Just Science

Well, it’s a bit early yet, but jotting down a post here to remind (warn?) everyone that “Just Science” is going to try a second round the first week of February 2008.  Watch this space for updates!

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All the feeds are now off, aggregation has ceased! Thanks for everyone who participated & read. This site will be archiving these posts until next year’s Week of Science, when the whole mad week will begin anew.

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Being a green consumer is hard work, according to new research funded by the Economic and Social Research Council (ESRC). The study highlights a need for more practical help and incentives for green consumers, if we are to achieve a more sustainable society.

The University of Leeds-led study found that consumers who try to live a sustainable lifestyle have difficulty deciding which product to buy. "Consumers find that being green or ethical is a very hard, time consuming, and emotional experience," says Dr William Young. Apart from the usual issues such as price, reliability, and colour, they have the added complication of researching and weighing up all the environmental and ethical issues before purchasing a product, he explains.

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This week, we're talking about science. Or rather, since this is a Week of Science, I'm only reporting on the science gossip over by the water cooler. The development of a noninvasive test for fetal abnormalities. Here's Medscape's coverage, if you've got access. The new screening recommendations for Down syndrome, what causes Down syndrome (trisomy 21), and [...]

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Yes, Greg has nominated me for an award.... eeerr, meme! This is cool!

Here are the rules:
The original rules and the Template Meme exists here: Meme Index Case

1. If, and only if, you get tagged, win the prestigious award, write a post with links to 5 blogs that make you think. (Yes, you can link to >5 if you like)
   
2. Link to the index meme post so that people can easily find the exact origin of the meme,
3. Optional: Proudly display the ‘Thinking Blogger Award’ with a link to the post that you wrote.

Here are mine- in pseudo-random order...

Razib- the OG of thinkers, both at ScienceBlogs and GNXP
Shelly and her DNA genes at Retrospectacle
The Doctor- at Genetics and Health
The Frenchman at Seeds Aside
John Hawks

carry on people...

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OK, lets do a thought experiment.

1. You have a child that you love and adore
2. There are diseases, some of which are lethal.
3. Behavior influences the risk of contraction
4. There are 2 options
• Try (maybe unsuccessfully) to prevent risk-prone activities
• Provide vaccination that can prevent with 100% efficacy. This vaccine has few/no side effects...

Which strategy do you take? You could try and prevent the behaviors, BUT WHAT IF YOU FAIL? The disease is measles.... Of course, you vaccinate. Chicken Pox, vaccinate, rubella, vaccinate, HPV (and cervical cancer)- hold on, isn't that an STD??? Here are a few links to some stories on the controversy..

Parents decry mandating HPV vaccinations
Texas' HPV vaccination mandate: upon further reflection.
Should the HPV vaccine be mandatory?

Why does the specific behavior linked to disease (sex in this case) matter when choosing to protect or not? I for one, think it does not matter, and will argue that my 3 daughters receive it. (Kate, what do you think???)

If there was a vaccine that prevents HIV infection, would you say no to that one as well???

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Dixon imaging is a technique for separating out water and fat in an MR image that depends on the relative chemical shift between water and fat (as opposed to relying on the absolute resonance frequencies, as in saturation-based techniques).  For someone just getting started in this area, or who is simply interested, here is a list of references.  I am not attempting to be exhaustive.  In particular, I am not focusing strongly on clinical papers or more historical ones.

Dixon WT. Simple proton spectroscopic imaging. Radiology 1984;153(1):189-194.
As is often the case, reading the original paper is not strictly necessary for a full understanding of either the theory or practice of Dixon imaging.  However, this paper does describe in-phase and opposed-phase imaging and gives a good description of the basic idea. Also, it features a fairly entertaining selection of phantoms (an egg, margarine, and dish soap).

Ma J. Breath-hold water and fat imaging using a dual-echo two-point Dixon technique with an efficient and robust phase-correction algorithm. Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine 2004;52(2):415-419.
Reeder SB, Wen Z, Yu H, et al. Multicoil Dixon chemical species separation with an iterative least-squares estimation method. Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine 2004;51(1):35-45.
The two most prolific publishers in Dixon imaging are currently the groups of Jingfei Ma and Scott Reeder.  These two papers describe the basic approaches taken by each.  Both techniques have been licensed by GE-Healthcare as MEDAL and IDEAL, respectively.

Xiang QS, An L. Water-fat imaging with direct phase encoding. Journal of magnetic resonance imaging : JMRI 1997;7(6):1002-1015.
Although not as prolific, Xiang has also published several articles and his technique is in use at some sites.

Those four papers should prepare you for reading most current research in Dixon imaging.  At this point, you may decide you are more interested in reading about the clinical applications of Dixon imaging.  This list is particularly non-exhaustive–as a an example, I include no papers about the usefulness of the opposed phase image as a diagnostically useful tool in its own right.
Ma J, Choi H, Stafford RJ, Miller MJ. Silicone-specific imaging using an inversion-recovery-prepared fast three-point Dixon technique. Journal of magnetic resonance imaging : JMRI 2004;19(3):298-302.
Ma J, Singh SK, Kumar AJ, Leeds NE, Zhan J. T2-weighted spine imaging with a fast three-point dixon technique: comparison with chemical shift selective fat suppression. Journal of magnetic resonance imaging : JMRI 2004;20(6):1025-1029.
Ma J, Vu AT, Son JB, Choi H, Hazle JD. Fat-suppressed three-dimensional dual echo dixon technique for contrast agent enhanced MRI. Journal of magnetic resonance imaging.  2006;23(1):36-41.
Reeder SB, Markl M, Yu H, Hellinger JC, Herfkens RJ, Pelc NJ. Cardiac CINE imaging with IDEAL water-fat separation and steady-state free precession. Journal of magnetic resonance imaging : JMRI 2005;22(1):44-52.
Reeder SB, Pineda AR, Wen Z, et al. Iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL): application with fast spin-echo imaging. Magnetic resonance in medicine. 2005;54(3):636-644.

For a more detailed treatment about the theory and assumptions behind Dixon, the following paper is a must-read:
Glover GH. Multipoint Dixon technique for water and fat proton and susceptibility imaging. Journal of magnetic resonance imaging : JMRI 1991;1(5):521-530.

