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Journal Journal: Shot Show coverage 2

I flew down to Las Vegas to do some work that I'll talk about here later. But while I was in town, I took two days to document Media Day and Shot Show 2010 for a number of sources including Wired, The Firearm Blog and other resources. There was some interesting new technology including a new pistol from Armatix that uses RF signals to disable the sidearm if it is too far from the wristwatch the accompanies it. Also new ballistics computers that are mounted on rifles are discussed.

New JonesBlog update(s). Shot Show 2010 Media Day

Shot Show 2010. The Actual Shot Show

and a little after party. AAC Big Bang Party

The Matrix

Journal Journal: Bionic implants 10

New JonesBlog update. Bionic implants

The device seen in these images is called the Utah Electrode Array (WARNING: potentially graphic image after the jump of an implant in a human brain). The Utah Electrode Array is a brain implant technology developed here at the University of Utah by Richard Normann. The purpose of this device, built by currently built for us by Blackrock Microsystems is to transduce signals from external devices to deliver to the brain for interpretation. Alternatively, the device can record impulses generated in the brain for delivery of neural signals to external devices. Our potential interests in this approach are manifold, but real use and implementation of these devices is some years away still.

User Journal

Journal Journal: 1-3% of all mainstream stars have planets?

The venerable BBC is reporting that a survey of light emitted from white dwarfs showed that between 1% and 3% had material (such as silicon) falling into the star on a continuous basis, potential evidence of dead worlds and asteroids. On this basis, the authors of the study speculate that the same percentage of mainstream stars in the active part of their life will have rocky matter. This is not firm evidence of actual planetary formation, as asteroids would produce the same results, but it does give an upper bound and some idea of what a lower bound might be for planetary formation.

Aside from being a useful value for Drake's Equation, the rate of planetary formation would be valuable in understanding how solar systems develop and what sort of preconditions are required for an accretion disk of suitable material to form.

Because the test only looked for elements too heavy to have been formed in the star, we can rule out the observations being that of cometary debris.

User Journal

Journal Journal: Computational Framework for Mapping of Neural Circuitry 15

New JonesBlog update. A Computational Framework for Ultrastructural Mapping of Neural Circuitry

We have just published a manuscript in PLoS Biology where we describe how to build a complete and accurate neural network. This of course is one of the long standing holy grails in neuroscience. So, this effort meets two goals: 1) It meets the goals of building a complete neural connectome (we'll be finished collecting all of the data with cell identity, physiologic response and all synaptic connectivity in approximately six days) and 2) It defines a workflow whereby investigators from around the planet can download and use the tools we are providing to build their own connectome projects using existing infrastructure. We are making those tools available here to enable other groups to assemble, browse and annotate the terabyte sized datasets required of connectome level projects.

User Journal

Journal Journal: Fireball, but not XL5 3

Four fireballs, glowing blue and orange, were visible last night over the skies of the Carolinas on the southeast coast of the United States, followed by the sound of an explosion described as being like thunder. Reports of hearing the noise were coming in from as far afield as Connecticut. There is currently no word from NASA or the USAF as to what it could be, but it seems improbable that anything non-nuclear the military could put up could be heard over that kind of distance. It therefore seems likely to be a very big meteorite.

The next question would be what type of meteorite. This is not an idle question. The one slamming into the Sudan recently was (a) extremely big at an estimated 80 tonnes, and (b) from the extremely rare F-class of asteroid. If this new meteorite is also from an F-class asteroid, then it is likely associated with the one that hit Sudan. This is important as it means we might want to be looking very closely for other fragments yet to hit.

The colours are interesting and allow us to limit what the composition could have been and therefore where it came from. We can deduce this because anything slamming through the atmosphere is basically undergoing a giant version of your basic chemistry "flame test" for substance identification. We simply need to look up what metals produce blue, and in so doing we see that cadmium does produce a blue/violet colour, with copper producing more of a blue/green.

Other metals also produce a blue glow and tables of these colours abound, but some are more likely in meteoric material than others. Cadmium exists in meteorites. Well, all elements do, if you find enough meteorites. but it exists in sufficient quantity that it could produce this sort of effect. (As noted in the chemmaster link, low concentrations can't be detected by this method, however this is going to be vastly worsened by the fact that this isn't a bunsen burner being used and the distance over which you're observing is extreme.)

Ok, what else do we know? The fireballs were also orange. Urelites, such as the Sudan impact, contain a great deal of calcium, which burns brick-red, not orange. This suggests we can rule out the same source, which in turn means we probably don't have to worry about being strafed the way Jupiter was with the Shoemaker-Levy comet (21 impacts).

What can we say about it, though? Well, provided the surviving fragments didn't fall into the ocean, it means every meteorite hunter on the planet will be scouring newspaper stories that might indicate where impacts occurred. Meteoric material is valuable and anything on a scale big enough to be heard across the entire east coast of the US is going to be worth looking for. It had split into four in the upper atmosphere, so you're probably looking at a few thousand fragments reaching ground level that would exceed a year's average pay.

User Journal

Journal Journal: Korean DMZ 4

New JonesBlog entry on a visit to the Korean DMZ here.

This is a glimpse at an environment that hopefully will be rapidly changing, but with North Korea going through a spasm of Communist retrenching and the uncertainty of Kim Jong Il's health (or even if he is still alive), things in the DMZ appear to be just as tense as they have been for years.

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