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Happy Towel Day 122

An anonymous reader writes "While Douglas Adams continues his attempt to set a new record for the longest extended lunch break, geeks all over the universe pay tribute to the beloved author by celebrating the tenth edition of Towel Day. Towel Day is more alive than ever. This year Richard Dawkins, one of Adams' best friends, has tweeted a Towel Day reminder to his numerous followers. The CERN Bulletin has published an article on Towel Day. There has been TV coverage and there will be a radio interview. The Military Republic of the Deltan Imperium, a newly formed micronation, has recognized Towel Day as an official holiday. In Hungary several hundreds of hitchhiker fans want to have a picnic together in a park. And there's a concert, a free downloadable nerdrap album, a free game being released, the list goes on and on."

Mars Images Reveal Evidence of Ancient Lakes 128

Matt_dk writes "Spectacular satellite images suggest that Mars was warm enough to sustain lakes three billion years ago, a period that was previously thought to be too cold and arid to sustain water on the surface, according to research published today in the journal Geology. Earlier research had suggested that Mars had a warm and wet early history but that between 4 billion and 3.8 billion years ago, before the Hesperian Epoch, the planet lost most of its atmosphere and became cold and dry. In the new study, the researchers analysed detailed images from NASA’s Mars Reconnaissance Orbiter, which is currently circling the red planet, and concluded that there were later episodes where Mars experienced warm and wet periods."

Scientists Say a Dirty Child Is a Healthy Child 331

Researchers from the School of Medicine at the University of California have shown that the more germs a child is exposed to, the better their immune system in later life. Their study found that keeping a child's skin too clean impaired the skin's ability to heal itself. From the article: "'These germs are actually good for us,' said Professor Richard Gallo, who led the research. Common bacterial species, known as staphylococci, which can cause inflammation when under the skin, are 'good bacteria' when on the surface, where they can reduce inflammation."

Revisiting the Original Reviews of Windows Vista 414

harrymcc writes 'We now know that a remarkable percentage of consumers and businesses decided to spurn Windows Vista and stay with XP. But did the reviews of Vista serve as an early warning that it had major problems? I looked back at the evaluations in nine major publications and found that they expressed some caution--but on the whole, they were far from scathing. Some were downright enthusiastic.'

Comment Re:spoooooky (Score 3, Informative) 287

It detects the oxygenation of blood. The mechanism behind this is a different magnetic moment of oxygenated hemoglobin, oxygenated hemoglobin is diamagnetic vs paramagnetic while deoxygenated. This is called the BOLD effect (Blood Oxygen Level Dependent). The difference in the two conditions magnetic property affects the MRI signal lifetime in the near vicinity. This results in contrast developing between tissues with oxygenated blood vs tissue with deoxygenated blood. The idea behind fMRI is that when you use a certain part of the brain, it requires oxygenated blood, which will lead to contrast. Unfortunately, due to low overall signal strength/contrast-to-noise ratio, the image must be signal averaged. Hence if you were tapping your finger to see which part of your brain "lights up", you would have to repeat this action, and have your MRI scan be synced to your action so that the same part of the brian is being imaged over the same interval each time. It's tricky, but my understanding is that it's quite feasible. There are many other mechanisms for causing localized signal lifetime changes, without having RTFA, I can't be sure what they took under consideration.

Comment Re:Different everywhere? (Score 1) 451

I am a Colombian-American, Caleño to be exact. Bogotà is very temperate, whereas Cali is very very tropical: hot and humid most of the year. But the escape to the mountains is still the same, just oh so much more dramatic. I prefer *up* the hill, I can't take 80s and 90s with humidity all the time. So sticky... but the nights are wonderful. Up the hill gets a bit chilly... some panela will take care of that, perhaps sancochito... or in your case, ajiaco.

Comment How this works (Score 4, Informative) 237

Disclaimer: I'm an MR Physicist.

Regarding gradients: The gradients used in MRI vary in *position*. Yes in time, as well, but only because they are pulsed. We can ignore ramping issues to first order. Since the field varies as a function of position, when you move around, indeed the flux is changing which can induce currents in looped conductors so as to oppose the change. This is called induction. Many people, my self included, notice a strange sensation when first entering an MRI magnet. This is because the field is only homogeneous over a relatively small volume, outside of which there are once again field gradients (these are different than the intentional field gradients used to obtain an MRI image). It is probably not axons but something in the ear that is picking this up, I am not sure. Also, field strength has *nothing* to do with this effect. It's how fast the field changes as a function of position, i.e. the gradient, combined with the velocity of the pickup object.

Regarding repulsion: Water is diamagnetic. That means that the little spins (i.e. electrons) orbiting the atoms of a water molecule tend to align *against* the applied field direction. These spins will experience a repulsive force, hence the levitation.

Comment Build a clock radio! (Score 1) 364

Have them build a clock radio, with alarm. Lots of digital logic, cheap. A breadboard is useful so as to avoid soldering, and some kits to go with the breadboard (little wire segments). If you make them run it off of wall current, they'll have to learn how to go from AC to DC. Might take a few months of working in groups to do, but you can learn a lot that way.

Comment Re:LaTeX (Score 1) 338

I LOVE inkscape. That coupled with GIMP enables just about any graphic manipulation you want. Plus, inkscape has some plugins that allow you directly enter (and in one case edit) LaTeX code. All for free. Unbelievably useful. I have futzed with LyX, but because I am used to handcoding my tags, I doubt I will start using it. I use WinEdt to create my documents, though IMO the autotabbing leaves something to be desired.

Comment I'm skeptical (Score 1) 333

This should have appeared as a preprint on the xxx archives first, if it wants to be taken seriously. I see a bunch of math, and a disjointed argument. That sounds alarm bells in my head. I would not really pay close attention to this article until it was cleaned up and resubmitted and/or I heard the author present his ideas live, with the ability to ask questions and get clarifications.

Looking at Intel's New-ish Desktop Socket, LGA 1366 100

Slatterz writes "LGA 1366 is Intel's first new desktop socket in four years. It uses the same ZIF design as the familiar LGA 775 architecture, but it incorporates many more contacts. These big architectural changes are backed up by some less visible advances. Until now, Intel's quad-core processors have been constructed from two dual-core dies, but now Core i7 brings together four cores on a single die. It's also Intel's first processor design to use an L3 cache, shared between all four cores."

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