but merely suggests possible mechanisms to the condition. Because, on the other hand, we live in a huge magnetic field everyday...the one produced by the planet we live on. (of course the local strength is probably smaller than the one made by the phone next to your head-or nads if you use the ear/mic attachment and keep it in your pocket)

Maybe now it will be possible to create quantum computers that are much more functional than the ones that currently exist.

Not really. The problem with quantum computers is that essentially the computer is designed for a specific problem, since the physical structure of the computer IS the program. A diamond crystal may contain more atoms (and therefore more Qbits) but this doesn't necessarily make a more powerful computer, just like a heap of 1 billion transistors is not automatically more powerful than a P3, or even a 286 for that matter. It all depends on how they're wired together.

I expect a really powerful quantum computer would look more like a dendrimer, but that's just my guess.

I am one of the authors of the work that Geoff Ozins techniques are based on (Synthesis of Macroporous Minerals with Highly Ordered Three-Dimensional Arrays of Spheroidal Voids. Holland, B.T.; Blanford, C.F.; Stein, A. Science 1998, 281, 538-540 [Abstract] and Synthesis of highly ordered, three-dimensional, macroporous structures of amorphous or crystalline inorganic oxides, phosphates, and hybrid composites. Holland, B.T. et al. Chem. Mater. 1999, 11, 795-805 [Abstract]).

In addition to the technological limitations of photonic computing, we are a long way from fabricating these materials on a length scale that will work for even a rudimentary application, such as a waveguide. As the article states on the first page, their silica structure has "a typical single domain size of 100 um". The templates are brittle (they are essentially artificial opals) and the defect control is nearly impossible. Defects in the material grossly affect the behavior, that is, whether they behave like a photonic band gap material or a waveguide or whatever.

I think another promising route that isnt mentioned here is covered in Fabrication of photonic crystals for the visible spectrum by holographic lithography Nature 2000, 404, 53-56 [ Abstract. Free registration required]. Rather than using an opal for a template, they have complete control over the shape of the void lattice by the holographic interference of several lasers in a polymer matrix which is replaced by a high refractive-index semiconductor.

As a chemistry major at Rice University and a student affiliate of the American Chemical Society, I can tell you that we aren't up to anything sneaky. I swear on the little periodic table that I carry in my wallet!

As far as the different divisions go (American, European, etc.), the society strives to promote active fellowship between members by having regional and national meetings to share ideas and promote chemistry. Among the student affiliate chapters, one of the main goals is generating support and interest in chemical education from the elementary level to the college level.

Those of you in the San Francisco area might want to visit the ACS National Convention being held there the week of March 26th. You're likely to find more information on this new nano division there.

For more official information as to what the ACS is all about, visit this site.

As a chemistry major at Rice University and a student affiliate of the American Chemical Society, I can tell you that we aren't up to anything sneaky. I swear on the little periodic table that I carry in my wallet!

As far as the different divisions go (American, European, etc.), the society strives to promote active fellowship between members by having regional and national meetings to share ideas and promote chemistry. Among the student affiliate chapters, one of the main goals is generating support and interest in chemical education from the elementary level to the college level.

Those of you in the San Francisco area might want to visit the ACS National Convention being held there the week of March 26th. You're likely to find more information on this new nano division there.

For more official information as to what the ACS is all about, visit this site.

This whole agency seems just a bit suspicious -- according to their page, they've got a European division, even though they claim to be the American Chemical Society. There's nothing wrong with having a European division, of course, but why the name? Is there something that they're doing that they don't want us to know about? Just think about all the nefarious uses for nanotechnology, like a super-precise laser gun or a killer virus. The ACS's Spring news page seems to take credit for creating the Y2K bug; if they accomplished that without nanotechnology, who knows what they'll have in store for us next?

Just some food for thought. Thanks for your time.

Actually, this is pretty common. I worked for a lobbying organization for a while and "Government Affairs" is the polite term for "lobbying". So "Director of Federal Government Affairs" is really the polite way of saying "Head Lobbyist for Congress". Lots of big corporations and corporate special interest organizations have "Government Affairs" offices to watch out for their interests.

Shame you and I can't afford a "Government Affairs Director" to watch out for our interests, eh?