These papers give a little more technical development of some of the techniques mentioned:
An L, Xiang QS. Chemical shift imaging with spectrum modeling. Magnetic resonance in medicine. 2001;46(1):126-130.
Glover GH, Schneider E. Three-point Dixon technique for true water/fat decomposition with B0 inhomogeneity correction. Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine 1991;18(2):371-383.
Haacke EM, Patrick JL, Lenz GW, Parrish T. The Separation of Water and Lipid Components in the Presence of Field Inhomogeneities. Reviews of Magnetic Resonance in Medicine 1986;1(2):123-154.
Ma J, Singh SK, Kumar AJ, Leeds NE, Broemeling LD. Method for efficient fast spin echo Dixon imaging. Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine 2002;48(6):1021-1027.
Ma J, Son JB, Bankson JA, Stafford RJ, Choi H, Ragan D. A fast spin echo two-point Dixon technique and its combination with sensitivity encoding for efficient T2-weighted imaging. Magnetic resonance imaging 2005;23(10):977-982.
Pineda AR, Reeder SB, Wen Z, Pelc NJ. Cramâer-Rao bounds for three-point decomposition of water and fat. Magnetic resonance in medicine 2005;54(3):625-635.
Reeder SB, Hargreaves BA, Yu H, Brittain JH. Homodyne reconstruction and IDEAL water-fat decomposition. Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine 2005;54(3):586-593.
Szumowski J, Coshow WR, Li F, Quinn SF. Phase unwrapping in the three-point Dixon method for fat suppression MR imaging. Radiology 1994;192(2):555-561.
Coombs BD, Szumowski J, Coshow W. Two-point Dixon technique for water-fat signal decomposition with B0 inhomogeneity correction. Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine / Society of Magnetic Resonance in Medicine 1997;38(6):884-889.
Szumowski J, Coshow WR, Li F, Quinn SF. Phase unwrapping in the three-point Dixon method for fat suppression MR imaging. Radiology 1994;192(2):555-561.

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In side-by-side taste tests, pub-goers agree: “MIT Brew” tastes better than Budweiser — as long as tasters don’t learn beforehand that the secret ingredient is balsamic vinegar.

It sounds more like a fraternity prank than a psychology experiment, but the beer-guzzling participants in a recent study were doing their part for psychology. In this case, helping researchers determine just what it is about consumers’ knowledge of food products that af-fects their taste judgments.

Does Knowledge Of Food Products Affect Taste Judgment?

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...that marine fishes are so cool is the fact that they have a dispersive larval stage. Unbeknownst to most people is the fact that more than 99% of marine fish species have a dispersive larval stage. The larvae of marine fishes often look very different from the adults that we are accustomed to looking at, with some bordering on the very bizarre. The duration of this larval stage varies from species to species. Clownfishes have a pelagic larval stage that is often less than 5 days, while some puffer fish species spend up to a year as a pelagic larva. The morphological variation is equally fascinating. Leptocephalus larvae, which are the larvae of true eels, are able to absorb nutrients directly through their skin. Other larvae are equally bizarre. Just to introduce you to amazing world of marine fish larvae, here is one particularly amazing example (see photo).

This photo is of a Liopropoma mowbrayi, which is a cave bass that looks quite different as an adult. The extension of its first dorsal spine bears an uncanny resemblance to a siphonophore. Whether this feature serves to aid in protection, boyancy or both remains unclear. What is undeniable, however, is that the natural world remains a mysteriously amazing place.....

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Tonight's Advance Online Publication section of Nature Genetics contains a new study with an enormous author list (including three former colleagues of mine at Millennium) which surveys 238 oncogenic mutations in 1000 tumor samples from 17 types of cancer. This is a big study, but it should be kept in mind that this is the warm-up for grander schemes.

Alas, Nature Genetics isn't cheap & I don't have access to an electronic subscription, so I haven't read the paper. But from the Abstract, Tables & Figures (JavaScript link on the Abstract page), Supplementary Items and Nature Genetics' blog entry, one can get the gist of the story.

First, some foundation. It is important in this context to think of cancer as an evolutionary disease. Many cells acquire mutations, but only those that acquire mutations that lead to the loss of appropriate growth controls can lead to cancer. Fully progressing to a a tumor requires multiple mutations in almost certainly a stepwise fashion; the odds against all happening simultaneously are too high. Presumably one mutation gives the cell a small advantage & it proliferates. A second favorable mutation within that population leads to a new winner, which proliferates again. And so on, until a full fledged tumor arises -- and then it continues further to select for more and more aggressive variants. Chemotherapy or radiation therapy adds new selective pressures, which now enhance or reduce the fitness of various mutants. It is likely that at all times the tumor is really a population of cells with different genotypes, with constant selection for more 'fit' (i.e. more likely to kill the patient).

There are many mutations that can contribute to cancer, but this paper concentrated on point mutations which activate oncogenes. There are several reasons for this focus. First, high throughput technologies exist for screening point mutations whereas translocations can be complicated to screen (because their molecular details may be quite different between examples). Second, there tend to be a small number of possible activating mutations in oncogenes, whereas there are many ways to inactivate a tumor suppressor. The false negative rate (calling a gene normal function when it is fact abnormal) is therefore going to be much lower for oncogenes.

One focus of the paper is apparently searching for oncogenic mutations that either frequently co-occur or seem to be mutually exclusive. This is summarized in Figure 2. Why would you find such associations?

Frequently co-occuring mutations suggest that they are in some way cooperative. For example, if the tumor can result if two pathways are turned on, but not either one alone (a molecular AND gate), then an expectation is that mutations activating both pathways would frequently co-occur.

On the other hand, mutually exclusive oncogenic mutations would suggest participation in the same pathway -- if one is turned on, you don't need the other one two. For example, if they are in two branches which converge, and activation of either one will create a tumor (a molecular OR gate), then it is unlikely that both will occur. Another case would be for one mutation to be upstream of the other; if the effect of both mutations together is the same as either one alone in activating the pathway, then there would be no selective pressure for both.

Supplementary Figure 3 shows nicely how which gene is mutated strongly depends on the tumor type. This is a well-known phenomenon, but cannot be said to be well understood: why are specific tumor types so driven by particular mutations. In the tumor suppressor world it can be even more stark: why do mutations in BRCA1, which encodes a critical gene for proper DNA maintenance in every cell type, lead to tumors primarily in female reproductive tissues? This is a general phenomenon: there is a long list of tumor suppressors which have been discovered by very tissue-specific cancer syndromes yet are parts of central cellular machinery shared by all cells.

Supplementary Figure 4 gives an overview of how much of the cancers are explained, at least in part, by the mutations surveyed, and Figure 1 shows how much of each tumor is explained by each mutation. The 3D figure has some merits, but personally I would have tried to combine Figure 1 with supplementary figures 3 & 4 in one combined figure (3 might be a stretch, but S4 would fit nicely placed next to the gene axis).

For example, 100% of the pancreatic cancers surveyed had at least one mutation. Given that mutations in KRAS are very common in pancreatic cancer, this isn't totally surprising. 75% of polycythemia vera (PV), a leukemia-like condition were explained; if you go back to Supplementary Figure 3, the JAK2 column is all marked PV. This is a known association, and perhaps one of the more explainable ones (JAK2 is a key regulator of differentiation in the cell lineage that goes haywire in PV).

On the other end of the scale, only 1% of kidney or prostate cancer had a mutation. So in these tumors, something else is going on. In both cases, it is likely that mutations in tumor suppressors explain many of the cases; both tumor types are known to often be mutated in certain suppressors. There is also a big middle: 36% of breast, 50% of colorectal, 32% of lung, etc. Again, in some cases mutated tumor suppressors may be at least part of the story, but there may be other oncogenes unexamined by this study playing as well.

The future promises many more such studies. There are other technologies which can type many thousand point mutants at a time (though there may be other trade-offs; I'm not an expert on this). Ultimately, many investigators want to just sequence away; pilot studies have already been published (if you have a Science subscription, there is a nice letters firefight in the current issue on the topic). But that is a ways away; even with $1000 genomes, the mixed genetic nature of any tumor will make life challenging. But in the meantime, one can expect to see more studies such as this one, but with more mutations and more tumors. More mutations should help fill in the gaps, whereas more tumors would allow much deeper probing of co-occurring and mutually exclusive mutations, as well as detect rare mutation-tumor pairings (such as those listed in Table 1).

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In the past I’ve talked about Elastic Network Models (ENM) at bbgm. These can be looked at as a coarse grained scheme that allows scientists to look at motions in time scales beyond the traditional realm of atomistic molecular dynamics simulation. In fact, over the past few years, the trend towards multiscale simulations has increased significantly. This is partly due to the fact that increased compute power is making it possible to study larger systems at longer timescales, but also because it is becoming increasingly necessary to approach a problem from multiple directions. Multiscale modeling can be simplified into the following scheme (in length scale)

Electrons (Quantum mechanics) –> Atoms (Molecular mechanics) —> Segments/Reduced representations (Coarse grained/Mesoscale) –> Continuum/Bulk (Continuum dynamics/Finite element methods).

In addition to the length scale, these are also fairly representative of the addressable time scale (fs –> ns –> ms –> higher respectively) In this post, I will talk about the move towards addressing longer time scales and larger systems using various coarse graining techniques.

Normal mode analysis (NMA) is a common way of trying to look at longer timescale vibrational motions in molecular systems, e.g. proteins. However, NMA is computationally expensive, which limits the sizes of the systems to which it is applicable and the number of modes that can realistically be calculated. Qiang Cui and others have developed Block Normal Mode methods which use a sparser Hessian and can be applied to larger systems which provide some computational advantages. Personally I think BNM type approaches might be very relevant to the sort of MM-PBSA methods described in the previous article. However to study large scale cooperative motions ENM is probably the best method that I know of.

One of the problems that began to interest me a couple of years ago were ways that people were using to take results from atomistic simulations, usually MD simulations of biomolecules or polymers and transfer that information into coarse-grained models that could be used to study molecular machinery and look at mechanical properties of biomolecular system. Much of that interest came after listening to a talk by Greg Voth. Protocols to go from quantum mechanical representations of model systems and transfer those parameters to classical molecular mechanics force fields have been fairly well established for a while now. On the other hand, the jump from molecular systems to the kinds of coarse graining schemes used to represent more macroscopic motions and properties are relatively less well understood, especially for biomolecular systems. Mesoscale approaches for polymer mixes have been used for a while, but are still a work in progress (Disclaimer: I was actively involved in this area towards the end of my stay at Accelrys and some of the most knowledgeable people in the field still work there). For biomolecules the systems create their own challenges and a chunk of the community is actively looking at this problem.

One of the key challenges in any such coarse-graining scheme is the need to retain as much information content as possible without losing the advantages that coarse-graining brings. The general approach is to reduce the system into some coarse-grained representation and then represented the forces between the reduced segments in a meaningful way. Much of the challenges lie in part two. What I learnt from Voth’s talk and subsequently from reading his papers was the lack of information content in most methods in place. The other thing that started becoming apparent was how difficult generalizing CG potentials was, if at all. Voth’s approach to coarse graining is a method he calls Multiscale Coarse-Graining (MS-CG), which is used to systematically derive a coarse-grained potential from atomistic-level interactions.

The method used by Voth is called force matching, a method that was developed for condensed-phase systems. The system uses a trajectory to derive a pairwise effective forcefield. The method is agnostic of how the trajectory is generated, the most common method being atomistic MD trajectories. I won’t go into the detailed derivation here, but here are some of the features that jumped out at me

(a) The authors fit their CG force field to a number of shorter system MD trajectories and average over those. Previous techniques used whole trajectories
(b) CG sites are associated with the CM of the underlying atomic groups. Applying the FM procedure to these data yields the effective interaction between the CG sites as it is present in the underlying atomistic simulation. This is not a mandatory selection. The geometrical center could also be chosen as can a hybrid approach.

A lot of the work on multiscale biomolecular simulations has been done on lipids, vesicle formation, etc. To generate the FM data, MD simulations in explicit solvent (TIP3P) are carried out (in the original paper at least), and the Particle Mesh Ewald (PME) method was chosen to model long range electrostatics. This system was then coarse-grained (using the center of mass approach) and the force matching procedure was applied to 4000 configurations from a 40 ps trajectory (which is fairly short). The authors found that their approach was able to reproduce the structural properties of the lipid bilayer quite accurately, and the input data is not any different from a typical MD simulation. For more complex systems, one might need to be more creative about the CG procedure. Automation of any such procedure would be a must for large scale application as well.

This is of course not the only method. Work by Julian Shillcock, Mikko Kartunnen, Qiang Cui, Aatto Laaksonen, etc should also be considered, but I have always found Voth’s approach to be the most elegant.

Thus ends the formal part of Just Science week. As Arunn has mentioned, blogging about pure science is a lot harder than it sounds.  I found a lot of great science blogs though and got a lot of traffic this week, so at least a few people are interested in biomolecular simulation and protein structure prediction.  Now .. back to our usually scheduled programming.

Further Reading:
Multiscale modeling of MscL

Technorati Tags: Just Science Week, Multiscale Modeling, Greg Voth, Biomolecular Simulation, Molecular Modeling

Filed under: Life Science, Commentary, Computing, Physical Science, Review, Modeling & Simulation
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I’ve been jumping around different subjects these last days mainly because I have a fair amount of interest in most of the areas involved. This time I’m going to talk about the Ouchterlony double immuno diffusion simulator I found a couple of months ago.

Yep, Immunology is a field that I have high interest in and there just seems to be so much still to be discovered.

For those that don’t know what Ouchterlony double immuno diffusion is, here’s a quick definition:

A technique designed to establish the identity of unknown protein samples based on the interaction between antibodies and antigens in solution. Anti-serum, antigens, and/or an unknown substance are each placed into separate wells and allowed to diffuse radially outward through an agarose gel.
As the expanding rings come in contact with each other, insoluble antigen/antibody complexes precipitate out of solution forming readily recognizable patterns. (in Alzforum.org)

OK, so getting back to the simulator, I’ve found it to be a great tool to understand how this technique works. And it’s obviously less time consuming and less expensive.

More information on Ouchterlony can be found here:
http://www.edvotek.com/pdfs/270.pdf
http://en.wikipedia.org/wiki/Ouchterlony_double_immuno_diffusion
http://www.snv.jussieu.fr/bmedia/ATP/immu2.htm (in French but VERY COMPLETE)

Technorati Tags: Ouchterlony, Immunology, Double Diffusion, Simulator, Proteins, Antigen, Antibody, Science

Filed under: Science, general, Biotechnology, Academia, WWW, immunology
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Every once in while, I read something on the internet that boils my blood. Last year it was the utter nonsense coming from the beauty industry about the benefits of deep-sea water (Which won me a Fuzzy). Now it is ramblings from Nick Szabo. Who is Szabo?

Nicholas Szabo holds a Juris Doctor degree from The George Washington University and a Bachelor's degree in computer science from the University of Washington. He has substantial experience in the areas of Internet security, e-commerce, and software engineering, and is widely read in history, economics, and science.

Apparently, all this education has convinced Nick that peak oil is nonsense and deep-sea deposits will sustain us for years.

Peak oil is based on the Hubbert peak theory. Basically it states that single oil field is finite and thus production from that field will follow a normal curve, with production peaking and eventually dwindling due to resource depletion. Oil companies to predict future yields use this theory routinely.

This theory has been extended to predict a global peak for all oil reserves. Hubbert himself accurately predicted the peak for U.S. oil (late 1970's) in 1956. He predicted a global peak sometime around now. There are alternative models that largely make the same predictions. Have we already hit peak? Several advocates and members of industry think so. Of course, all this generates controversy and criticism. Most of the criticism centers on pointing to inability of the model to predict a definite year (e.g., we have passed many of the previous prediction dates). Irregardless of whether the peak is 1999, 2003, 2006, 2010, 2021, there seems to be little evidence that there will not be a depletion of oil in our lifetime.

So what does Szabo say?

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I’ve been a good boy all week. I’ve kept my skewed perspective all to myself and not imposed it on anyone since I was being mr-serious-astronomer-guy spewing forth astronomical information for the nobly named Just Science Week.

The thing is, I didn’t want to distract you. I wanted you to learn this stuff, because you must learn it. It is your responsibility as a human being to know as much about your universe as you can.

Why? Because that’s what separates you from the monkeys. You are not a monkey, you are a critically thinking human being capable of imagining and comprehending a great many things.

Wondering about what the universe is made of and how it works should come naturally to you. If it doesn’t then you’re either brain-damaged, distracted, stressed-out or you really, really just don’t give a sh*t. All of the above reasons could be forgiven I guess, but if it’s the latter then I spoke too soon when I said you weren’t a monkey.

I know that’s harsh, but think about it for a minute. What we know defines us. The thoughts that we have in our heads, along with our emotions, make us who we are. We make choices every day based on our experiences and our memories and our knowledge. The sum total of these choices ultimately craft the quality of our lives. We should always strive to make the best choices we can. To the extent we can do that, we improve our own lives and every other life on the planet.

Monkeys don’t make choices, they react to their environment, they adapt, they alter their behavior based on what their environment does TO them or what it provides FOR them. Monkeys don’t plan, create, or grow emotionally (at least as far as I know).

You are not a monkey, yet an embarrassing number of people live like they are. They react, adapt and alter their behavior based on what life throws at them instead of thinking and choosing something different, better.

I don’t mean to be hard on monkeys and I’ll cut them some slack now, but I’m trying to make a point. Of all the creatures on the planet, we humans, whether we deserve it or not, are at the pinnacle of life on this planet. We got here because we were curious. We’re in charge, and we can’t stop being curious now just because the rent’s due or Brad thought Angelina was hotter than Jennifer (definitely way hotter BTW).

So, I beg you, don’t deny your natural curiosity about the universe we live in. Don’t let life get in your way. The more you take the time to learn about how the universe began, how old it is, what it’s made of, how big it is, how fast it’s accelerating, and what we still need to learn about it will pay huge dividends in your life in the future.

How?

The choices you make in your life will be made through the lens of your knowledge and your emotions about that knowledge. The effect of these choices become your life experiences and they intimately color your life.

Increased knowledge gives you the tools to make smarter choices, choices that change your life such that the rent’s easier to pay, that girl is easier to get in to bed, and the kids aren’t such a pain. The more you know, the more you are capable of. The better human being you become.

Do something everyday that puts you a little outside of your comfort zone, makes you squirm in your skin (Oh my God, I can’t believe i did that!). Doing so will shift the thoughts in your head a little bit everyday, causing new synapses in your brain to connect, making your brain smarter, making you a slightly better (evolved) human than you were moments ago. These new thoughts will alter your emotional state, changing the choices you make.

Which changes your life.

Technorati Tags: cosmology, Just Science Week

Filed under: cosmology, dont' make me use the spank ray, i am not a monkey
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Science week is over and I have managed to do 50% of what I promised. I have my post on string theory half written but couldn’t finish it as I got held up in other stuff. Science week was fun. It helped me convince myself that I can continue regretting my decision to quit Physics. It also got me started on writing about science whenever time permits. I have kept a target of atleast ten long posts on science every year. I will be posting on my Science Blog (started several months back on the suggestion of Arunn to write about science but never got a chance to get to it) whenever I have time. Science blogging is difficult. You need to spend quite a lot of time. In my politics blog, I could post anything without even reading once before I click publish button. I could manage some 2-5 posts on that topic everyday. But science blog needs heavy concentration and lot of time. So whenever I manage to get that time, I will post it on my Science Blog. Thanks to Science Week for kickstarting me on science blogging. I will try my best to post atleast once in that blog. I am still sick (reason for not completing the string theory post) and I hope to recover by tuesday so that I can attend Ignite Seattle meeting. I am also hoping to start my regular whines about political topics from tomorrow.

Filed under: Science Week
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Fermions tend to avoid each other and cannot "travel" in close proximity. Demonstrated by a team at the Institut d'optique (CNRS/Université Paris 11, Orsay-Palaiseau), this result is described in detail in the January 25, 2007 issue of Nature. It marks a major advance in our understanding of phenomena at a quantum scale.

For many years, the theory of quantum mechanics stipulated that certain particles, the fermions(1), were incapable of "travelling" in close proximity. For example, in a jet of identical particles, the theory supposed that the distance between them was always greater than a given value, called the "correlation length".

The vacuum system containing the source and atom detector which enabled observation of the anti-bunching of fermions and the bunching of bosons. This photo shows Martijn Schellekens and Valentina Krachmalnicoff, two doctoral students who worked on the experiment. (Image copyright CNRS)

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When we talk about conserving fish stocks what do we mean? I see conservation as allowing fish to maintain healthy viable populatoons so we can maintain long-term sustainable harvest. Overfishing is the enemy not fishing.  Often someone tries to convince the public that you have fisherman on one side and environmentalist on the other.  Thanks media! But in reality the priorities are not so different , or should not be.  Successful management of fishery means jobs in the long run.

The days of mom and pop fisherman are long over and replaced by international conglomerates with business models for short term profits. Just like small farmers and small business owners. But then there is the media, bringing out Joe Shmo fisherman. He's salty and skipper and has 12 children to feed.

But skipper Mariano Lopez, gazing at this mound of exuberance on his trawler's deck, is disappointed. Like many patches of the Mediterranean, this overworked fishing ground is not yielding the bounty it once did. "There should be twice as much," Lopez says, shaking his head...

Everytime someone steps in to prevent overfishing , this case EU, somebody complains about destroying 'tradition' and 'livelihood'. What part of no more fish equals no more jobs is difficult to grasp?

The money quote from the article is this...

In the 1980s, Canadian fishermen scoffed at scientific warnings that stocks were diminishing even though they could see for themselves that the fish were getting smaller--a key indicator of overfishing. "All of a sudden they had to say: 'Oh no, there are none left,'" said Vallette.

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Filed under: Conservation
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What does 78.1 million U.S. dollars buy you? Presidential election? A month's supply of prescription medication? Health care? A house in California?

Definitely not enough money for any of those. What it does buy is a shiney new ship from fine Norwegian shipbuilders and a visit from royalty.  Who else are you going to have build a ship?  NERC (National Environmental Research Council, UK) and the National Oceanography Centre recently welcomed thier new addittion to the family.  The RSS James Cook will see her first expedition to the Mid-Atlantic Ridge.

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We've all heard of Mad Cow disease (bovine spongiform encephaly) in the media. A few years back it was as big a sensation as bird flu and twice as scary. The colloquial understanding of the disease was poor: what it was, how humans (or cows) could get it, what should be done to curb its spread, and whether or not there was any treatment. This disinformation led to small-scale hysteria when it came to beef, with some countries (eg Japan) completely banning all beef from nations that were even suspected of having a "mad cow." The beef industry as a whole took a hit, as pubic perception held that beef was now diseased, and could cause them to become demented or crazy.

Scientists rapidly discovered that "Mad Cow Disease" and its human counter-part Creutzfeld-Jacob's Disease was caused not by traditional pathogens such as a virus or bacteria, but something as simple as a protein. Admittedly, this protein---called a prion---is actually anything *but* simple and studying prion diseases has been dangerous and slow to bear fruit. However, it is fascinating that a conformational change in a protein can wreak such havoc on the brain, quickly rendering it as porous as a sponge and its owner gradually more incapacitated.

(Continued below the fold.....)

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National Journal has released a new “Congressional Insiders Poll,” which surveyed 113 members of Congress. Only 13 percent of congressional Republicans say they believe that human activity is causing global warming, compared to 94 percent of congressional Democrats.

What a bunch of nut-jobs huh..
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Egon just alerted me to the new molecule displays on the Chemical Blogspace front page. Tagged molecules now show up in a special area and link back to the relevant blog posts and additional information about the substances.

This is a particularly elegant way to evolve a bit more towards a semantically aware chemical web because it requires so little from the author. Just add a few simple tags.

The UsefulChem group should recognize a few (all too) familiar molecules on the page, such as these:

InChI=1/C7H12N2O/c1-8-2-3-9-4-6-10-7-5-9/h2-7H2
2-morpholinoethyl isonitrile

InChI=1/C8H8O/c9-7-6-8-4-2-1-3-5-8/h1-5,7H,6H2
phenylacetaldehyde

InChI=1/C8H6O3/c9-4-6-1-2-7-8(3-6)11-5-10-7/h1-4H,5H2
piperonal

InChI=1/C7H6O3/c8-4-5-1-2-6(9)7(10)3-5/h1-4,9-10H
3,4-dihydroxybenzaldehyde

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By way of a final post for the week of science challenge, I have decided to review my previous six posts. Not strictly speaking a paper review, or a 'professional' opinion (which I believe was the goal of posting this past week), but something I think would be interesting - a review of reviews - and make a nice conclusion for the past week. (And I haven't got round to reading another paper - man-'flu has struck once again...).

On Monday, a paper by Bechara et al. on the relationship between emotion and decision making was reviewed (the somatic marker hypothesis). The study essentially found evidence supporting the view that emotion is a central part of decision making, as it's use provides a filter-like function which reduces the decision space and enables decisions to be taken in a time-frame suitable for action in the real world. On Tuesday, a paper on brain based devices by Krichmar and Edelman was looked at. This paper provided an introduction to this work, presenting the principles of building devices (robots) according to neurobiological rather than computational principles. These principles have formed the basis of the Darwin series of robots which are capable of complex learning and completion of tasks - all of which are self learned without explicit pre-programming. Wednesday saw the review of a maze task often used in rat studies to assess spatial memory: The Morris Water Maze. As mentioned, this maze has also recently found use in robotics studies for a similar purpose, as it provides a challenge which involves the interaction of sensory and motor systems, as well as the requirement for memory - all of which are required for an autonomous agent. The posts for Thursday and Friday were somwhat shorter, with Thursday providing a brief discussion on why using artificial agents in the study of biological systems may be useful (something I hope to expand on in a future post), and Friday with a brief review of a paper by Sane et al on the presence of a gyroscope-like system in moths which enable them to achieve a steady flight in the absence of visual cues, which I use as a simple example of the importance of physical implementation of a system as well as the control system. Finally, yesterdays post provided a brief introduction to a tutorial on Humanoid Robotics by the Idaho National Laboratory, which I think is well worth a read.

So, if there is a theme to be found among these posts, it would be a review of work from a wide range of disciplines and their applications to cognitive robotics. I think two things can be said for this: firstly that if one wants to maintain the biological plausibility of a cognitive model, one must take into account the necessities and limitations of the biological system(s) of interest; and secondly, that expanding one's horizons and examining the work of others in different (sometimes completely different) disciplines can provide you ideas and inspiration which would be hard to come by in any other way. That's the hope of my work... hopefully... sometime in the future... :-s

Finally, I'd like to thank all the contributors to the Just Science Week for their interesting and informative posts, and I hope that next year will be just as good. Although I hope that then, I'll be able to keep up with the one-paper-review-a-day thing.

Filed under: blogging, links, Week of Science, Cognitive Robotics, Comment
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The February issue of Current Directions in Psychological Science points to several studies that indicate facial composite systems produce a poor likeness of the intended face. In one particular study, only 2.8 percent of participants correctly named a well-known celebrity that had been created by other participants using the face-composite software.

Dynamic face recognition may be one of the last frontiers for quantifying why some of our simplest brain functions have difficulty being matched by computers.

As a kid, when computers were more basic, it was easy to see the differences between my brain and the power of a computer. When I played baseball I knew the instant the ball was hit whether I had to run back or forward. This was a spectacular amount of mathematics done in an instant with the only programming being my amount of practice. A computer has to be able to define a parabola before it can tell me which way to run - by the time it could tell me where to run, the ball will have landed.

The only reason I bothered to show up for trigonometry was to figure out a methodology that could help me write a computer program to catch a baseball without having the computer know where the ball was going to be hit in advance.

Facial recognition today faces similar obstacles. If you look at your favorite scientist's irritated face while his supermodel storms out because he did not tell her she was beautiful for the requisite hundredth time that day, it looks a certain way. If he then looks happy because he finally got some peace and quiet, it looks another way. To you, it is easily the same person but a computer has a very difficult time with that operation.

A three-year old child can look at a real chicken and then a cartoon chicken and say, "That's a chicken." A computer has a difficult time with that also.

"Numerous lines of evidence converge on the view that faces are generally processed, stored and retrieved at a holistic level rather than at the level of individual facial features," said Gary Wells and Lisa Hasels of Iowa State University in the Current Directions in Psychological Science article.*

In the late 1970s research on this began to kick into gear, mostly because of vision applications. Scientists wanted to determine how much information was essential for visual recognition. Similar to hearing, we can determine frequencies of interest for vision. In this case, the frequencies are spatial and the research was done by AP Ginsburg.** He used bandpass filters to determine which spatial frequencies carried the most information and therefore could be isolated to make recognition easier. He narrowed down the important range of frequencies but, also important, he discovered that different spatial-frequency sets supplied the information for different perceptual and cognitive functions - like emotions, which would allow a computer to recognize a scientist whether he is happy or bothered.

It's only now that home computers will contain the horsepower to do this kind of number crunching. The field of identity recognition is easily covered today but emotional recognition - the kind of thing that allows a computer to recognize me regardless of my supermodel irritation level - still has some way to go.

I've tried to find some legitimate modern research that makes this big improvement but so far it just involves brute-force techniques and more computing power to identify and match grid-by-grid; hardly an elegant solution.

Yet while emotional variance recognition is still lacking, ordinary face recognition has grown tremendously. I went to a site called My Heritage and tried their tool. The demo version allows you to input your picture and tells you what celebrities you look like. Naturally, I had to give that a try. So I threw in my picture and it comes back with the four people in the graphic.

MyHeritage.com said I am a combination of Trent Rezner, Scott Bakula and Jackie Chan. I wasn't sure how that Colin Firth guy fit in there but I remembered he seduced Keira Knightley in some movie or another, so it makes sense now.

They think I am a rock star, a quantum physicist and the greatest martial arts action hero of all time? The authors of the recent article may not be convinced but I think this software is so accurate it is almost spooky.

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Sexual selection is an expansive topic. It is also one with a complicated history and fits messily into a rigorous empirical research program. I will base this post predominantly on the verbal exposition in R.A. Fisher's The Genetical Theory of Natural Selection. My reason is simple: though progress in formalization of sexual selection theory has been significant within the past 25 years, the major issues and concepts were sketched out by Fisher.

Prior to Fisher sexual selection was discussed quite extensively by Charles Darwin, but unlike natural selection it was roundly rejected. Both Thomas Huxley and Alfred Russel Wallace attacked it as implausible and inconsequential, and many contemporaries found the idea of female mate selection as a driver of evolutionary change ludicrous. Fisher's discussion of the topic in The Genetical Theory of Natural Selection was one of the few serious examinations of the topic before the contemporary period subsequent to Darwin. The whole sordid tale of the culturally rooted rejection of sexual selection theory is detailed in The Mating Mind, Geoffrey Miller's attempt to reinterpret human evolutionary history through the lens of this process.

There are multiple forms of sexual selection. First, one must distinguish between intrasexual selection, and intersexual selection. The former consists primarily of competition between males which results in differential access to, or superior utilization of, mating resources. A common example might be ritual combat which determines the extent of a male's territory, with that territory being proportional to the number of resident females whom the "owner" of the territory may have an opportunity to mate with. Another example of intrasexual selection is sperm competition, that is, differences in the nature of sperm (e.g., in motility or seminal viscosity) which results in different likelihoods of fertilization. Intersexual competition consists primarily of female mate choices which result in differential mating success across the males within the population. The main reason that females are the focus of intersexual selection is that in most species of interest they are the limiting sex in relation to natural increase, i.e., a small number of males can inseminate innumerable females. This does not mean that intersexual selection is exclusively female to male, and some have argued that humans are one of the primary exceptions to this rule of thumb, as in our species females are subject to mate choice as much as the inverse situation.

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Just Science Week has officially passed. Some what successfully. Before we return to our regular chatter, filling the internet with verbal debris, some related observations…

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Strange, but some might find amusing...



Link to the rest of the videos, their lyrics, and background info here.

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You can see from yesterday's post and comments that we are tapping into the science of fish baloney. A commenter took offense to my remarks and misspelling of surimi, a processed food product made from pollock. Pollock, hake, and cod are Gadiforms in the families Gadidae and Moridae. Together these fish feed millions of people. I apologize for any misgivings. I actually like surimi and bologna. Baloney and cheese sandwiches are my favorite snack to bring kayaking. Seriously. They stay fresh all day.

The commenter also pointed out that I need to do more research before I write about this stuff. This is undoubtedly true. I apologize again. My intention was to write about fishes. Yesterday was a meandering prologue that never quite reached the point. I wanted to say, "When you see frozen fish sticks, think cod; when you eyeball the seafood salad at Subway, think pollock." Deep-sea fishes are all around us, but we know very little about them. For example, did you know cod have a bioluminescent anus? And they cannibalize their young? If not, please, read on.

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Gene and DNA patents concern those who worry that important life-saving information will be locked away by those whose only desire is to make a profit. A recent study of over 15,000 patents involving DNA sequences has found that patents on DNA are no longer growing apace. Only one third of patents have been granted while the rest were had been denied, withdrawn, or stuck in the application process.

Dr Michael M Hopkins, Dr Surya Mahdi, Mr Pari Patel and Professor Sandy M Thomas at SPRU - Science and Technology Policy Research, at the University of Sussex, UK have concluded that a number of factors have made it more difficult to patent genes and DNA, including:

• New guidelines at patent offices
• Legal developments
• Commercial sentiment
• Availability of genetic information in the public domain
• Cost and difficulty of obtaining a patent, esp. in Europe

The US patent office has apparently granted many more gene patents than other countries in Europe and Japan.

Denise Caruso wrote about patents in the biotech industry last month for the New York Times. Here’s a reprint in the Tuscaloosa News.

Medical News Today, February 11, 2007
Photo: German Patent Office from genome4hire

Tags: genetics, genes, genome, dna, patents, biotech, diseases, illness, health

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from the AP wire: Significant inventors honored Thursday on Capitol Hill

WASHINGTON (AP) — Inventors of the MRI, the Ethernet, the LP record and a popular weedkiller are among 18 people picked for induction into the National Inventors Hall of Fame.

The 2007 class of inductees was to be announced at an event Thursday on Capitol Hill. The honorees are joining luminaries such as Thomas Edison, Velcro inventor George de Mestral and Charles Goodyear, developer of vulcanized rubber.

“Some of these inventors … have literally changed the way we live our lives,” said Rini Paiva, spokeswoman for the National Inventors Hall of Fame Foundation. But, she added, “they are not household names.”

Among the latest inductees and their inventions are:

—Paul C. Lauterbur, for the MRI, or magnetic resonance imaging.

—Robert M. Metcalfe, for high-speed networking known as Ethernet.

—the late Peter C. Goldmark, for the long-playing record.

—John E. Franz, for the herbicide Roundup.

The Akron, Ohio-based hall was founded by the U.S. Patent and Trademark Office and the National Council of Intellectual Property Law Associations. It has inducted members since 1973 and will have honored 331 inventors with the new class.

The ceremony will be in May. More information will be at the National Inventor Hall of Fame website at http://www.invent.org.

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We often think of invasive or noxious species as exotic species that have come to a new area from some far off place-examples include the starling, fire ants, zebra and quabba mussels, or kudzu. Indeed here in Eastern Kansas its difficult to find a habitat that doesn't have it's complement of these sorts of invasive species. Yet some native species have characteristics of invasive species. A good example in Kansas is the red cedar.

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Continuing with the theme of a Week of Science sponsored by Just Science, we will highlight some of the key points in: Appelhans BM, Luecken LJ. Heart Rate Variability as an Index of Regulated Emotional Responding. Review of General Psychology. 2006;10:229–240. Effective emotional regulation depends on being able to flexibly adjust your physiological response to a changing environment moment by moment.Heart rate variability (HRV) is a measure of the continuous interplay between sympathetic and parasympathetic influences on heart rate that yields information about autonomic flexibility and thereby represents the capacity for regulated emotional responding.

Filed under: Cognitive Neuroscience, Health & Wellness, Brain Fitness, Brain health, health & wellness, Mental flexibility, Decision making, Emotions, Executive Functions, Freeze Framer, Stress, Neuropsychology, attention
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Wherever the abilities involved are sufficiently distinct--and that is in the great majority of cases--our tetrad equation is satisfied with surprising exactitude, so that here each ability must be divisible into g and s. The letter g becomes, in this manner, a name for the factor--whatever it may be--that is common to mental tests of such a description. This is the very definition of g. (Spearman, 2005, p. 161)

General intelligence (g) has been one of the most, if not the most, aggressively studied constructs in psychology. Type the search string "general intelligence" in PsycInfo and you will return over 2000 entries, and a similar search in Pubmed pulls up over 400. If you broaden the term to just "intelligence", the respective number of entries are 65405 and 37166. While not all of the results focus on g , (e.g., AI, "social intelligence"), a large portion of them do, and the prospect of meandering your way through can be intimidating. Fortunately, the overall literature is consistent and, at least for me, highly engaging.

The study of g can be bifurcated into two distinct areas: vertical and horizontal g . Vertical g is the domain that studies g's biological relationships. It is the area that is going to eventually assimilate enough data and literature to elucidate, unquestionably, the causal mechanisms of g . From this field of study, we know that g is correlated with a variety of neural mechanisms, such at glucose metabolism (Haier, 2003), cortical development (Shaw et al., 2006), and biochemical activity (Jung et al., 2005). We know that g is highly heritable, both when measured psychometrically (Plomin & Spinath, 2002) or chronometrically (Beaujean, 2005). We know that g decreases with inbreeding (Jensen, 1983) and increases with hybrid vigor (Nagoshi & Johnson, 1986). As genome scanning becomingmore popular, we are now even beginning to see some specific genes that are implicated g.

As interesting as vertical g is, however, this entry is going to instead focus in the horizontal aspects of g . That is, how does g play out into "everyday life." Specifically, we will look three different, although related, areas: education, occupation, and general life outcomes. The reasons for doing so are twofold: (a) the more the science of horizontal g is positively promulgated, then, perhaps, the more likely people are to support the needed research into vertical g and (b) even though this area of research has been around for over a century (e.g., Galton, 1869), there are still new, important findings.

Before delving into horizontal g, however, it would behoove us to delineate a mechanism by which g could influence education, occupation, and general life outcomes.For our purposes, that mechanism is information processing. Generally defined, information processing is the pathway and mechanisms by which stimuli are perceived, attended to, retrieved, and/or used to solve problems and/or cope with exigencies in the environment (Jensen, 1998a). The cognitive psychology literature is chalked full of the nuances of the various information-processing theorists, the specifics are which cannot be delineated here (an easy-to-read intro: Ormrod, 2004). Yet, within all these theories lies the idea that people respond to stimuli in a way that involves many mechanisms (e.g., sensory register, primary memory)and a variety of neurological regions (e.g., hippocampus, amygdala, mammillary bodies). The consequence? There is ample room for individual differences in the speed and efficiency in which information is processed.

From another perspective (e.g., Kline, 1998), information is processed in irreducibly small pieces (often called bits) and the time it takes to process those bits is the BIP, the Basic period of Information Processing. Now, the time it takes Johnny to process the fact that the only integer between 2 and 4 is 3 is going to be different than the time it takes Jane. Multiply those differences by the number of people processing the fact, and voila! individual differences.

Educational Outcomes

This is probably the area most replete with data and, unsurprisingly, the g-educational achievement relationship is strong. In fact, although it differs by grade level (with it decreasing as grade level increases), most of the non-random variance in scholastic performance is accounted for by g (Thorndike, 1984). Jensen (1989, 1998b) writes that this is so due to the fact that "school learning" is, itself, quite g -loaded. Of course, there are those who write that g is just a product of education (e.g., (Ceci, 1991); for a review of others, see Gottfredson, 1986), or, perhaps more egregious, that g and educational achievement are just products of the tests designed to measure them (for review and rebuttal, see Jensen, 1984). But these arguments quickly dissipate when looking at the evidence.

For example, in the latest issue of Intelligence, there were two longitudinal studies (Deary, Strand, Smith, & Fernandes, n.d.; Watkins, Lei, & Canivez, n.d.) that showed a strong IQ --> Educational Achievement relationship (approx. 70 from Deary), but reverse (i.e., EA --> IQ) was not there (from the Watkins study). Further evidence comes from the two major "We can improve you Education by improving your IQ" projects: Head Start and the Abecedarian Study. With regard to the former, Head Start just does not produce long-term IQ gains and, hence, does not produce long-term academic gains (Caruso, Taylor, & Detterman, 1982; Holden, 1990, March 23; Kreisman, 2003). With regard to the latter, while there has been acrimonious debate, the overall conclusion is that, like Head Start, the initial IQ gains do not last, givning even more evidence that educational achievement cannot be raised independently of g (Spitz, 1986, 1992, 1993b, 1993a).

Yet another line for arguing against the prominence of g in education is the idea that there are other traits that are just as necessary for academic success, such as motivation, personality, etc. To risk sounding like to broken record, the data shows that these traits are not nearly as potent predictors as g in predicting academic outcomes. For example, Gagne and St. Pere (2002) gives us reason to believe that motivation might just be an impotent variable in predicting academic achievement.Likewise, Laidra, Pullmann, and Allik (2007) has shown that while personality factors contribute some to the variance in educational achievement, they are dwarfed in comparison to the contribution of g.

Occupational Outcomes


There are many theories as to how g and occupational outcomes relate (see Gottfredson, 1986), but the one that is most supported by data is best explicated by Frank Schmidt and John Hunter

[g] predicts both the occupational level attained by individual and their performance within their chosen occupation. [g] correlates above .50 with later occupational level, performance in job training programs, and performance on the job. Relationships this large are rare in psychological literature and are considered "large" . . . weighted combinations of specific aptitudes (e.g., verbal, spatial, or quantitative aptitude) tailored to individual jobs do not predict job performance better that [g ]measures alone, thus disconfirming the specific aptitude theory. It has been proposed that job experience is a better predictor of job performance than [g ], but the research findings . . . support the opposite conclusion. . . . Nearly 100 years ago Spearman (1904) proposed that the construct of [g ]is central to human affairs. The research . . . supports his proposal in the world of work, an area of life critical to individuals, organizations, and the economy as a whole.(Schmidt & Hunter, 2004, p.171; cf.Schmidt & Hunter, 1998)

One could argue that, given the high g -education relationship, that the g-occupation relationship is just a natural outgrowth.That is, once education is controlled, the g-occupation relationship significantly shrinks (i.e., mediation). But to make that argument, one would have to have a Sternberg-like approach to intelligence (Sternberg & Wagner, 1993).That is, that the cognitive skills involved in a successful education are somehow vastly different than those needed for everyday life. The data, however, indicate that the same generative process that tends to makes one successful in the educational arena is also the mechanism that tends to make one successful in the occupational arena: g (Kuncel, Hezlett, & Ones, 2004). This is not to say that other things are not important in occupational or educational outcomes; but, as with education, they are not nearly as potent predictors (Gottfredson, 2002).

Life Outcomes

Over the last decade or so, an area that has become of more interest to the intelligence community is the influence of g on general life outcomes. That is, beyond educational and occupational outcomes, does g contribute to life success? The answer here, too, seems to be a resounding yes.

IQ scores [a proxy for g] predict a wider range of important social outcomes and they correlate with more personal attributes than perhaps any other psychological trait. The ubiquity and often-considerable size of g's correlations across life's various domains suggest g truly is important in negotiating the corridors of daily life. (Gottfredson, 2003, p. 326)

But how does g relate to general life outcomes? Believe it or not, it appears that the same information-processing mechanisms that are so potent for educational and occupational outcomes also play a role in day-to-day life (Gottfredson & Deary, 2004). Gottfredson (2003, 2004b) elaborates this mechanisms as follows: Life is is made up of many tasks with a wide array of complexity (Gordon, 1997). In the US and most Western nations, society is "free enough" for competence (read: g ) to make a substantial difference in who succeeds in life. As those who have "higher g" are more able to tackle the day-to-day activities of life successfully with less exerted effort, they are able to progress in life with fewer impediments (e.g., untreated illness, accidents Gottfredson, 2004a), thus allowing them to (a) have more resources to successfully compete and (b) be able to u